N8Miller

hello, my cousin is gonna have his carb car dyno tuned in the spring. i know on computr cars, you can play with fuel pressure, timing and all that good stuff. now, while you can adjust all those for a carb car, is it worth it without having the compter and custom chip?

anyway.....can somebody post dyno results and HP gains from a dyno tune?
thanks

Apeiron

I never thought I'd see the day when fuel-injected cars were considered more "tuneable" than carbureted ones.

paul_huryk

The answer is absolutely yes. Carb cars by nature are a lot harder to tune - not the adjustment process (that is very easy), but the getting it on target part of tuning. I don't need to tell anyone that a Holley is the hardest to tune perfectly - but also has the most adjustment capability. Timing needs to be maxed out (typically) and the timing curve needs to come in at the right RPM and the right amount of initial timing needs to be set. It is easy to do with the springs and wights for a HEI (if you have one).

I don't have an exact figure on how much HP gain a typical half-azz tuned carb car can gain from dyno tuning, but I figure 20 to 75hp depending on how bad the car is tuned to begin with.

For example, I never took my camaro to be dyno tuned - I used an A/F meter instead. By tuning the carb (its a CCC Q-Jet), timing, and raising the coolant temperature (from 160 to 200), the car gained 35hp (355 to 390). I think since the car is very close a dyno tune would maybe give 10 more hp, but who nows until u try.

N8Miller

thanks for the responses guys.
the reason that i think that FI cars are easier is, well, i won one. not to sound arrogant, but i think that its more "plug and play" friendly then carb cars. dont get me wrong, for the track, i think carb is the way to go.

The guy on the phone told me for my mustang, he would probably get about 30hp to the wheels. now, i dont know how much with the camaro, but im expecting similar #s for the outragous prices they demand

but none the less, were gonna do it on the same day and see who has more power-----we got $50 to the winner .....sorry NevinKez, but im gonna take your money

Apeiron

On an F.I. car though, what have you really got to play with besides fuel pressure (if you have an AFPR) and base timing? Anything else and you're messing with computer, which a typical dyno shop isn't likely to do. On distributorless F.I. systems you can't even touch the timing without going into the computer.

Even the simplest carburetor though has more than enough range of adjustment through set screws and interchangeable parts to keep you frustrated for months. Add to that the possibilities you get from recurving the distributor and modifying the carburetor and you've got years of play time.

SilverTA

Speaking of carbs, I have a carb question. I have an '87 305 with a 4bbl. I'm told it needs to be replaced. The original was a Rochester Quadrajet. Edelbrock bought them out, but Edelbrock says they don't have a replacement carb for this car because it is a "computer controlled" carb. Edelbrock says I have to rebuild the original, and my mechanic says it's shot.
What to do? Does anyone know what kind of carb will work, or if not, how doable and affordable is a TPI retrofit?
thanks!

Rustydawg

How much is the dyno session going to cost?

I would go for it, bring all the tuning parts for your carb that you may need and different springs, weights etc for the distributor.

I'd be shocked if you didn't leave with a worthwhile improvement in power.

And you will learn a whole bunch about what your combo wants to make more torque. Well worth it, I say - even if the afternoon cost a couple hundred bucks.

Apeiron

I'd try rebuilding the carb first, even if it doesn't work yuo're only out the cost of a carb kit.

N8Miller

i was told the same thing for my 85 TA. i wanted a better one, but the "computer controlled" versioin is non replaceable...sorry


anyway, a dyno session is like 100/hour. they supply all the gauges that your gonna need excpect for a FPR.

heavy_chevy29

were do you go to have this done. do you just tell them to dyno tune your carb and they'll know what you mean. my carb could probably stand a tuning.

N8Miller

yep. basicly, i found a dyno shop in my relative area (about 2 hours away is the closest one ), so i called them, told them what i had done, what i needed done, and got a basic price. they said it would be $300-500. it all depends on how close your tuning ability really is compaired to the actual dyno.

87Formula391S/C

iTrader: (1)

SilverTA

i did the carb to TPI swap,if you do it buy a doner car or the best way to go is a painless stand alone wireing system its a lot of work we got over 200 hrs in the swich so far..an were still chaseing bugs ..lol

i bought a wrecked doner car for 500 bucks...

Sammy

SilverTA

Thanks guys. I guess I'll go for a rebuild or a new Quadrajet and bypass the Check engine light. That will give me an excuse to put some headers and a custome exhaust on...after I generate some more spending $$

johnsjj2

I know the only place around here does a dyno tune with a chassis dyno runs $175. It is not a brand new unit, but they are like a small Lingenfelter without all the R&D stuff so they make a lot of money in other areas to offset the cost.

86ZZ4

Damn, this sure dates au older guys There is tons of HP in a properly tuned carb car.My AMX is a good example..390 4 speed car,completly stock long block,just a Torker ,830 cfm Holley/Proform carb,headers and MSD ign..and lots of tuning!!
M?T sportman Pros and 4:11 rear , funtional ram air glass hood.and some weight reduction.12.94@102.3. on a 1.84 60 ft.MPH was low due to running outa cam .car sounds like a farm truck with open headers.I believe 1/8 was 8.3X@ 84.