ok well i'm buildin me a 2.4 dual over head cam turbo project and i was wondering what compression ratio you would recomend on runnign i wanna ruun HIGH boost so yea what ratio?

How well can you tune?

lower than stock....9.0:1 maybe

Quote:

How well can you tune?

Thats a good point,

Also you need to think if you want to run pump gas.

I bought 9:1 for my eco.




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CARCUSTOMS.NET, THE BEST SERVICE ON THE ORG!!!

http://www.goodvibesracing.com/Compression%20Ratio.htm

That should give you the numbers you need.


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'96 Cavalier Good ol' Pushrod 2.2
-24X,000 miles on factory build
-Some oil loss between changes, me thinks it be rings.

Depends on what your tuning with and what your building the car for. We need more info.




- 97 Z24 Racecar work in progress
- 04 WRX STi
ATR Crew Member

i'm building it for a fun car the car i go get in to go out and race people only... so it's still gotta be streetable so i can drive around time but when i drop the hammer i want to FLY

So this is going to be a mostly street driven car. So im assuming your going to be running basic 91-93 high octane. I would build the motor with higher compression with lower boost levels. Like a 10 or 10.5:1. A setup like that will give you some nice TQ# low in the rpm range with quick spool up. Which is what your going to be looking for on the street. If it was more of a track car I would lower the compression a bit and up the boost for a higher up in the rpm range power band. But when it comes down to it its all going to depend on your tuning. That will make or break any setup.




- 97 Z24 Racecar work in progress
- 04 WRX STi
ATR Crew Member

I'm with Atomic on that one, it's what I'm building right now 10.2:1 static cr with 10 - 15# of intercooled water/meth injected turbo boost for daily driving.


2000 Z24 5spd header & catback for now.

If you want the low rpm hp and tq just get a smaller turbine turbo........ Id run 9:1 compression just because its goin to be a street car and you probably want the car to last for awhile right? that 1 extra compression is goin to give you what 15 hp tops and maybe 15tq im not knocking the higher compression ratio but thats just what I think

Running higher compression is not about getting that extra 15 hp and tq. Its more about getting a high flat torque curve. If you want another 15 hp just turn the boost up another psi or two. You could do that with a smaller turbo as well but your going to be limiting your maximum power output and raising IAT temps at the same time.




- 97 Z24 Racecar work in progress
- 04 WRX STi
ATR Crew Member