Do you have to keep the compression down when building a turbo or supercharged motor?
Or just on the SUper, or both?
And how high could you go on a 350 with how much boost
With rebuilt motor of course
thanx 4 yor time
jmp

 

Its best to keep the compression under 9:1 with ANY forced induction engine. As for the amount of boost... it is a according to how the engine is built ex. if you build an engine with hypertetic pistons and a cast crank, then pumop 20 p.s.i. into is, chances are that its gonna "hand grenade". An engine needs to be built strong enough to handle all that extra boost its getting. Theres also the issue of timing retard & intercooling, but i wont really get into it

If you really neet to talk to someone, i suggest talkin to Guido... he knows his stuff!

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92' White Trans Am Convertible, 305 TPI, 5 spd. 2:73's, Edelbrock TES, Accell 8.8's, Hypertech Stage II, TPIS Air Foil, Ported Plenum, K&N TB Cone Filter, AFPR, & A Little Bit Of Attitude!
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"GUYS, WE NEED TO FIND A MUSTANG TO RACE... THERES ONE! HOLY SH*T SHES HOT! SHES NOT GONNA GO... NAH... HOLY SH*T SHES GOIN!"

 

You can have any compression ratio you want but the more you have the less boost you can run.

Pete

 

The amount of boost and/or compression ratio
you can run is tied to the available octane gas. If you use 114 octane race gas you can run a lot more boost and/or compression.
Generally speaking if you run 92 octane street gas: use a compression ratio of 8.5:1 or less and around 6 to 10 lbs of boost.
A little ignition retard while under boost will help you run a little more boost but not much. Make sure the motor is getting all the fuel it wants while under boost. And run a cooler spark plug. (2-4 sizes) Intercooling and/or water-methanol injection
will allow you to run more boost/compression
with less ignition retard, for the same octane fuel. Detonation (pinging, knock) must be avoided at all cost or the motor will soon fail.

 

You can run any compression ratio you want, but the higher the compression the higher the octane fuel will have to be, so.. I believe most turbo/super setups keep compression around 8 or so to keep it using street gas.

The amount of horsepower you get out of an engine is a direct result of how much money you're willing to spend.

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89 iroc-z 305 tbi
k&n filtercharger, open element air filter. nuffin' else