how do i make lower compression

[TheFlashDSM]

my engine has, a garrette gt35r full front mount kit no ac or power steering i have 750cc injectors on a stock 95 4g63 i recently had the head gasket replaced with a new metal one also arp head studs put in how can i run lower compression in my engine and dont mind riping it apart project car

 

[LiquidX]

Put in lower compression ratio pistons and a thicker head gasket.

 

[TheFlashDSM]

what kind of pistons and gasket

 

[RadDsm]

Why do you want lower compression? 8.5 isn't really high.

 

[LiquidX]

What is your current CR, why do you want a lower CR, and what are you plan ing on doing with the car?

 

[TheFlashDSM]

im looking to make some power for the track but im still a newbe with this shit but the stock cr is 8.5? and also i have a big turbo and lookin to make power without blowin my engine i herd lower compression is better with boost

so how am i suppose to reach lower cr and whats a good cr to run

 

[krackit]

word on the street is you don't wanna go much lower than 8.5....otherwise you lose power when turbo isn't running...it also depends on the gas you're running. but i think people on here go 8.5-9.6...some daring go over 10.

 

[SpawnedX]

Word on the street is that before you start messing with this stuff, you clearly need to read some more about how engines and turbos work in relationship to compression. No offense, but just by the question you asked, you aren't ready for much more than bolt-ons.

 

[krackit]

Word on the street is that before you start messing with this stuff, you clearly need to read some more about how engines and turbos work in relationship to compression. No offense, but just by the question you asked, you aren't ready for much more than bolt-ons.

i agree with that...not knowing that CR is based on your piston and gasket...do some research on what CR actually is....but basically changing your CR means swapping out pistons...which at that point, you might as well do a rebuild if the block is stock.

 

[Hitmachine101]

lower compression mean Lower Compression pistons. all this will do for you will make going higher in boost easier to tune aka less possiblity of knock. but this also means less hsp unless you run a crap ton of boost. like the other guy said build the motor while your in there

some people go with higher compression pistons and smaller turbos to make it more of a street car that could reach 11s with a good tune and a 16g

but thats much harder to tune

8.5 stock compression ratio is plenty low enough for large boost, personally id just build the bottom end and go for it

youll have to rip it apart anyways to lower the compression, so do some reading and save up for that bottom end

 

[Sam@RRE]

Word on the street is octane is the biggest limiting factor. You can go stupid low CR's to prevent knock at higher boost levels, but it wont net any power gains due to the low compression itself. The other option is running real fuel with lead in it, or alcohol. Knock prevented.
Or option B, lower your compression without wrenching on anything, disable knock sensor, 25+ psi of boost, 14:1 AFR and 23* of timing. It will lower your compression ratio for sure.....

 

[chaggard27]

Word on the street is octane is the biggest limiting factor. You can go stupid low CR's to prevent knock at higher boost levels, but it wont net any power gains due to the low compression itself. The other option is running real fuel with lead in it, or alcohol. Knock prevented.
Or option B, lower your compression without wrenching on anything, disable knock sensor, 25+ psi of boost, 14:1 AFR and 23* of timing. It will lower your compression ratio for sure.....

That was my thoughts put into words I was going to tell him to get a hallman, crank it all the way up, and then floor it with stock injectors until there is smoke and you will then have a lower compression motor on your hands

 

[crazyboy81]

The key to bad advice is to understand what NOT to do haha

 

[SpawnedX]

Word on the street is octane is the biggest limiting factor. You can go stupid low CR's to prevent knock at higher boost levels, but it wont net any power gains due to the low compression itself. The other option is running real fuel with lead in it, or alcohol. Knock prevented.
Or option B, lower your compression without wrenching on anything, disable knock sensor, 25+ psi of boost, 14:1 AFR and 23* of timing. It will lower your compression ratio for sure.....

This post may or may not have made my pants a little tight. Why can't you guys move to the east coast.

 

[Absit]

mountainbike91
To summarize, stop working on your car and start reading a book.