whats it really take to run reasonably fast in street trim

grumpyvette

Administrator
Staff member
whats it really take ?
, well a decent transmission,rear gears ,suspension and tires sure helps,

but its basically dependent on your having a high hp to weight ratio,matching the cars tires and drive train gearing to the engines power curve, and how effectively you get power to the ground, how well your brakes and tires can transmit the power to the pavement and how well the suspension and brakes allow you to control the cars speed, direction cornering and de-acceleration, that matters.
any car with 400-450-plus horsepower at the rear wheels and a power to weight ratio, under about 7 lbs per horse power should produce exciting performance, but remember that the less that car weights the more impressive that performance, in both acceleration and braking will be, and the easier the car will be to stop or control under abrupt changes in direction,, and the less your cars total weight the easier it will be to accelerate or stop it faster, and lower weight also tends to result in lower parts wear and breakage rates, on the suspension and drive train and brakes,
its excess WEIGHT that is the biggest problem most production cars are fighting and why the T-buckets and A.C. cobra and similar kit cars can due to much less weight easily produce better performance.
I think most of us have run into a great many similar choices, between buying tools and auto parts,
its simply the result of a limited budget ,in most cases,
and most of us make a few mistakes ,
but as long as you keep the goal of building the car in mind you'll do ok.
after you gain experience there's both engineering and art involved in the process,

you'll generally start with a goal, you've envisioned for your car, reality and physics will provide some of the limitations, you'll be limited to a budget and at times by your access too tools and limited by your skills and knowledge, youll generally start,by simply making a very detailed list of the components you want too use ,to upgrade and modify the car to gain the performance and look of the car, and once you have that list of components, and being forced by going back through that detailed, list and doing the required math too verify you have selected the correct matching parts, and when you find you have to change a few components you go back, change the list and again revue the math, most of us start out without the required knowledge to accurately match parts and your goal.
yet this process forces you to do some research into what you can reasonably accomplish with the tools and skills you have and the realization that you may need to acquire both skills and more tools as you proceed.


your engines power potential is mostly related to the displacement, and cylinder head flow rates and components that effect those cylinder head flow rates,compression, exhaust scavenging , etc. parts like intakes,headers and cam timing.
When you start seriously think about getting into the 10's and even 11's it's not only the HP that needs to be there, but you need to start having your converter,stall speed, rear gear, ratio,transmission gearing, ignition,timing curve,and some sort of traction aid device,and tires all dialed in. The 60' time is something you should focus on and will help greatly. Also, you need to start thinking about, total weight, weight transfer and suspension and frame so a roll cage and your suspension set up, tend to be critical.

I always get a bit of a grin when most guys bring up WEIGHT as the reason they don,t want to swap from a SBC to a BBC engine, Id be the last person to say weight doesn,t matter but be reasonable and think things through carefully, deal in known facts, and verify what your dealling with, don,t guess or assume!.
if you do a bit of research the difference between a all iron sbc and a BBC with an aluminum water pump,intake and heads is negligable (READ THROUGH THE LINK)

http://garage.grumpysperformance.co...asic-engine-size-measurements-weight-info.11/
lackoftallent.jpg

heres a good example of what to expect when a less than experienced throttle foot and 500 horse power potential cross paths in the real world.... it takes TIME and PRACTICE to learn to drive a powerful car that can easily turn the tire traction to smoke with the blip of a throttle

I especially get a big grin when the same guys tell me with a strait face that thier camaro or corvette weights something like 3300 lbs,with them in it!
I ask them if they have ever actually bothered to have the car weighed with them in it and so far all Ive ever seen is a blank stare or that deer in the head lights look!
honestly, step one weight your car, with you in it!
so you know what the facts are, then consider this,
lets say your corvette weights 3600 lbs with you in it,
the small block engine in it lets guess and say 550 lbs, if you swap to a big block, with aluminum heads its going to be 30-50-lbs heavier, its heavier but consider this
if that SBC is a decent engine, lets say a well built 383 it will make about 1.3 hp per cubic inch of displacement or about 450-500 flywheel hp, a BBC generally has better heads, bigger valves and if you built a similar BBC , (.030 over bore and a .25 inch stroker crank, like that 383 built from a 350 sbc) out of a 454, youll get a 489 cubic inch displacement BBC
its easily able to make a similar 1.3 horse power per cubic inch of displacement, or near 600-630hp,
if the car weights 3600 lbs with a sbc and we divide that by the 500 hp we get 7.2 lbs per hp, add 50 lbs to the car with a BBC and lets say only 575 hp,your still at 6.35 lbs per hp, or still about a 13% advantage in power to weigh ratio.


http://www.wallaceracing.com/et-hp-mph.php

http://garage.grumpysperformance.co...asonably-fast-in-street-trim.3404/#post-41457

We've all been there, starting with a car that goes 13's or 14's and slowly making improvements and going faster.
heres a few calculated, averages, based on a car weight of 3600lbs

which will be close to many street cars (car & driver) and based on REAR WHEEL HORSEPOWER, not flywheel hp

car weight....hp.......E.T......MPH
3600...........300......13.33..100.5
3600...........400......12.12...110.5
3600...........500.......11.12...119
3600...........600......10.6......127


now lets reduce the weight to 3200lbs,
to simulate a car stripped of most non-essential weight
notice what the removal of weight gains you in performance

car weight....hp.......E.T......MPH
3200...........300......12.8..104.5
3200...........400......11.65...115.5
3200...........500.......10.82...124
3200...........600......10.2......131


now lets suppose you build a T-bucket, or COBRA KIT CAR that weights only 2800 lbs, (an easy to reach weight, in that application)

car weight....hp.......E.T......MPH
2800...........300......12.3..109
2800...........400......11.14...120
2800...........500.......10.32...129
2800...........600......9.75......137
http://www.wallaceracing.com/et-hp-mph.php

http://garage.grumpysperformance.com/index.php?threads/estimate-horsepower-from-trap-speeds-et.1814/

your sure to find these threads of interest

READ THROUGH THIS LINK
http://garage.grumpysperformance.com/index.php?threads/finding-a-machine-shop.321/



http://garage.grumpysperformance.com/index.php?threads/another-496bbc.5123/

http://garage.grumpysperformance.com/index.php?threads/matching-parts-and-a-logical-plan.7722/

http://vexer.com/automotive-tools/1-4-m ... calculator


http://garage.grumpysperformance.com/index.php?threads/454-bbc-on-the-cheap-well-to-start.11739/
 
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Re: whats it really take to run reasonably fast in street is almost mandatory
https://books.google.com/books?id=8r7ODgAAQBAJ&pg=PA30&lpg=PA30&dq=afr+dyno+tests&source=bl&ots=3Ht-yG4ZRv&sig=Xi7gmbzwLem8t_g1TygdZr7z84I&hl=en&sa=X&ved=0ahUKEwjN0LSDjt3WAhVDx1QKHRulDRY4HhDoAQhhMAk#v=onepage&q=afr dyno tests&f=false
I've got to step back and just bite my tongue at times when I see some guys cars,
and listen to them explain what they want to do,

knowing the budget they have to work with and the rather UN-realistic expectations.
If you have experience and a decent cash flow to throw into a project you can accomplish some rather surprising results, but a great deal comes down to the limitations imposed by the cars weight and the engine displacement and the amount of cash thats available to throw into the quest for speed or performance, and if you start with a heavy car and a rather small engine displacement and a very limited budget your working at a huge disadvantage.
yes you can have a decent performance car on a tight budget , but it takes careful planing and the realistic look at your options and you need to think things thru and plane carefully. if you know your working with a limited budget you want to realize that working with a small and fairly light weight car with a common engine has advantages.
a few days spent in doing in depth research into matching the required drive train, fuel, cooling, lubrication, suspension, engine lubrication, and brakes on a car can help you avoid a great many potential problems
going FAST is mostly about GETTING YOUR TRANSMISSION GEARING TO MATCH THE ENGINES POWER CURVE,
your suspension,
AND TIRES TO PROVIDE MAXIMUM traction and HAVING
A HIGH power to weight ratio

GET THE CAR LIGHT WEIGHT ENOUGH AND YOU CAN DO AMAZING THINGS WITH MODERATE POWER LEVELS.
IF IT WEIGH'S A GREAT DEAL ,IT WILL BE MUCH HARDER ON PARTS ,REQUIRE LARGER BRAKES AND MUCH MORE POWER,TO GET THE CAR TO RUN QUICKER AND FASTER
READ THE LINKS USE THE CALCULATORS, AND think things through carefully

http://garage.grumpysperformance.co...-info-worth-reading-through.11528/#post-53210

http://garage.grumpysperformance.co...trans-choice-made-correctly.11697/#post-54833
Now back in the 1970s we used to find pintos , early novas, mustangs, darts,and vegas and swap in a 350-383 sbc, 396-454 chevy, 389-455 pontiac, 383-440 dodge or 472-500 caddy engine with a 4 speed and a bunch of fabricated parts and have a reasonable power to weight ratio.
think thru your choices! 1970s era vegas , novas,camaros,pintos,and 1964-66 mustangs are now hard to locate , that doesn,t mean theres no longer light car bodys,and the larger v8 engines are not nearly as easy to locate, youll just need to think things thru and possibly do rather extensive fabrication, to install a drive train the factory never intended you to install. on the plus side the newer ALUMINUM chevy LS series engines are available, and theres better transmissions.
http://www.carcraft.com/projectbuild/11 ... ratio.html
Gears, Mph, And Tire Height
After you've figured out how fast you want to go, you need to find the weight of the car and determine how much horsepower you'll need to accomplish your goal. The formula to estimate amount of horsepower for a terminal mph in the quarter-mile is: hp = (mph / 234)3 x weight. As an example, if your car weighs 3,000 pounds, you'll need about 500 hp to run 130 mph, and if your car weighs 4,000 pounds, you'll need about 685. This is simply a power-to-weight calculation, and experience has shown us it is a little conservative, much depends on the engines torque potential. There are a lot more factors involved in goin' fast, but this is a good place to start, and it shows why weighing less is better.

The next thing you need to do is find out where your engine will make peak horsepower and pick a rear gear that will put the engine at about 200 rpm above that number going through the traps in High gear. Here is the math: gear ratio = (rpm x tire diameter) / (mph x 336). This is closely tied to the size of the tire you are going to run, so before picking a rear gear ratio, find the largest tires that will fit under the rear. You should also note that an automatic transmission in High gear will exhibit about 5 percent slippage, so you will need to add that to equation.

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.
volumetric.gif

exhaustpressure.jpg

EXFLOWZ4.jpg

137998aa.jpg

tubsed.png

expik.png

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.
COMMON SBC INTAKE PORTS
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

USE THE CALCULATORS, YOULL, QUICKLY FIND THE LIMITATIONS
http://www.rbracing-rsr.com/runnertorquecalc.html
http://www.wallaceracing.com/chokepoint.php
http://www.wallaceracing.com/header_length.php

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
portfl3.jpg

http://garage.grumpysperformance.com/index.php?threads/the-new-215cc-vortec-heads.266/#post-75012

http://garage.grumpysperformance.com/index.php?threads/carburetor-intake-manifold-test.58/

http://garage.grumpysperformance.com/index.php?threads/holley-accelerator-pumps-cams.1790/

http://garage.grumpysperformance.com/index.php?threads/setting-up-your-fuel-system.211/

http://garage.grumpysperformance.com/index.php?threads/holley-carb-power-valves.1639/

http://garage.grumpysperformance.com/index.php?threads/cooler-denser-air.8961/

http://garage.grumpysperformance.com/index.php?threads/car-falls-flat-in-third-gear.9326/

http://garage.grumpysperformance.co...-the-holley-4150-and-4160-series-carbs.10736/

http://garage.grumpysperformance.com/index.php?threads/carb-tuning-info-and-links.109/

http://garage.grumpysperformance.com/index.php?threads/is-backpressure-hurting-your-combo.495/

http://garage.grumpysperformance.com/index.php?threads/calculating-required-exhaust-pipe-size.11552/

http://garage.grumpysperformance.com/index.php?threads/building-an-exhaust-system-for-your-car.1166/

viewtopic.php?f=52&t=5078&p=14840#p14840

viewtopic.php?f=44&t=38

viewtopic.php?f=87&t=9731

viewtopic.php?f=44&t=3733&p=30179&hilit=getting+started+hobby#p30179

http://vexer.com/automotive-tools/1-4-mile-ET-HP-MPH-calculator

http://www.wallaceracing.com/et-hp-mph.php

http://garage.grumpysperformance.co...-info-worth-reading-through.11528/#post-53210

https://robrobinette.com/et.htm

http://www.ajdesigner.com/fl_horsepower_elapsed_time/horsepower_elapsed_time.php

http://www.tuneruniversity.com/blog/2012/03/power-to-weight-ratio/
 
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Re: whats it really take to run reasonably fast in street t

logic says you need to carefully match components to produce the best results,
a few days actually thinking out your combo and taking the effort to research what components to select to carefully match the intended power levelsand rpm limitations will allways pay off in a better combo that randomly assembled parts.
one of the common problems I, but certainly not this one alone,is that I see guys fight is having an intermittent lean miss on cars that they built where they modified the engine but continued to use the stock fuel lines, fuel pump and fuel filter, it takes a certain fuel/air ratio to produce a certain power level, and at some point a fuel system designed to feed a 200hp v8 will be hopeless on a modified engine that produces well over twice that power level.
yet for some reason that fact that the oem fuel system seems to work fine at lower rpms , also seems to prevent it being suspected as a potential source or problems
what works just fine in a fuel supply system idling in your drive way on a 350-400 cubic inch engine thats common in most cars ,built for performance,to feed the needs of an engine running at 1500rpm-3000rpm is a far cry from whats required at 6500rpm under 3/4 G acceleration loads.
that brass fitting you picked up cheaply some place that feeds the 3/8" inside diam. hose that has the 1/4" passage thru it , that allows a fuel pump rated at lets say 130gph to pump 70gph, won,t seem restrictive until the cars under full acceleration in top gear
with out testing theres now way to know if that particular application has a potential problem, but keep in mind that the carbs fuel bowls hold a certain amount of fuel reserve and the fuel pump is designed to feed fuel at a set rate or volume and pressure, usually at 5.5psi-6 psi measured at the carb fuel supply inlet port.
its entirely possible for your cars fuel system to be able to supply fuel at a rate,pressure and volume at lower rpms that keeps the carbs fuel bowls filled , but at some point the engines needs exceed the fuel supplied by the fuel entering the carbs inlet port, and the difference is being temporarily maintained by the volume in the fuel bowls, this is common, and in marginal systems tends to mask a potential problem that will rarely show itself due to the minimal time duration the engine is subjected to the conditions over taxing the fuel delivery systems potential as few of us do more than occasionally race for a few gear changes with friends on back rural roads, but if the car was ever pushed for more than 12-15 seconds at wide open throttle the condition would become far more obvious

I think youll find Use of 1/4" and 5/16"fittings will effectively reduce the fuel pumps max flow rate, on any performance application significantly, Id suggest 3/8" INSIDE DIAM. lines and matched fittings at a minimum, I think youll find a great deal of related info in the links

viewtopic.php?f=55&t=211

viewtopic.php?f=55&t=1939

viewtopic.php?f=55&t=635

viewtopic.php?f=55&t=211&p=275&hilit=fuel+filter+drain#p275

viewtopic.php?f=55&t=5365&p=16067&hilit=+manual+fuel+pump#p16067

a few related threads that might help you build a better car

http://garage.grumpysperformance.co...-that-makes-many-of-the-cars-desirable.11244/

http://garage.grumpysperformance.co...-of-grand-sport-corvette-hash-marks-etc.6849/

http://garage.grumpysperformance.co...e-to-run-reasonably-fast-in-street-trim.3404/

http://garage.grumpysperformance.co...ket-race-not-transportation.14229/#post-72589

http://garage.grumpysperformance.co...-calculators-and-basic-math.10705/#post-72061

http://garage.grumpysperformance.co...ive-train-to-the-engine-combo.741/#post-70350

http://garage.grumpysperformance.co...ing-parts-and-a-logical-plan.7722/#post-68651

http://garage.grumpysperformance.co...ing-a-cobra-replica-kit-car.10356/#post-48297

http://garage.grumpysperformance.co...ting-started-in-the-car-hobby.339/#post-60187

http://garage.grumpysperformance.co...gine-to-match-the-cam-specs.11764/#post-58001

http://garage.grumpysperformance.co...y-in-building-a-good-engine.11682/#post-54682

http://garage.grumpysperformance.co...-info-worth-reading-through.11528/#post-53210

http://garage.grumpysperformance.co...acing-info-lots-of-good-stuff.373/#post-52133
 
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Re: whats it really take to run reasonably fast in street t

5/8" ID Is minimum for serious HP.
THE HP PHIL & ME DREAM OF.....3/4" ID FUEL LINE SYSTEM.
1/2" WORKS TO 550-600 HP NO FLOW RESTRICTIONS ANYWHERE.
 
Re: whats it really take to run reasonably fast in street t

it depends alot on your pump brian, that fairmont i posted earlier makes 721 to the tire on 3/8 lines however my buddies 440" nitrous powered rx7 was running out of 5/8" line at 780hp. now i doubt the difference between 3/8 and 5/8 inch is 60 darn ponies so theres lots of factors to consider... grumpy had a great thread somewhere on here about inside diameter of fittings, particularly angled fittings that i never even considered before and found very eye opening.
 
http://www.atlasmusclecars.com/amc/cheetah-502-kit-car/210/
Here we have a very nice 1965 BTM Cheetah Continuation Roadster, equipped with a Chevy 502 big block V8, speed transmission, 4 barrell carburetor, custom ceramic coated headers, rack and pinion steering, manual vented four wheel disc brakes, 4130 Chrome Moly tubing frame, Fully adjustable independant suspension, four wheel coil over shocks, tubular wishbone and trailing arms, Corvette spindle, bearings and independent rear end. Body is hand laid fiberglass with 6.0 oz. cloth inside finish and inner door panels. Complete weight of this car is 1,700lbs, the wheel base is 90 inches long and 59 inches wide. This is a really cool car for the avid collector that loves the mid 60s race cars or someone that just wants something different to drive to the shows. Killer car with killer looks. $34,000.00

Bit of History on this car:

The Cheetah is Born

In the 60s, it was Chevrolet idea - and Bill Thomas dream - to create a car that would challenge the Cobra. The result? The awe-inspiring Cheetah, born of vision and guts and a commitment to build a car that would shatter track records along with the Cobras dominance. With storied race-car builders Don Edmunds and Don Borth, Bill Thomas built a car that in turn built a new story of speed. 185 mph at RoadAmerica. 215 mph at Daytona.

Despite the small staff producing the car, the Cheetah, boasting shockingly good looks and unheard-of performance, developed a fanatical following. It did not just turn heads at tracks: the street version brought envy to every neighborhood it called home. But sadly, it was not meant to be: Chevy pulled its support and, in a twist of unfriendly fate, fire destroyed the Cheetah factory. The dream ended, but the haunting question remained: What might have been?

heres an example of what might be built from a kit car that would kick butt!
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new13111911656.jpg


new13111921181.jpg

tumblr_omi5br9uAg1ttxfeno1_1280.jpg
 
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So really it just takes allot of $$$$$ just kidding but it helps. lol I really like the race car kit cars allot and would really love to build my own purpose built track car some day. Right now not feasible but who knows down the road.
 
unfortunately for most of us, much of this hobby revolves around a constant flow of cash!
I think most of us would love too have an extra $1500-$2000 a month dedicated for the purchase of tools and car parts!
but for most of us of course thats never going to happen!
 
personally I think the AC cobra looks MUCH better than the cheeta,
and that blue McClaren, can-am car looks better than either of those,
not as practical, for a street hotrod,
no doubt!
but without any doubt faster and better handling than either also!
maybe its just me, but seeing a car that easily exceeds 200 mph and can take a a S turn that your daily driver could barely do 40 mph through,
at 80 mph without a hiccup,
and out accelerate a 10 second 1/4 mile car easily,
and pull well over 1 G braking and in the turns,
is impressive as it gets, and weighting under 2000 labs and having a 700 -800 hp plus,
BBC in many of them certainly does not hurt my feelings either

cana3.jpg


canamkl2.jpg

cana5.jpg

chap3.jpg

chap5.jpg

LOOSELY RELATED
(BUT NEAT CARS)


http://garage.grumpysperformance.co...g-custom-car-body-suppliers.11629/#post-54275

http://garage.grumpysperformance.co...n-am-car-series-was-dropped.11411/#post-52320

http://garage.grumpysperformance.com/index.php?threads/source-for-muscle-car-bodys.11722/#post-68550
 
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I know it was just a TV car, but I kinda liked the Coyote from Hardcastle & McCormick.
Does anyone know what that had for an engine?

Coyote_024.JPG

coyote-x-tv-car-10014.jpg
 
Coyote info:

Owner

Dave D.
Location USA
email wildhorses_3000@yahoo.com
Web Page -
Year -
Car Montage
Color Coyote Red
Builder George Barris
Chassis Type VW
Chassis Number -
Engine Make VW
Displacement 2387 cc
Transmission/Transaxle VW
HP 220-280 (Dyno test results coming)
Front Suspension VW modified
Rear Suspension custom
Steering manual
Interior vinyl
Notes This is the origional Coyote for the Hardcastle & McCormick TV show. Purchased from Code1 Eric S. It comes with documentation and origional bill of sale from Hollywood. It is currently in the process of a frame off restoration. Due to the fact that it was a Hollywood car, it
 
If any of you are interested a friend is selling his Kellison Kit car he's owned a long time, probably over 30 years. It'll be pretty cheap because it's gotta go NOW! Resembles the original GT 40 type car. Has recently rebuilt Corvair engine. Body needs some work but he needs the garage space and is going to devote time and money to finish his Factory Five GTM. He's pulling it out of storage tomorrow so I'll get pics soon.
 
yeah!
posted clear pictures, location, more details and price would be critical
 
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