basic intake manifold design AND selection info

grumpyvette

grumpyvette

Administrator
Staff member
info worth reading thru!, yes IM aware you don,t want to read all the linked info, but youll be amazed at the info contained in those links so its well worth the effort/time,
you might want to keep in mind that carbs are flow rated at 1.5 inches of mercury, heads at 28" of water and that anyone who has ever watched a vacuum gauge, will tell you the readings fluctuate rapidly, under most conditions and vacuum tends to vary with the cam,used the rpms the engines running, displacement and intake design,exhaust scavenging,ETC.
in most cases there factors are at least, mostly or on occasion, partly understood well enough that theres formulas and charts that can be used to define probable results, that parts selection will result in to a reasonable degree.

READ THE LINKS AND SUB LINKS AS ITS WELL WORTH THE TIME REQUIRED, yes I know thats a ton of info!, its a complicated subject, and theres several factors youll want to understand

viewtopic.php?f=52&t=322

viewtopic.php?f=55&t=1509

http://www.summitracing.com/expertadvic ... Calculator

viewtopic.php?f=55&t=2590&p=6662#p6662

viewtopic.php?f=38&t=1002&p=1804&hilit=shear#p1804

http://www.hotrod.com/techarticles/engi ... index.html

viewtopic.php?f=32&t=601&p=794&hilit=feeble#p794

http://www.compcams.com/Community/Artic ... 1737510521

http://www.popularhotrodding.com/engine ... index.html

viewtopic.php?f=55&t=431&p=530#p530

viewtopic.php?f=55&t=1038&p=4014&hilit=spacers#p4014

viewtopic.php?f=44&t=623&p=834#p834

http://www.fuelinjection.com/portinj.html

viewtopic.php?f=55&t=1038&p=1932#p1932

http://force-efi.com/weber.htm

http://www.strokerengine.com/TPIsystems.html

http://www.vintagespeed.com/index.htm

http://www.carburetion.com/tripower.htm

http://victorylibrary.com/mopar/intake-tech-c.htm

viewtopic.php?f=80&t=728&p=1915&hilit=+sensor#p1915

http://www.thecarburetorshop.com/Afterm ... setups.htm

http://www.corvettefever.com/techarticl ... index.html

http://www.eecis.udel.edu/~davis/z28/winter01/dyno/

http://www.fuelinjection.com/portinj.html

http://www.vetteweb.com/tech/vemp_0607_ ... index.html

http://ncarboni.home.att.net/NCtpi.html

http://victorylibrary.com/mopar/intake-tech-c.htm

http://www.velocity-of-sound.com/veloci ... lator3.htm

http://www.scottsautorepair.net/viewtopic.php?f=10&t=33

viewtopic.php?f=55&t=624

WATCH THIS
http://www.youtube.com/watch?v=N_ART4SBmdg


OK for the guys that don,t like reading ILL make this short and to the point,
when selecting an intake manifold the cam timing and compression ratio of the engine, and the header scavaging tunned rpm range should match the intended rpm band., IF it does, it simplifies intake selection.
IN about 80% plus of the cases Ive seen, if the rest of the combos set up too match the cam timing and head flow,rates, youll rarely see a single plane intake work well with a cam that has LESS THAN about 235-240 degs duration at .050 lift and youll rarely see a dual plane work as well as a properly set up single plane intake with a cam with over about 245- 250 duration at .050 lift or with a heavy nitrous shot.
It that 235-250 at .050 duration range that tends to be finicky on what works best.
naturally displacement , compression and gearing effect results, but if you read thru the three links above and do a few honest tests I think youll see as I have that those factors hold true much of the time!

viewtopic.php?f=55&t=823&p=1214#p1214


having the plenum divider fully in place below the carb base, tends to help lower rpm torque andcrisp responciveness to minor throttle possition changes, removing the divider effectively increases the plenum volume the runners draw from and that tends to slow low rpm responce to throttle changes but it tends of increase the flow rates slighly at high rpms so power in the upper rpm band tends to go up as the plenum volume is less of a restriction.
notching the divider tends to split the difference to some extent.
theres two basic carb spacer designs, they are comonly 1" or 2" tall, the one hole open spacer and the 4 hole designs, the 4 hole design in effect maintains the divided plenum, but adds plenum volume and reduces the restriction the limited space between the carbs venturies and individual intake runner entrances can have in some intake designs.
the open common plenum spacers are designed for use with single plane intakes where adding plenum volume helps upper rpm flow..
naturally you can mix/match and gain or loose plenum volume, and increase the distance from the carb base to the intake runners entrance, which can be helpful, especially if your installing a nitrous plate under the carb, or if your intake currently lacks plenum volume for your application.
as a general guide,and assuming your static compression ratio matches the cam duration you select, if your running less than about a 235 dur @ .050 lift cam, witha 2.57:1-3.36:1rear gear ratio, a dual plane intake should prove beneficial, have more than about 245 degrees dur. @ .050 lift, and a 3.45:1-plus rear gear and a single plane intake will generally prove useful.

you might find this of interest

http://victorylibrary.com/mopar/intake-tech.htm

keep in mind both the SUPER RAM and THE TPI, and clones can use several different bases from the stock intake designs and up to several different larger runner aftermarket bases and all runners won,t provide full flow potential, and the mix & match nature provides a great deal of variations, between designs, and the heads you match them too, the cam selected, and the headers also have a huge effect on your results
(weakest link in the chain, determines the max flow and power potential)
put a killer intake on crap heads,use the wrong cam, or gear the car for the wrong rpm band, or use a restrictive exhaust and you still get crap results, both the TPI and super ram can use the same base, so the runner length, diam. and plenum volume can change but if the base runners remain the same the flow is restricted to the lowest flow rate component used, and the components used with them,get the plenum and runners to flow 270cfm, and bolt them to a base that flows 210cfm, or heads that flow 210cfm, and the NET result is still 210CFM OR LESS
 
http://www.holley.com/data/HolleyNews/P ... 0H-243.jpg

holleys interactive carb selector

If you have questions about our products, need a part recommendation, or just cant seem to find what you need you can contact our Tech Support online and receive answers by e-mail.
Requests may be submitted at any time but please allow up to 48 hours for responses. All questions are answered in the order in which they are received.

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Earls Performance Plumbing technical support is availible by phone Monday through Friday 8AM to 5PM CST @ 270-781-9741.


READ THRU THIS ALSO

http://www.classictrucks.com/tech/cl_03 ... index.html

http://www.studebaker-info.org/Carbfile ... bselgd.pdf

http://www.fuelairspark.com/ezefi/default.asp

http://www.carcraft.com/techarticles/se ... index.html

http://www.popularhotrodding.com/tech/0 ... index.html
 
http://www.tpis.com/index.php?module=4_12_06

if youve got a newer LS series engine this might be of interest


heres a few hard to locate parts

http://www.deedsperformance.com/deedsv2 ... &Itemid=48

http://www.deedsperformance.com/deedsv2 ... &Itemid=48

http://www.centuryperformance.com/fueli ... g-140.html

PORT WORK CAN HELP

youll die of old age useing a dremel to port with....and keeping the burr wet with WD 40 helps a bunch

http://www.harborfreight.com/cpi/ctaf/D ... mber=93621

http://www.burrs4less.com/catalog/E_Ser ... g-8-1.html

http://www.diyporting.com/Shrouding.html

http://boosted.envy.nu/articles/porting1.htm

http://www.gmtips.com/3rd-degree/dox/ti ... t/port.htm

http://www.sa-motorsports.com/diyport.aspx

http://www.eecis.udel.edu/~davis/z28/buildup/plenum/

http://www.froadin.com/eng_mod_int.html

http://www.ws6transam.org/ported.html

http://www.gofastnews.com/board/technic ... l#post5343
 
LOTS of guys have both hood clearance issues and a desire to keep their hood looking stock, but want to run a healthy nitrous system, on their dual plane factory intake so they won’t need to add a hood scoop.

Ive tested a bunch of IMPROVE TPI REPLACEMENT style intakes on my cars, one of the best is the ported HOLLEY STEALTH RAM, but theres CLEARANCE ISSUES on some cars as its 10" tall and a corvette for example has only 9" of hood clearance so a CUSTOM PLENUM or a HOOD SCOOP is MANDATORY TO RUN ONE on a corvette for example !


If your going to use a single spray bar nitrous system under the carb, a high rise single plane with a direct line of site shot from the plenum to the back of the intake valve in the heads is the PREFERED route with NITROUS
I generally use this SBC intake.
hly-300-110.jpg

http://store.summitracing.com/partdetail.asp?part=HLY-300-110&autoview=sku

or this one
http://store.summitracing.com/partdetai ... toview=sku
hly-9901-101-1.jpg


no the injector bungs are not a direct fit to the fogger nozzles but it speeds the conversion.
nos-02001nos_w.jpg


http://store.summitracing.com/partdetail.asp?autofilter=1&part=NOS-02001NOS&N=700+115&autoview=sku

But since you’ve got clearance issues and choose not to swap intakes, you can EITHER have the divider in the dual plane plenum removed by almost any milling machine equipped machine shop and have a reasonable component that should function, reasonably well, or take a different route, like I point out below, I doubt the dual plane/single spray bar will be AS effective at fuel/air ratio control but it should function, and there’s lots of guys doing that, so its not doing something totally new. OR you can insure equal fuel/air distribution and decent power with a direct port nitrous set up. Where, you’ll have each intake runner equipped /with a threaded bung with its own fogger nozzle.
nos-02462nos_w.jpg


http://store.summitracing.com/partdetail.asp?autofilter=1&part=NOS-02462NOS&N=700+115&autoview=sku

on BBC engines I’ve generally used the HOLLEY EFI intakes as they are pre set up to some extent.
hly-9901-209.jpg

http://store.summitracing.com/partdetai ... toview=sku
IF you don’t remove the plenum divider in the dual plane intake plenum, there’s a BETTER chance of having distribution issues but there’s lots of guys doing it successfully so it can be done, only testing will tell.

BTW MOST FOGGER NOZZLES ARE THREADED FOR 1 /16" N/P THREAD,(HARD TO FIND IN HARD WARE STORES) so youll still need welding or epoxy to ger them adapted & installed
youll need the correct thread tap

http://www.victornet.com/cgi-bin/victor ... 00,803,613

yes, with minor clean-up and runner matching thats one of the MOST COST EFFECTIVE combos to increase the TPI flow, both the SLP runners and the EDELBROCK BASE can be improved thru minor porting but both together easilly out flow the stock system, and with minor port clean-up can flow equal or better than the super ram many guys use and personally I found it produced better results once I ported the base,runners and plenum

the answer to that totally depends on the parts you select , how they get ported and the rpm range you operate in,the cam, compression ratio, heads selected and rear gear ratio
displacement even the transmission will effect the sweet spot in the power band and the two intakes have a different power band, so matching the gearing to take full advantage of the peak power/torque vs running higher or lower effects results

DO NOT SIAMESE THE INTAKE PORTS IN THE BASE!!!!!
repeat!! DO NOT SIAMESE THE INTAKE PORTS IN THE BASE

GREATER GAINS ARE FOUND SIAMESEING THE UPPER 1/3 OF THE SLP RUNNERS AND PLENUM OPENING AREAS AND OPENING THE RUNNERS TO THE MAX





http://www.thirdgen.org/newdesign/tech/coolantbypass.shtml

http://www.eecis.udel.edu/~davis/z28/buildup/plenum/

http://www.eecis.udel.edu/~davis/z28/winter01/dyno/dyno010511/webpage010511.html

http://www.bfranker.badz28.com/96ss/58porting.htm

http://216.121.161.76/files/PlenumPorting.pdf

http://www.gmtips.com/3rd-degree/dox/tips/buff/plenum/pol-plen.htm

http://www.gmtips.com/3rd-degree/dox/tips/plen-port/port.htm
 
yes reading thru the info is worth the effort
http://www.prosystemsracing.com/catalog.html

http://www.wilsonmanifolds.com/shop/

heres a few usefull things

http://en.wikipedia.org/wiki/Intake_man ... e_manifold

http://www.popularhotrodding.com/engine ... index.html

http://www.circletrack.com/techarticles ... index.html

http://victorylibrary.com/mopar/intake-tech-c.htm

http://www.sdsefi.com/techinta.htm

http://www.carcraft.com/techarticles/03 ... index.html

http://www.gmpartsdirect.com/performanc ... D=995.html

obj104geo105pg1p2.jpg

DSCN0086.jpg



http://www.carcraft.com/techfaq/ccrp_07 ... quads.html

http://www.chevyhiperformance.com/howto ... index.html

http://www.popularhotrodding.com/tech/0 ... index.html

http://www.edelbrock.com/automotive_new ... hevy.shtml

http://www.vetteweb.com/tech/vemp_0607_ ... index.html


single 4 barrle carb intakes are much easier to tune in most cases but for an older more experianced guy, who can tune carbs and linkage you might be surprised at what those (OLD OUT OF DATE DUAL QUADS CAN DO)

yes IM fully aware, that if you were like most kids growing up in the 1960-1980,s in america, the older kid next door when you were younger threw a 4 barrel intake, headers and a off track Z28 cam in his camaro and it loped like a dragster and was scarry fast when you were younger........yeah! it was faster but probably no where close to the 500hp he bragged about!


ID suggest you start by reading thru these

http://www.amazon.com/Build-Performance ... 714&sr=8-2

http://www.amazon.com/Small-Block-Chevy ... 799&sr=8-7

http://www.amazon.com/Smokey-Yunicks-Po ... 894&sr=8-2


http://www.rustpuppy.org/chp/

http://www.themotorbookstore.com/resmchstvi.html

http://airflowresearch.com/articles/article031/A-P1.htm

viewtopic.php?f=46&t=460

http://www.virtualengine2000.com/

viewtopic.php?f=69&t=780

http://www.chevytalk.org/fusionbb/showt ... id/131229/

http://www.powerperformancenews.com/for ... w-230.html

viewtopic.php?f=52&t=796

viewtopic.php?f=52&t=181

viewtopic.php?f=52&t=904

and you can cut out a dual plane intakes center plenum divider under the carb venturies,effectively increasing the plenum volume, if you want to increase the upper rpm flow rates at the cost of a loss in low rpm responsiveness

cutplenumdivider.jpg
 
basic intake & porting related info

http://www.circletrack.com/techarticles ... index.html

http://www.hashmarks.com/techtips/intak ... orting.htm

http://www.vetteweb.com/tech/vemp_0805_ ... index.html

http://www.vetteweb.com/tech/vemp_0805_ ... to_18.html

http://www.hotrod.com/techarticles/engi ... index.html

http://www.hotrod.com/techarticles/engi ... chart.html

http://www.j-performance.com/index.php? ... view&id=27

http://www.j-performance.com/index.php? ... view&id=18

http://www.j-performance.com/index.php? ... view&id=20

http://www.j-performance.com/index.php? ... view&id=19

http://www.j-performance.com/index.php? ... view&id=21


http://www.highperformancepontiac.com/t ... c_gto.html

http://www.maximumraceengines.com/intak ... rting.html

http://www.allpar.com/fix/holler/porting.html

http://www.highperformancepontiac.com/t ... sults.html
 
if you want to do some minor port and bowl clean-up work heres a few pointers or tips
http://www.harborfreight.com/air-die-gr ... 99698.html
these HF extended die grinders are in my opinion a great deal, they cost $16-$20 depending if you catch them on sale and last long enough to port at least two sets of cylinder heads, they are a disposable item like the burrs they spin, but dirt cheap and well worth the cost
12256.jpg

http://www.sa-motorsports.com/diyport.aspx
you can order this set of these long carbide burrs for about $36-$40

http://www.mcsdepot.com/browseproducts/ ... REACH.HTML
NS10033.jpg

btw hard stones should NEVER be used on aluminum as the clog, bind and shatter

http://www.carbideselect.com/burshpescuts.php

(1)dremels won,t cut it!, hard stones won,t work, USE GOGGLES, and spray the carbide BURR with WD 40 FREQUENTLY as it tends to reduce the tendency to GALL and cluster chips

(2) get a cheap die grinder , and 1/4" LONG SHANK carbide cutting burrs or two and thier DISPOSABLE like sand paper

http://www.harborfreight.com/cpi/ctaf/d ... mber=36572

http://www.carbideselect.com/burshpescuts.php

http://www.american-carbide.com/Burs/OQB.php

http://www.american-carbide.com/Burs/PCB.php

http://cgi.ebay.com/24-pc-Steel-Burr-Bu ... 7C294%3A50

generally youll want to reduce the width of the casting around the valve guides, smooth the transsition from the port to the valve seat, and open up ports to the gasket size on the port enterance, youll want to remove casting flash and generally smooth the abrupt angles, get a couple books on porting and follow the advice carefully.

small changes that are easily done by home porting can result in gains of 10-20 hp if both the heads and intake are carefully cleaned up.

read
viewtopic.php?f=52&t=333&p=1764&hilit=throat#p1764

http://www.chevyhiperformance.com/techa ... index.html

http://www.bfranker.badz28.com/96ss/58porting.htm

http://www.cmc.net/~xero/gtpin.html

http://www.mirage-performance.com/tech/porting.html

http://www.chevyhiperformance.com/techa ... rting.html

http://racingdownloads.com/racing_software-4.html
 
http://www.classictrucks.com/tech/0404c ... index.html

The Hows and Whys of TPIs
The Most Asked Questions Answered
By Thomas P. Iverson


There aren't too many things more misunderstood to many of us than fuel injection. Although carburetors haven't been used on new cars since the mid-'80s hot rodders haven't moved as quickly. There's no denying that a well-tuned fuel injection will perform better than a carb, but there's still a stigma left by some of the early aftermarket kits that left a whole lot to be desired.

One of the best ways to retrofit fuel injection is to still take advantage of the research General Motors put into it and find a used factory system. The Tuned Port Injection (TPI) units of the mid '80s to early '90s are still some of the best and easiest to do. In an effort to take some of the mystique out of upgrade to this "new" technology, we got together with the folks at Street & Performance to get some of the most common questions we get asked answered. We'll be following this article with an actual installation, hopefully, next month.

1. Why should I swap to fuel injection?
Swapping to fuel injection has many advantages. Your engine will last longer and have better low- and mid-range torque. The computer will keep the air/fuel ratio correct even when changing altitude, which not only provides better driveability, but improved fuel mileage.
2. Can I get a Tuned Port Injection unit out of salvage?
Yes, the only part to wear out is the shaft in the throttle body which can be replaced with a larger aftermarket throttle body or a new factory unit.
3. What vehicles should I look for as good donors?
The '85-92 F-bodies (Camaros, Firebirds, and Trans Ams) will be the most plentiful, but '85-91 Corvettes are also out there now at reasonable prices. The Corvettes were all 350 V-8s. The '85-86 F-bodies were 305s and the '87-92 were either 305s or 350s.
4. Will the TPI intake manifold bolt onto my earlier heads?
The '85-91 Corvettes and '85-86 F-bodies all have the early bolt pattern. The '87-92 F-bodies have the late intake bolt pattern, but can be interchanged, or the two center bolt holes can be modified to fit early heads. Street & Performance will trade or modify them for you. If you have the new Vortec of Fast Burn heads, S&P can supply intakes to work with these as well.
5. Do I need to find a complete unit or can I piece one together?
Ideally you want to find one as complete as possible, but you can piece one together. Most parts interchange, but not all. There are lots of TPI units on ebay if you're looking to keep your hands clean, or you can look in salvage yards as the TPI-equipped vehicles are old now and are hitting salvage yards regularly. The S&P team can help you, or you can send your unit to them and they will interchange the parts with their own or new GM parts. S&P also offers complete units set-up for your engine (283-406ci or beyond) and transmission (automatic or manual) in three finishes (natural, polished, and chromed).
6. How much should I pay for a unit?
If you find a used but complete unit expect to pay from $150 on the low side to a high of $500.
7. How can I tell if it's a 305 or 350 unit?
The injector numbers are the only way to tell. A GM dealer or S&P should be able to tell you which ones you have. All Corvette units were 350s. All '85-86 F-bodies were 305s, but the '87-92 F-bodies could be 305s or 350s.
8. What's the difference between the Corvette unit and F-body unit?
On all Corvette units, the fuel rails come out on the passenger side. On all F-body units, the fuel rails turn and come out on the driver side. The fuel rails can be modified for rear exits with fittings supplied by S&P.
9. Can I reuse the old injectors, or do I need to get new ones?
The '85-88 injectors can be cleaned with S&P's ultrasound system and made like new again. They have new performance screens and all other parts to service the injectors. S&P recommends replacing the '89-92 multi-tech injectors as they have had a lot of problems.
10. Is there anything I can do about the dents in my runners?
S&P can straighten them and make them like new most of the time, or they can supply new or reconditioned ones for whichever year you need. Aftermarket larger runners are also available that will supply the engine with more air and allow you to pick up some horsepower.
11. Can the fuel-injection unit be too big for my engine?
An engine is like an air compressor. The easier it breathes, the more power it will make. Porting the intake, adding a larger throttle body and runners, and higher flow injectors will help a high performance engine. But, just as a high- flowing carburetor can be too big for a mild to stock engine, so can the fuel injection. Go too big and the torque will start to drop.
12. What is a Mass Air Flow (MAF) meter?
The MAF is an air meter that is in the air induction tube leading to the throttle body that measures the amount and the temperature of the air going into the engine.
13. Can I run the old computer?
Yes, but the '85-89 computers were all mass air flow (MAF), which is expensive and is susceptible to damage by dirt or water (new GM replacement is about $300). Plus it can get in the way when trying to fabricate a custom air intake to fit a specialized installation. The '85s used the #1226870 computer only one year, and '86-89s used the #1227165 computer. Also the '85-88 used a ninth injector for cold start. The '89s used the same computer as '86-89 but fired all eight injectors for cold start like the '90-92s.
14. What is the ninth injector?
The '85-88 units have a ninth injector on the driver side of intake that fired one injector on the side of the intake for cold start only. The fuel then has to travel down each runner under the intake. The '89-up computer fires all eight injectors right on top of the valves so that you get better cold starting.
15. Can I disengage the ninth-injector cold-start function?
Yes, by using the '90-92 speed density computer, you will use all eight injectors for cold start.
16. Why should I change to speed density?
Speed density is preferable for many reasons. First, although the TPI units through the years remained about the same, the computers kept getting smarter. GM hasn't updated the '85-89 MAF computer in years. But they just updated the speed density computer in mid 2003. Speed density, uses the Mass Air Pressure (MAP) sensor because it's more dependable and only has a four-wire hookup (key, starter, ground, and fuel pump). Speed density also provides better mileage, performance, and drivability.
17. How do I get a speed density computer?
Speed density computers were used on '87-up four-cylinder and six-cylinder cars and '90-92 V-8s. Look for computers with these numbers #1227730, #16198262, #16196344, and #8889196 and weather-proof computer #1227727 and #16198260. You can also still get one through GM or some aftermarket companies.
18. Can I use a four-cylinder or six-cylinder computer?
Yes, they're all the same but will need to be upgraded with a chip designed to work with the V-8. Just be careful not to get a V-8 chip that has the Vehicle Anti-Theft (VAT) protection built into it. VAT will only let the vehicle run for two seconds then shut down the injectors--not allowing fuel to get to the engine. Most 305 chips don't have VAT, but all 350 chips do.
19. Can VAT be taken out?
Yes, if you have a V-8 speed density chip, S&P can reprogram it for your application.
20. Can I mount the computer in the engine compartment?
Only if you use the '90-91 Corvette computer (#1227727).
21. Why should I reprogram the chip and not just use it?
Because the vehicle will perform better and have better drivability because the chip will be programmed specifically for your vehicle's transmission, rearend ratio, and tires.
22. Why use a GM computer and not an aftermarket programmable one?
The chip in the GM computer can be programmed for just about everything you want to do. If you want to build a stroker 383-406, the chips can deal with it. GM spent a lot of time and money developing computers and updating them, and they know what they are doing. They use the latest technology and you can get a replacement anywhere if the need ever comes up.
23. Can I put 305 injectors on a 350?
If your engine is not over 250 horsepower, you can put an S&P adjustable fuel-pressure regulator on it and raise fuel pressure. Plus when you get your chip programmed, you can tell the computer you are running 305 injectors on a 350, which will lengthen the pulse width to let more fuel to the engine when needed. Engines with 250-300 horsepower need more fuel, so they'll need to run 21.9 lb-hr injectors.
24. What size injectors did the factory use?
The 305s came with 19.9 lb-hr injectors. The standard 350s came with 21.9 lb-hr injectors, and the LT1 350s had 24.9 lb-hr injectors. The 300-400hp engines should run 24.9 lb-hr injectors.
25. Can I use LT1 injectors in my TPI?
Yes, but be careful. S&P has had a lot of problems with LT1 injectors when they have sat for a while.
26. Is there an advantage to chroming the TPI unit?
There are no performance gains, but it depends on if you're looking for style as well as performance. The natural as-cast finish is hard to clean. The polished finish looks good when freshly polished, but you have to maintain it to keep it looking good all the time. The chrome units offer easy maintenance--just spray on some Windex and wipe it off.
27. How big of cam can I use?
You can run a high-lift cam, but it'll need a wide lobe separation and be able to provide at least 13 inch or more of vacuum.
28. Do I need to use a special fuel pump?
An in-tank fuel pump is best because the pump is kept cool by the fuel in the tank, and they run quieter. The in-tank units don't have to work as hard as the exterior pump because they just to have to push the fuel. A lot of the late-model in-tank pumps will fit into older tanks, (S&P can help you determine if yours will work) or you can check with companies like Rock Valley, Tanks, No Limit, and others who sell new tanks designed for the in-tank pumps. You can use an external fuel pump. They work okay if properly mounted--which is close to the tank away from heat.
29. How much fuel pressure do I need?
You need 38 to 48 psi for a 300- to 400-hp engine. High horsepower engines need 40 to 48 gallons-per-hour of fuel. You don't want to use a racing-type pump because they push too much fuel, and the TPI regulator cannot push it back to the tank fast enough.
30. Can I swap to fuel injection myself or do I need a professional shop?
It depends on how mechanical you are and how comfortable you are with your skills. The wiring harness only has four wires to hook up (ignition switch, fuel pump, starter, and ground). Most of the rest of the job is the same as swapping any other intake manifold. CLASSIC TRUCKS will soon be running an install story showing a 17-year-old retrofitting his pickup with a TPI. S&P has videos available to help walk you through it as well.
31. What wiring grounds do I need to make sure I have?
The battery needs to be grounded to the engine or transmission, and the engine needs to be grounded to the frame. If a ground is bad, you will have poor starting and poor drivability. You'll also need a battery with at least 850 cranking amps and a 90-amp or higher alternator.
32. Do I need to use an oxygen sensor?
Yes, the oxygen sensor lets the computer keep the fuel ratio at 14.7:1 for good fuel economy and performance. You'll need to install one in the exhaust somewhere (single wire with short headers, three-wire heated sensor with full-length headers). The oxygen sensor needs to stay at 600 degrees, and the 12-volt wire of the 3-wire heated sensor will keep it hot so the computer goes into closed loop mode quicker--which will give you better drivability.
33. What distributor can I use?
Use the '85-91 Corvette or '85-86 F-body large distributor with the coil. If you need a smaller unit, the '87 and later F-bodies used a small distributor with a remote coil. If you are using the '85-86 distributors with a roller cam, you need to change the distributor gear to the appropriate GM gear (PN 10456413) or an aftermarket one.
34. Do I need special intake gaskets?
With aluminum heads you need the gaskets for the late-'86-91 Corvette if you are going to run the water-crossovers (the intake has outlets from the back of the heads to let water out to keep from getting hot spots). Cast iron heads can use the '85-92 F-body gaskets.
 
RUNNERS FLOW
viewtopic.php?f=55&t=1509

Runners only (measured individually)
Stock....................203.17 cfm
ACCEL................242.02 cfm
Extrude/ACCEL...275.83 cfm
Super Ram............289.18 cfm
Intake manifold with 3/8 inch radiused intlet
.............................222.45 cfm
Stock TPI intake manifold with runner
Stock....................198.72 cfm
ACCEL................213.52 cfm
Extrude/ACCEL....217.11 cfm
Super Ram............220.67 cfm
ACCEL Hi-Flow intake manifold with 3/8 inch
radiused inlet.........251.51 cfm
ACCEL Hi-Flow intake manifold with runner
Stock....................215.83 cfm
ACCEL................232.53 cfm
Extrude/ACCEL....243.21 cfm
Super Ram............240.24 cfm
Extrude-Honed ACCEL Hi-Flow intake
manifold with 3/8 inch radiused inlet
............................275.83 cfm
Extrude-Honed ACCEL Hi-Flow intake
manifold with ACCEL runner
............................266.94 cfm
Edelbrock Performer RPM manifold
(Stock)..................286.51 cfm
Edelbrock Victor Jr.
.............................275.24 cfm
STOCK CHEVY CROSS FIRE manifold, no balancer holes:
176 CFM @ 28" (with lid AND swirl plates installed.)
Mildly ported intake
192 CFM @ 28" (with lid AND swirl plates installed.)
Mildly ported intake
199 CFM @ 28" (with lid but without the swirl plates.)



HOLLEY Stealth ram
Stock, mild port work-----------------------------275cfm
Ported extensively-----------------------------------298 cfm





INTAKE MANIFOLD RUNNER LENGTH FROM VALVE SEAT TO PLENUM

STOCK TPI MANIFOLD------------------------------------------------------------- 8
ACCEL TPI MANIFOLD-------------------------------------------------------------- 8
EDELBROCK PERFORMER RPM RUNNER LENGTH-------------------------. 6
EDELBROCK VIC JR PASSAGE LENGTH------------------------------------------- 5.5
RUNNERS
STOCK TPI---------------------------------------------------------------------------.11.25
ACCEL HIGH FLOW-------------------------------------------------------------------11.25
ACCEL SUPER RAM RUNNER LENGTH----------------------------------------------7
Total runner lengths INCLUDING PLENUM TO VALVE SEAT
STOCK TPI-----------------------------------------------------------------------------25.375
ACCELL HIGH FLOW----------------------------------------------------------------25.375
EDELBROCK RPM ---------------------------------------------------------------------.12.125
EDELBROCK VIC JR--------------------------------------------------------------------11.675
HOLLEY STEALTH RAM-------------------------------------------------------------12.125
Lt1/lt4----------------------------------------------------------------------------------9.0
TPIS MINI-RAM---------------------------------------------------------------------.9.5
ACCEL SUPER RAM RUNNER LENGTH-----------------------------------------.21.0


http://www.rbracing-rsr.com/runnertorquecalc.html

RUNNER CROSS SECTIONAL AREA
HOLLEY STEALTH RAM STOCK------------------------------------------------------.2.3 SQ-
EDELBROCK VIC JR -----------------------------------------------------------------------.2.09 SQ
EDELBROCK SUPER VIC -----------------------------------------------------------------.2.3 SQ
 
ALL INTAKE Manifolds Ive seen ,REGARDLESS OF BRAND REQUIRE some clean up WORK of the rougher casting areas,or slight modifications or port matching to maximize the potential, IVE used offenhauser,INGLESE, GM performance, EDELBROCK,DART,BRODIX,WEI AND,and CROWER, HILBORN, KINSLER intakes THEY ALL NEED MINOR WORK if you want them to work correctly, like setting the gap on spark plugs, you can install them out of the box, and they usually work, or do whats required to get them to their full potential.
PortMatch02.jpg

PortMatch03.jpg

PORT MATCHING THE INTAKE RUNNER EXIT TO THE CYLINDER HEAD PORT ENTRANCE USUALLY HELPS REDUCE RESTRICTIONS TO FLOW RATES, AND REDUCES FUEL/AIR DISTRIBUTION ISSUES
http://www.automedia.com/Port_Matching_ ... 040801pm/1

http://www.circletrack.com/techarticles ... index.html

http://performanceolds307.tripod.com/id29.html

http://www.amazon.com/How-Build-Horsepo ... 1884089143
worth reading
61-srHbK4OL._SL500_AA240_.jpg
 
Last edited by a moderator:
http://www.lubkerdist.com/guidepdf/Socketspipedry.pdf

http://www.amazon.com/Moroso-39152-Chro ... B000COS54C

http://www.engineeringtoolbox.com/npt-n ... d_750.html

youll need to use PIPE PLUGS in some applications to block off un-used sensor mount locations, be sure to use a sealant on the threads and only tighten them as much as required to seal, as they are tapered and can crack heads and intakes if over tightened

now Ive been asked many times if a STEALTH RAM, MINI RAM OR A single plane EFI intake is the best choice?
thats a good question, and Id say the answer changes with the amount of work your willing to do, and the application you use the intake in,a custom stealthram can easily provide more power potential than your average hot rodders looking for,for street use, (500hp or so)but in general Id say that the single plane intakes, with a 4 barrel throttle body design, once correctly matched to your heads will provide the best results, in the power range your looking for.(500 and less hp) simply because of clearance issues and ease of setting up the intake.
obviously if your trying to maintain a semi stock appearance theres other options
hly-9901-107_w.jpg

hly-9900-172_w.jpg

hly-9900-171.jpg


ID suggest you read thru the threads and sub links

http://www.gmhightechperformance.com/te ... index.html

viewtopic.php?f=55&t=431&p=1409&hilit=stealthram#p1409

viewtopic.php?f=55&t=1745&p=4381&hilit=stealthram#p4381
 
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