using the charts,calculators and basic math


Staff member
theres a hundred threads on this site answering various questions about how to properly select or installation of various components and its rather obvious that the most common questions are some variation on how to either build a decent running performance engine at low cost or trouble shoot various issues with engines that are already built.the key is and always has been to carefully match the components being selected to provide and slightly exceed the expected required and carefully calculated, air flow, rpm range and expected stress levels so you can make and maintain the power expected with a margin for extended durability,so you overcome the inevitable minor air flow and friction losses.
its rather obvious most guys would rather be boiled alive than read what they see as near endless links or sub links but you might be amazed at what youll learn, I know I WAS AS I DID YEARS OF RESEARCH, and RESEARCHED HOW to do things correctly ....yes usually after finding out how NOT to do things, or spending far too much money, like most guys!.

it should be rather obvious that after 60-80 plus years since Chevy,Pontiac,Buick,Olds, Plymouth ,Ford and mopar first produced a v8 engines that a great deal of research and engineering time has gone into building and modifying those engines and that the more popular of those engines that have longer production runs lasting decades like the Chevy,Pontiac, and many Ford and mopar engine have had significant research done and parts produced. thus a bit of research into what HAS worked and what HAS BEEN successful and what has been shown to be the most successful trends should lead anyone whos willing to do some research to several previously successful combos that can be copied, or at least closely duplicated once the basic operational details are understood and logically one should understand the basics of why the basic components function like they do, and what previous combos or modifications failed miserably, as well as what succeeded , so previous mistakes can be avoided.

I was asked several dozen times for a good basic combo that won,t break the bank that would result in a nice street engine based on your basic first generation sbc, keep in mind low cost is relative and low cost and quality and long term durability may not be compatible, so I,m talking about a total fresh rebuilt where you have a good rebuild-able 350 block, and decide to build a fresh 383, that will produce over 430 hp at the fly wheel and should last 100K miles or more,ALL THE FACTORS REQUIRED IN THE BUILD CAN BE CALCULATED and it will be designed for street use where it will spend the vast majority of its life at under 4000rpm, and rarely see north of 6300rpm, so low speed torque is important just as upper peak power, so it should push you back in the seat easily if you floor the throttle but not be a problem if you want to drive across the country (well gas mileage will not be great) and compromises were made, but theres a big difference between building a performance engine you might reasonably expect to go 100K miles with minimal maintenance, and an all out race engine that will be rebuilt after each race or at least at the close of the season, that would be expected to spin 7000rpm and not be expected to perform below 4500rpm.

well, to start with a low cost build and I mean to minimize the cost every place I reasonably can, Id strongly suggest we keep cost to a minimum and start with a basic 350 first gen block thats no more than .030 over bore as the stock blocks are not all that rigid, Id maximize the blocks displacement with a SCAT CAST STEEL CRANK, BASED ROTATING ASSEMBLY, YES YOU WANT THE 7/16" CONNECTING ROD UPGRADE as its significantly stronger, 5.7" or 6" your choice ID prefer the 6" rods myself but either will work.
forged pistons are preferred but hyper-eutectic pistons will work ok if you keep the engine rpms reasonable (with a mild performance 383 thats generally about 6200rpm max) and the engine out of detonation.
Id select and edelbrock air gap intake and a 600cfm-700cfm vacuum secondary carb
on a street car Id prefer a manual transmission, and at least 3.35:1 rear gears but 3.73:1 are ideal
ID want about 9.5:1-10.5:1 static compression to maximize torque but obviously youll need to carefully select the cam timing to get a dynamic compression near 8:1 to run pump octane fuel and aluminum heads that flow at least 250 cfm at .0500 lift,to flow enough air to adequately fill a 383 cylinder at 6300rpm. and Id select a solid lifter flat tappet cam, or if forced into it a hydraulic flat tappet cam, with at least a .500 lift and a 235-245 dur. at .050 lift cam to maximize performance per dollar are about mandatory for maximizing performance , roller cams are great but they are expensive.
Id damn sure put the time in to find a decent 7-8 quart baffled oil pan with a effective windage screen,that fit the car because maintaining consistent oil pressure is mandatory for durability
heres a calculator to calculate ideal port cross sectional area
on a street driven 383 Id design the build to put that some place in the 4000rpm-4500rpm band
youll generally dump 30%-40% of your budget into good cylinder heads because they hold the key to much of the engines performance potential, on a 383, youll want a 195-215cc port size , if your intent on max power Id go with a larger port cross sectional area, a smaller port will restrict upper rpm power but result in more mid rpm torque ,your choices depending, mostly on gearing, and cam selection and intended operational rpm band.
now keep in mind this is NOT intended to be a max performance build , and you could rather obviously boost peak power with a with more compression, larger port heads, a well designed single plane intake and a larger carburetor and perhaps a wet nitrous plate, and a serious roller cam, but that would also add significantly to the engines cost and tend to make it far less likely to be useful for daily transportation.
a very common misconception, "that the intake runner size has the most effect on the engines torque curve,is mostly a myth" in reality ,compression ratio, cam timing and engine displacement and proper exhaust scavenging ALL have a larger effect on the engines torque that the intake runner cross sectional area.(yes getting it correct helps but your more likely to cause a problem by selecting an intake port and runner combo thats too small and restrictive than one thats too large in cross sectional area.





















torque curve closely matches the cylinder fill efficiency ,

felpro # 1204=Port Size: 1.23" x 1.99"=2.448 sq inches

felpro # 1205=Port Size: 1.28" x 2.09"=2.67 sq inches

felpro # 1206=Port Size: 1.34" x 2.21"=2.96 sq inches

felpro # 1207=Port Size: 1.38" x 2.28"=3.146 sq inches

felpro # 1209=Port Size: 1.38" x 2.38"=3.28 sq inches

felpro # 1255 VORTEC=Port Size: 1.08" x 2.16"-2.33 sq inches

felpro # 1263=Port Size: 1.31" x 2.02"=2.65 sq inches

felpro # 1266=Port Size: 1.34" x 2.21"=2.96 sq inches

felpro # 1284 LT1=Port Size: 1.25 x 2.04''=2.55 sq inches

felpro # 1289 FASTBURN=Port Size: 1.30" x 2.31" 3.00 sq inches
valve seat and back face angles ,valve diameter and valve lift and duration effect the flow thru the curtain area

keep in mind that valve may be forced off its seat, too full lift and re-seating 50 plus TIMES A SECOND at near 5500 rpm, so theres very little TIME for gases to move through the very restrictive space between the valve seat and valve edge

Calculating the valve curtain area
The following equation mathematically defines the available flow area for any given valve diameter and lift value:
Area = valve diameter x 0.98 x 3.14 x valve lift
Where 3.14 = pi (π)
For a typical 2.02-inch intake valve at .500-inch lift, it calculates as follows:
Area = 2.02 x 0.98 x 3.14 x 0.500 = 3.107 square inches



there are quite useful ,cam selection soft ware programs that get you in the ball park, but the final selection is based on far more factors than most of those software programs address


if you read thru the links theres a ton of detailed info, but the charts and calculators in the links and sub links will all tend to guide you to a similar conclusion, a semi mild 383SBC can use a cam with about a 235-245 duration at .050 lift with about a 108-110 LSA and ideally about 520- 530 lift so youll generally run 1.6:1 roller rocker to get the required lift at the valve, with a flat tappet cam, obviously if you have the cash exceeding that lift but keeping the duration tends to result in more power potential but it costs more., do the required calculations so the cam you select and the engines compression ration allows you to get to about that 8:1 dynamic compression, and discuss the cam selection with the cam manufacturer.
Id also point out that the closer you are geared to that base 3.336:1 range the lower the cam duration should be, and the closer you get to lets say 3.73:1 the closer you can get to the 245 duration end of the cam range, while all the cams in the range will work, its best to maximize power where the gearing maximizes your average rpm band at cruising speeds

you can use calculators to figure out the best header config, but generally youll find its a 1.75" primary about 38-39" long with a 3" diam, 18"-20" long collector

it should be rather obvious that youll need to know the exact distance the piston deck sits at TDC ,above or below the block deck surface and the valve notch recess or pop-up dome volume of the piston to do accurate quench or compression calculations
floridas hardly the ideal climate for keeping tools rust free so i generally take my set of micrometers out of the storage case and open and close them and spray them down with a light oil like WD 40 and place them back in the box then place the whole box in a 2 gallon zip lock bag in a shallow tupper ware type air tight storage box that is just the size to fit inside one of your tool chest drawers too protect the precision measuring tools , feeler gauges and plasti-gauge youll need to measure clearances correctly.when not in use along with the dial calipers.


the reason I bring this up is I recently was over at a friends house where I needed to accurately measure a u-joint bearing cap and asked if he had a micrometer or dial caliper, he responded he had a very expensive looking imported micrometer, he had acquired recently at an estate yard sale for $30,

when he opened the very impressive looking brass and mahogany box the micrometer, inside was a solid rusted mass, I soaked it in marvel mystery oil and acetone mix for 30 minutes then gradually worked it loose and polished it up with 1500 grit wet/dry sand paper figuring no loss at this point and was amazed that after about 30 minutes of constant cleaning it not only looked fairly decent it seemed to read accurately on a test gauge so I think it was mostly ugly surface rust, but it sure looked horrible, and to someone who appreciates good tools,that was depressing.

btw look around at yard sales and estate sales every so often youll find amazing bargains in used precision tools
yes it sure helps to have the correct tools and know where to measure parts






heres a chart FROM THE BOOK,HOW TO BUILD BIG-INCH CHEVY SMALL BLOCKS with some common cross sectional port sizes
(measured at the smallest part of the ports)
...........................sq inches........port cc
edelbrock performer rpm ....1.43.............170
afr 180.....................1.93.............180
afr 195.....................1.98.............195
afr 210.....................2.05.............210
dart pro 200................2.06.............200
dart pro 215................2.14.............215
brodix track 1 .............2.30.............221
dart pro 1 230..............2.40.............230
edelbrock 23 high port .....2.53.............238
edelbrock 18 deg............2.71.............266
tfs 18 deg..................2.80.............250

related info

















theres lots of charts in the links like this one that provide info, if you have a 383 thats about 48 cubic inches per cylinder, divided by intake valve diam. we get 23.7, looking at the chart we see a LSA of about 106 should be the most efficient

the chart above can be used as a rough guide to match cam duration at .050 lift and static compression in engines obviously other factors come into play so its only a rough guide, when you use a cam with significantly more duration than suggested drive-ability and lower rpm power can suffer

4000 feet per minute in piston speed is generally considered a safe make on a mild performance build with upgraded components, a 383 with its 3.75" stroke would see that as about 6400rpm,but hydraulic lifters tend to float a bit lower so call it 6200rpm, look at the chart and we see a engine with the 383 roughly 48 cubic inch per cylinder needs a 230-240 duration to match that power band
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Staff member
as an example lets take this advice,if you want to build an old school 383-406 first gen SBC, on a reasonable budget for the power level reached, IT WON,T BE DIRT CHEAP BUT IT WILL BE A REASONABLY GOOD VALUE, youll generally be expecting too dump 30%-40% of your budget into good cylinder heads because they hold the key to much of the engines performance potential, an engine similar to this should easily produce respectable results in a fairly light weight car with a manual transmission as described
before you reach for your wallet, do some basic math and read a few dozen related links
USE THE CALCULATORS to match port size to intended rpm levels... but keep in mind valve lift and port flow limitations ... ch_engine/
and we will select a crower 00226 hydraulic flat tappet cam (because I know most of you guys hate lashing solid lifters) ... -7067.html
Lobe center 108
Advertised Duration: Intake / Exhaust 290 / 298
Duration @ .050" Lift: Intake / Exhaust 242 / 250
Rocker Ratio: Intake / Exhaust 1.5 / 1.5
Gross Valve Lift: Intake / Exhaust .507 / .522
crower FLAT TAPPET SOLID LIFTER 00304 ... -core.html
Duration @ .050" Lift: Intake / Exhaust 236 / 244
Gross Valve Lift: Intake / Exhaust .522 / .510
a CRANE 114681 if you want to go, a bit hotter with a solid lifter combo

ID go with 1.6:1 roller rockers to maximize lift. Ive used ERSON extreme duty, 1.6:1 SBC 3/8 stud rockers on at least 10 engines now with good results ... 9c&vxp=mtr

SCAT INTERNAL BALANCE 6" ROD 383 rotating assembly with 9.8:2 forged pistons $1160 ... oreDetails

you have several options on cylinder heads
brodix 200cc IK heads $1,308.33


edelbrock air gap intake $227 ... ProductId=

demon 625 cfm carb $330 ... ProductId=

youll obviously want a decent 7-8 quart baffled oil pan and a Z28 style oil pump to fit the chassis you select, because consistent pressurized oil flow protects the bearings and does most of the internal parts cooling and wear protection

obviously the components selected , how well they complement each other and the care taken during assembly maters but heres what DD2000 predicts for a similar flywheel hp result, but if you read thru the links and sub linked info and understand the concepts youll have a very good chance of avoiding many common mistakes and building an impressive performance engine.
keep in mind the combo above is for an old style muscle car engine with a manual transmission and a carburetor, the links below have more info if your building a TPI combo





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Staff member
Now Im reasonably sure this may not be what any of the newer guys in this hobby want to hear, but,unless you sit back and think things thru,and make a logical assessment of your skills, budget, and goals,your tools and where you have too work, your doomed to spending far too much time and money to get decent results by making many COMMON mistakes, keep in mind your hardly the first guy to want to build a killer combo on a limited budget with out a full understanding of how to correctly match components ... WELL WE ALL..... ALL STARTED THAT WAY , but the smarter guys, in any group learn from other guys mistakes , and try too avoid making as many as they can themselves. .... so avoid making as many mistakes as you can by understanding the basic concepts ,please under stand I,m trying to help and save you a great deal of time and wasted cash, you need to do some research before throwing cash at the potential engine build problem,youll need a better understanding of what factors like duration, lift LSA, and port flow rates compression ratio, etc. have on engine performance. what basic suitability of a cam design has on how it will effect the car or trucks engine and how gear ratio compression ratio and displacement and converter stall speed all must be matched to the application to build the engine correctly, yeah you can ignore this advise and think I'm F.O.S. here but in the long term youll see I'm trying to help , simply slowing down and doing a week or two of serious research into whats required,and the cost involved and having a realistic assessment of what you can afford to do, and have the skill too accomplish will save you a ton of cash and months of wasted effort.
even a basic calculator like this is very useful, so I carry one much of the time



start by buying these books and watching the video

you really should get these books and read them before going any further, it will help a good deal













bbcbl9.jpg ... ine-block/

start by buying these books and watching the video


JOHN LINGENFELTER on modifying small-block chevy engines



READ THRU THESE LINKS, AND SUB LINKED INFO.....yes it will take some time, but it will save your thousands of dollars and weeks of work and give you a good basic back ground knowledge
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Staff member
theres hundreds of related threads about various components , but it not simply the components you select alone, but the requirement to carefully match and fit components, correctly, theres a huge differences between bolting parts together out of the box and taking the time and effort to correctly clearance and fit components to reduce flow restrictions, increase oil flow rates reduce heat and part wear rates stress and fatigue.
some excellent info well worth reading thru
spending a few days or even weeks doing careful research well before you start writing checks or pulling out a credit card, can save you thousands of dollars and months of work, understanding the difference in component quality ,correct clearances and how and why each component is supposed to perform and the potential stress its under helps you make far more intellegent choices and tends to allow you to get an engine built that far exceeds the quality and performance of the average crate engine assembly
Engine Size
Exhaust Diameter

Single Exhaust
Dual Exhaust

150-200 CID 100 to 150 2″ to 2-1/4″ 2″
200-250 CID 100 to 200 2-1/4″ to 2-1/2″ 2″ to 2-1/4″
250-300 CID 150 to 250 2-1/2″ to 3″ 2″ to 2-1/2″
300-350 CID 200 to 350 2-1/2″ to 3″ 2-1/4″ to 2-1/2″
350-400 CID 250 to 550 3″ to 4″ 2-1/2″ to 3″
you might have somehow gotten the IN-CORRECT idea that the valve center-line and CYLINDER center-line are exactly matched in a sbc, they are NOT!
plus the valves are angled at a 23 degree angle so the outer valve edges close to the cylinder walls do not drop strait down into the bore as the valves open at the point of the cylinders largest diam. moving the head center-line to move the valve center- line to maximize flow at max valve lift potentially helps performance.
vgd4.jpg ... ch_engine/ ... d-porting/ ... 0Time!.pdf ... rt-Volumes

viewtopic.php?f=52&t=8460&p=29682&hilit=curtain+flow+angle#p29682 ... _Big_Block ... view&id=48


viewtopic.php?f=50&t=3422 ... index.html

valve seat and back face angles ,valve diameter and valve lift and duration effect the flow thru the curtain area


restrictive, as cast

less restrictive after unshrouding the valve


heres some old fuelie heads with the chamber slightly un-shrouding the intake valve pocket walls
polishing the combustion chambers and smoothing contours tends to reduce detonation and improve power, combine that with port and bowl area clean-up and careful blending of the port walls. and a back cut on valves with a multi angle valve job, etc. and its not unusually to gain 25-40 hp or more, from port work and combustion chamber mods that improve air flow rates







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solid fixture here in the forum
since you are talking a bit about porting and the like i thought this would be a good place to post this.... dont think that because you bought an aftermarket intake that there isnt room for impovement!


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    Fairlane_Magazine_Article_2 5.0 intake forum resize.jpg
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Staff member
lets do an example, using a common 454 BBC, and running through the math.
USE THE CALCULATORS to match port size to intended rpm levels... but keep in mind valve lift and port flow limitations[/color] ... ch_engine/

most big block heads will have either a 2.06",2.19" or 2.30: intake valve, if we take the fairly common 2.19" performance valves and calculating the throat restriction lets say at 90% of the valve diam. we find the actual port cross sectional area at the valve seat or throats about 3.1 sq inches.
if we look at a 454 , thats 56.75 cubic inches per cylinder , with a 2.19" intake valve and looking at this chart below we see a LCA near 103 degrees in a cam design, and a lift exceeding about .650 would be near ideal for max performance.
and yes with a bit of math, youll find the cam lobe acceleration ramp limitations almost mandate a roller lifter cam be used for max durability if your trying to get the required lift with a semi reasonable duration for performance street use.
now a quick verification of the intake port cross sectional area will also likely point to the fact that a larger oval port head is the best match.
use some snap gauges at the port cross sectional area and you rapidly find that the larger rectangle port heads are significantly larger in area at the intake manifold mating surface than at the narrower throat area.


now obviously youll need to tune the car to max power with the engine running in the condition and set-up how you intend to race the car, simply because changing the exhaust scavenging efficiency will mandate changes in the carbs jetting , power valve etc. in most cases to maintain the almost ideal 12.6:1 fuel/air ratio over the intended power band and thats sure to change if you vary the exhaust scavenging efficiency or back pressure.







Cylinder Pressure Note: youll generally want to try hard to maximize the useable compression as the higher the compression before you get into detonation the more efficiently the fuel can be burnt and the more torque the engine can produce, if limited to pump high test 92-93 octane fuel,165 psi # of cylinder pressure is about the best cylinder pressure for Iron heads with 92-93 octane, using pure un-ethanol laced fuel, gasoline. while the faster heat transfer rate of aluminum cylinder heads will usually allow 190psi # as the upper limit or best for aluminum heads.
While cheat sheets might have frowned upon in your sixth-grade classroom, we strongly encourage them in the garage, shop, or pits. That’s why we’ve put together this list of 13 key performance formulas you should know when building or tuning your street or race vehicle.
please let us know the parts list and machine work you have done,
and the eventual results you get and your driving impressions.
once the cars engine is installed and tuned and tested out.
you'll have much better results if you don,t randomly select parts,
and keep in mind a trusted machine shop, and listening too advice from an experienced machinist,
can help prevent you from a great many mistakes ,Try to find some friendly, knowledgeable older geezer,
with 30-45 plus years of experience building race engines

and if your going too build an engine for bracket racing,
you,ll want to get the static compression up to about 11.5:1-12.5:1 ( MINIMUM,)

and use race octane fuel, (do the required calculations) not crappy pump gas.
youll want to build the lightest weight car you can, because weight,
or increased mass takes more energy (hp) to accelerate,
building an engine to maximize torque over the intended rpm range,
and gearing the car too match that, and tuning the tires and suspension to use that available torque is key,
as it tends to maximize your cars potential. dynamic Comp Ratio.htm

Racing Carburetor CFM
Racing Carburetor CFM = RPM x Displacement ÷ 3456 x 1.1
Note: Summit Racing also offers this CFM Calculator to make the job easier.

Displacement = .7854 x Bore2 x Stroke x Number of Cylinders

Correct Compression Ratio (CCR)
CCR = FCR (Altitude/1,000) x .2
Note: You can also take this Compression Ratio Calculator tool for a spin.

Tire Diameter
Tire Diameter = (MPH x Gear Ratio x 336) ÷ RPM

Rocker Arm Ratio and Valve Lift
Gross Valve Lift = Camshaft Lobe Lift x Rocker Arm Ratio

Horsepower = (RPM x Torque) ÷ 5,252

Torque = (5,252 x HP) ÷ RPM

Rod Ratio
Rod Ratio = Rod Length ÷ Crank Stroke Length

Average Piston Speed
Average Piston Speed = Crank Stroke x RPM ÷ 6

Rear Gear Ratio
Rear Gear Ratio = (RPM at Finish Line x Tire Diameter) ÷ (MPH x 336)
Note: You can also save this link to a handy Gear Ratio calculator.

Volume (CCs) of Deck Clearance
CCs of Deck Clearance = Bore x Bore x 12.87 x Depth of Deck Clearance

Volume (CCs) of Head Gasket
CCs of Head Gasket = Bore x Bore x 12.87 x Thickness of Head Gasket















any of the performer or performer rpm heads will produce better power than the vortec heads on the 383 sbc is matched to that existing intake and nearly any reasonable cam selection, plus run cooler and weight less and be easier to repair or port if thats ever needed, that does not necessarily make them the only or best available option.

Look over the flow numbers very carefully.
Compare the flow at the lift matching your camshaft.

Some heads flow more at .500" compared to another head, but may flow less at .600"

DO NOT choose a head with larger ports than you need.

Horsepower is a function of RPM.
As such big horsepower numbers require high port flow.
If you are building torque for a street performance vehicle using overly large ports will result in reduced torque, poor acceleration.
This is because airflow through the port will be slower than desired.
The engine will come alive above 3500rpm, but if you are not revving it pass 6000 you will not realize the full potential of the ports.
Using a larger port works best with long duration and high lift camshaft and the use of a high speed torque converter.

Typically 180cc is considered as large as you would want for the average high performance street engine below 390cid.
A 400 to 420cid may work well with 200cc.
However aluminums heads such as the Air Flow Research street performance, Canfield and TrickFlow Twist Wedge heads all work very well with 195cc ports.
This is consider the result of more effective port design.
You will notice a larger port does not necessarily flow more.

While I do not attempt to favor one head manufacture of another,
AFR heads are consider by many to best the best performing overall.
They cost just a little more and until they get the new production shop up and running at full capacity, a set of Chevrolet heads must be order anywhere from 6 to 10 weeks in advance.

Flowing is a long list of heads you can compare. Look very carefully at the numbers and comments.
I will be more than glad to help you choice a pair of heads for your engine.

When trying to choose between an iron or aluminum head, consider the fact that aluminum dissipates head more quickly than iron. Retaining heat in the combustion chamber produces more power.
As a result the compress ratio needs to be high in an aluminum head to produce the same power output as an iron heads.
However, an aluminum head will allow you to raise the compression more than just the compensation requirement before pre-ignition or detonation (pinging) becomes a problem.
The result is additional horsepower and torque.

Maximum compression rations will vary due to attitude, octane rating of premium gasoline where you live, the camshaft duration and final drive ratio.
Building a motor with too high of a compression ratio will result in pinging which prevents further power increase and will over time pound out rod bearings and break ring lands. In extreme situation you may pound a hole through the top of the piston.
Running a compression ration .2 to .4 below the maximum recommended compression ratio for your application will only cost you 5 to 10 horsepower, but buy to a much longer running engine.

In studying head flow numbers keep in mind that they are only a guide. High flow numbers don't always equal more horsepower, and more horsepower doesn't always equal faster acceleration. It can be frustrating to choose the best head and the best camshaft for an application. So many choose, and all manufacturers cliam their product is the best. Dyno or track testing is the only real way to know for sure, but who can afford to do all that testing. I look to my experience the experiences of other engine builders, and magazine test articles to help, but that's all they are a help, until the engine is run, we all have to wait and see.

One last note. If you must pass a smog check your choices will be limited.
Some Edelbrock and TrickFlow heads are 50 State legal, carrying a CARB number.

Over the last few years coatings have become increasing popular. this is due to the fact that a coating can reflect heat back into the expanding gases during the power stroke.
This not only produces more power but will allow a higher compression ratio before detonation occurs.
Coating a piston cost about $20 to $25 each, but for the full effect to be realize you should also coat the combustion chamber and valves.
As a result of these added cost, this process is considered a premium for engine builds with a higher budget.

I can supply Mahle pistons for some applications (350s and 383s and some Ford engines) for about $550.

These pistons are very strong forging, come fully coated, are some of the lightest weight pistons available and have come unique narrow rings for less drag and more horsepower included in the purchase.
Ask for details.

The following is a reprint fro Chevy High Performance Magazine.




Intake Port cc & CFM @. 500" Lift

Chevrolet Production 441 Iron Head 155/201

The 882 head may have out-flowed this head but with the addition of larger 2.02-inch intake valves and some decent pocket port work these heads will out flow the 882’s. Keep in mind that with a small 155cc port volume these heads are great for making torque.


Chevrolet Production Iron 882 Head 151/205

This head had the smallest port size of all the heads we tested. A set of 2.02/1.60-inch valves can be swapped in but be aware that without blending in the short side radius, the results usually find lost airflow.

Chevrolet Production 462 Iron Head 156/212

This head was a small chamber head used on 327ci motors until the end of 1968. The flow can be improved a little with larger valves and port work but the additional cost of this is impractical in comparison to what you can by some other aftermarket casting for.

Chevrolet Production Vortec Iron Head 885 170/239

This head can be seen as a sleeper when compared to other GM production heads. It outflows the LT-1 aluminum Corvette head on the intake side, plus its mid lift numbers are very impressive. This head is perfect when iron heads are required. GM designed this head and put it on trucks as well as on the later Impala SS but with a different intake bolt pattern. As for production pieces these are one of our favorites.

Chevrolet Production L98 TPI Aluminum Head 163/196

This aluminum head was used on the Corvette TPI engines from the mid-Eighties until the LT-1 1992 motors were introduced. The 882-iron head out-flowed this head across the board. This piece is not our first choice for a performance head considering that the largest valve this head fits is a 2.00/1.55-inch combination and it has a 58cc chamber.


Chevrolet Production GM LT1 372 Aluminum Head 170/214

The LT-1 head was the next generation head developed for the small blocks after the L98 head. This head uses a reverse-cooling system, which means it can not be swapped onto older blocks. The 0.400-inch airflow numbers are great and with some port work, the addition of 2.00/1.55-inch valves can really wake these heads up.

Chevrolet Production LT4 Aluminum Head

The LT-4 is substantially different from the LT-1 casting, and the flow numbers explain why. The larger intake ports are definitely a contributing factor. For a production head these babies put up some pretty good flow numbers. Remember, like the LT-1 the LT-4 can only be used on a reverse cooling system block.
Chevrolet LS1 Aluminum Head 204/240

GM won’t be left out of category 3 with these heads. This head has great 0.400-inch lift numbers as well as a good E/I ratio. They also feature a more flat valve angle (15 degrees) in order to promote a better combustion chamber that’s shaped like a kidney to help direct combustion and reduce possible detonation. Remember that this head will not interchange with pre-‘93 small-block heads.


AirFlow Research 180 Aluminum Head 181/250
This head is the smallest of AFR’s line. It is intended for engines up to 350ci. The flow numbers are especially impressive on the exhaust side of this head, leading us to believe that a single pattern cam may be the best choice here. The E/I relationship is outstanding with and 84%, almost higher than any other head in this category.

AirFlow Research 190 Aluminum Head 191/262

This head has the best flow numbers of all the category 2 heads. Offering great flow throughout the entire lift range you can see this head doesn’t just put up one big number at maximum lift. If you’re looking for great flow from a mid-sized cylinder head this is definitely one of the top contenders.


AirFlow Research 210 Aluminum Head 215/271
Here is an extraordinary head. It has larger intake ports but with 240cfm at 0.400-inches of lift who cares? The E/I ratio is an incredible 75% making it hard to find anything wrong with these heads. This head may be a little much for a mouse motor but it is perfect for a big mouse somewhere in the 383 inch range up.
Brodix-8 Pro Aluminum 181/254

This head features larger 2.08/1.60-inch valves combined with a 181cc-intake port. With smaller intake port this head flows outstanding at 220cfm by 0.400-inches of lift and even better by 0.500-inches. Combined with a mid-sized port this, this is an outstanding choice for a strong 350ci or 383ci motor.


Brodix Track 1 Aluminum Head 216/246

The Track 1 head may be down on the numbers at 0.400-inch lift but it’s really competitive once it sees the 0.500-inch lift point. Add some short-side radius work and wow you’ve got a killer head. If you have a set of these heads there’s definite potential.


Brodix -11X 220 Aluminum Head 216/246

Brodix offers this large-port, 23-degree valve angle, small-block head as one of its largest ports in the stock valve-angle lineup. The low lift numbers are down a bit but in comparison to some of the others once the lift numbers increase you can see there is some serious airflow. These come available with minor or major port work depending on how you order them.


Brodix -1X Aluminum Head 223/278

The Brodix -1x heads feature a 40/60 valve spacing, meaning the centerline of each valve has been moved away from its standard location to accommodate a larger diameter valve and move both valves away from chamber walls for unshrouding. This means special offset shaft mounted rockers are needed and available from Brodix. It seems like a lot of R & D went into these bad boys and the numbers show it.


Canfield Aluminum Head 195/258

Canfield only sells this head with valves. One area to pay close attention to is the excellent low and mid-lift numbers. This head actually out-flows the Category 3 heads from 0.050- through 0.400-inches of lift.


Canfield 220 Aluminum Head 223/260

This race oriented small-block head requires the use of 0.150-inch offset intake rocker arm to accommodate the repositioned intake valve. The idea of spreading the valves apart is to increase valve diameter and improve flow. This head has 2.08/1.60-inch valves and probably works best on larger displacement mouse motors around 383-plus cubic inches.


Dart Iron Eagle S/S 165/210

Dart offers everything from street performance heads to full race heads. This Iron Eagle piece is the smallest head at 165cc port volume but its just what you need when building a stout street motor that sees occasional strip time. Compare its flow numbers to others and you can be the judge on this one.

Dart Iron Eagle 180 174/210

This head is also a big brother but to the 165cc Dart Iron Eagle head. The 180cc head reveals a respectable intake flow curve and an outstanding exhaust port. This head comes in many different combinations. You can order the head with straight or angle plugs, a 64cc or 72cc chamber, and in iron or aluminum. You will notice this head has better mid lift intake flow figures but the same full lift numbers as the 165cc heads, however the exhaust side flows better.


Dart Iron Eagle 220 220/258

The Dart Iron Eagle head here offers a budget alternative to the aluminum Conquest head. With similar flow numbers the only real big difference here is iron verse aluminum and cost. This head is offered in 200 or 220cc intake ports and with 2.02 or 2.05-inch intake valves.


Dart Conquest Iron 220 220/252

This head really likes to flow at lifts above 0.500-inches. The E/I ratio at 0.400-inch is a very good 72% and 68% at 0.500-inches. This head comes machined for both center-bolt and perimeter-style valve covers. The Conquest can be optioned with 200 or 220cc intake ports, valves up to 2.08/1.60, and in 64 or 72cc chamber sizes.

Dart Pro 1 Aluminum 215 221/253

This is perhaps one of the most versatile heads out there. While the low lift numbers don’t stand out, the higher lift numbers are on par with the rest of the heads on the market. This head is definitely best on high winding motors where consistent rpm is what wins a race.


Dart Iron Eagle 230 229/254

This is the largest of the Dart Iron Eagle series heads. They perform best on motors above 400ci-inches and with cam lifts above 0.500-inches lift. The E/I ratio is acceptable and the castings are made of good quality. These heads flow well and do not really require too much handwork to improve airflow.

Edelbrock Performer Aluminum 166/235

This head may first appear subtle in comparison to its flow numbers but don’t be fooled. The 166cc port makes for great torque and the E/I flow relationship is good. This head is perfect for a street/strip application. In our own personal experience we had a 355ci motor with 9:1 compression, a streetable Comp Cam (DEH 275), and an Edelbrock RPM manifold. With this combination we were able to achieve 420hp at 6,000rpm and 440 lb-ft of torque at 4,250 rpm.

Edelbrock Performer RPM Aluminum 170/237

The Edelbrock RPM head is the big brother to the Performer version. It still retains a small 170cc intake port volume providing great torque down low where it’s needed. The E/I percentage is no less than 70% with much higher numbers in the low-lift areas. This head is a step up from the Performer, flowing more air, which in return will make more power on the top end.

Edelbrock E-TEC 170 Vortec Aluminum 170/240
With the tremendous popularity of GM’s Vortec head, Edelbrock decided to design a head around the GM casting. This head features a 1.94/1.55-inch valve combination, and different port configuration allowing it to out perform the stock production Vortec head. However, the E-TEC heads are aluminum typically costing more than the production GM heads.

Edelbrock E-TEC Vortec 200/252

This head is the next step up from the smaller 170 E-TEC. It features larger valves and bigger intake ports. However, a Vortec style intake manifold must be matched with these heads. Up to 0.500-inches these heads don’t really out flow the stock Vortecs. On the other hand their exhaust ports are extremely efficient which help improve performance throughout the entire power curve. They are also aluminum, which can allow more compression with out detonation.


Edelbrock Victor Jr. Aluminum 219/255

This is an impressive head. It features a kidney shaped combustion chamber keeping the combustion moving, the flow is awesome from 0.400-inches all the way up to our tested 0.700-inches, and the E/I ratio is an amazing 81%. We see a head that flows some serious air and likes high lift roller cams.


Holley 300-570 Aluminum 172/232

This head from Holley comes with angled plugs and 69cc chambers, which are a big change from the stock 76cc smog chambers. The combustion chamber is typical of a late model design with a kidney shape that increases combustion turbulence lessening the possibility of detonation.


Holley SysteMAX Aluminum 186/242

This head is very similar to the -8 Brodix but it appears to flow a little better on the exhaust side. Again this head looks like it offers great torque potential with its well-proportioned 186cc-intake runner


Pro Action Iron 220 225/239

These heads can be purchased in many different intake port sizes. They are available with 180, 200, 220, and 235cc intake ports. They also feature a 64cc and 72cc chamber for your desired compression levels.


Pro Action Iron 235 Iron 245/242

These are the largest of the Pro Action lineup. The heads are advertised as 235cc intake ports but in our testing we found them to be 245cc’s. These heads are definitely for use on big mouse motors that like to see some rpm.


Trick Flow Specialties 195 195/250
These heads may not flow the biggest numbers but there should be little question regarding their performance that they can perform well. In CHP’s Nov. ’99 issue they were bolted on a mild 383ci motor and were able to pump up peak engine power by 15.5%. These heads offer some of the best power for the dollar on a mild small Chevy.


TFS Twisted Wedge 200/254

In an attempt to be different for the better, this TSF twisted Wedge head changed the valve angles from 23 degrees to 13 degrees. The really big difference here is what the exhaust side of this head is capable of. Only one other head (AFR 210) was even close on the exhaust side. The E/I was also a very respectable 77%. This head really can wake up your engine.


World Products Iron S/R Torquer 170/225

This head is very similar to the 882 head tested earlier. The valves are larger and the flow numbers at 0.400-inch lift are almost identical. At 0.500-inch lift the flow is up 15% over the 882 head. With prices to rebuild stock heads increasing all the time these heads would probably be one of your better investments.

spending a couple hours reading links and sub-links would do a great amount of good here and help sort out the problems, keep in mind that its a SYSTEM, what goes in is locked into the calcs
and all the math and related factors are well known, and easily calculated based on displacement, cam timing , exhaust back pressure head flow, exhaust flow , etc.






one of the most common and least tested, factors in most engine build ups is testing for restrictions to building increased horsepower. a huge problem is in restrictive exhaust systems that can not effectively allow the headers to scavenge the burnt gases from the cylinders, a good open collector on a well designed header can reduce the back pressure at the exhaust port to a negative pressure significantly increasing cylinder scavenging out the exhaust, thus helping draw in a fresh intake charge.
felpro # 1204=Port Size: 1.23" x 1.99"=2.448 sq inches

felpro # 1205=Port Size: 1.28" x 2.09"=2.67 sq inches

felpro # 1206=Port Size: 1.34" x 2.21"=2.96 sq inches

felpro # 1207=Port Size: 1.38" x 2.28"=3.146 sq inches

felpro # 1209=Port Size: 1.38" x 2.38"=3.28 sq inches

felpro # 1255 VORTEC=Port Size: 1.08" x 2.16"-2.33 sq inches

felpro # 1263=Port Size: 1.31" x 2.02"=2.65 sq inches

felpro # 1266=Port Size: 1.34" x 2.21"=2.96 sq inches

felpro # 1284 LT1=Port Size: 1.25 x 2.04''=2.55 sq inches

felpro # 1289 FASTBURN=Port Size: 1.30" x 2.31" 3.00 sq inches


the valve curtain area, cam duration and lift controlling that curtain area,or port cross sectional area will pose a restriction to air flow at some point,in the engines rpm band, but you can extend the effective air flow duration and efficiency with carefully timed exhaust scavenging, that helps draw in the intake runner inertia load of air/fuel,charge much more effectively if the peak negative pressure wave is correctly timed
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The Grumpy Grease Monkey mechanical engineer.
Staff member
have you ever taken the time, and effort,
too step back and grab a legal pad and pen, and logically make a reasonably complete list of the parts you,ll need,
and do the research required too list every part, (including all the small components like bolts, bearings gaskets) and their current cost, where you can find those components for sale, and part number, brand and supplier, and the phone numbers etc.
and call a local machine shop to get a better idea as to the labor cost of a project your looking into starting?
once you do theres commonly three things youll face,
the first is generally a sense of being over whelmed and depressed at the un-expected,total projected cost!
the second is a very common and strong temptation to either scrap the whole idea or to start substituting cheaper and generally considerably lower quality components that in the long run will eventually make the completed project either not worth owning and certainly something your less than proud to own.
and the third is the strong tendency to purchase parts that you find for bargain priced that either are not well matched to the intended projects goals, or nearly useless when matched to the project goals, but the bargain price seems nearly impossible to pass on.

all these tendency's result in a great many partly complete or abandoned projects, or projects that don,t resemble anything close to the original intent, or projects that never get started in the first place.
the completion of a well designed project will take some detailed planing and the ability to stick with the original projects part list and goals, and doing your research in detail, as to both the parts and machine shop costs, the time required and in many cases the tools that you might need,and of course youll need a place to work and store the project while its being built or repaired, well before you start buying components

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The Grumpy Grease Monkey mechanical engineer.
Staff member
grumpy, I,ve noticed that a great many of the links you post,
are too off site calculators, or charts based on calculators
do you really think those calculators are accurate?

If you break down that question your basically asking if
and if decades of hands on experience maters,

yes if you use valid info in those calculations,
and use data thats valid for the application,
you can reasonably expect valid answers
the basic rule applies,
a good example

might be one of the guys I built a 496 BBC engine for a few years ago
he didn,t seem to believe me when I said the cars engine
(built for street performance, not racing and with 3.36:1 rear gears,) had a certain horse power level,
(Id estimated 550 hp/600 ft lbs) and he was rather disappointed when his car with street tires and no suspension work only ran higher mid 12 second quart mile times.
he had a 1970 Pontiac

he had used an on-line calculator and used a car weight of 3450 lbs
the car actually weighed 4578 lbs with him in it

of course having reference books helps define the questions,
and understanding what info valid
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