Me and my friend were talking about cars and I said something about what I was going to do this winter, which is replace my 8.6:1 pistons with 10.5:1 pistons. Im going to be boosting at 15psi right now. He says he learned in school that you cant do this because there wont be enough room in the cylinders w/ that compression for turbo... Me, I have no schooling, I just know more then average... What I think is, Im going to still be able to boost 15 psi its just going to be packed into the cylinders tighter. (I know that you run higher risks with higher compression) Some body set one of us, or both of us straight please.

High compression and turbo is possible form what has been said here, it's just that you push yourself that much closer to the possiblity of detonating. You can use the Search function and check the board, but the short answer is that it *is* possible, just a bitch of a tuning PITA.

-Corey

argh!!!!!!!!! not this question again (trips own hair out off).
-------jezreel

Yeah basically the higher compression has less room for error, but a hell of a throttle response if you tune it right... i want to try this too...

Well this is what I want my setup to be: 12:1 pistons ceramic coated with crane #18 cams. I well use the rods I am already using which are from crower. I well hopefully find some over sized valves that are nice and get all my head work done. I want to be running at 15 psi of boost. Ive heard that the cams arnt the best for turbo but I dont know for sure. This cars is not a daily driver... I take it out for racing only. It well see streets, just not a lot. Well this setup be good... Or better yet. If you had cash flow what would you do... Remember that detenation does not scare me. If I break somthing it well just give me a reason to make it stronger.

a good setup would be 11:1 with avgas

u will need a standalone to pull this off properly...

run about 25psi or so on 11:1 with a sheetmetal intake all moly coated and ceramic coated motor fully built head with moly coated cams and race port job, ferrea valves,

and with the proper supporting mods the car should make alot of power


(the phat ridz yellow neon last i heard was running 11:1 with almost 30# of boost and a 250shot...)

Bill

ok I think I'm qualified to give a little review about hicomp. I rebuilt my engine with JE 10.5:1 pistons and all I can say is wow. You have room in the the chamber for the pistons so don't worry about that. I get like 250-270 compression and wow the boost builds up fast the boost needle gets up there pretty fast. The lag points are roughly the same but man when you get on the throttle the boost creeps up quickly hard to explain. Also since it spools so fast you boost more and faster at partial throttle which can be problem -_- you can lean it out at partial throttle which I've done. but at WOT its mega lean still so I need a SAFC bad now.

another thing about hicomp is that you MUST put supreme/high octane in it. I tried to put plus 89 octane in it one time because I was short on cash and it ran like shit. before I got away with it on my stock pistons but hicomp is a no go with lower octane.

I just took my car to hiway9 a nice mountain with lotsa twisties. Its the usual place I like to do spirited driving. Well I'll tell you this, that was the first time I took my car there after the rebuild and it tore that mountain a new one. the quick boost was awesome cuz it could pull me up the hill no problem on some of the straights I managed to get to 80 and the straighter parts 105 the most I've probably ever gone is 90 up there. I pulled some good lateral Gs on the turn too ^_^

Also my brakes faded and were glowing red hot when I hit the bottom. I have the 3000GT DPCs and performance rotors but stock pads. and I've taken this thing to a race course, drifting, consecutive stop light drags, and previous runs on hiway9 and they performed well. Not that night I maxed out the brakes again, so time to upgrade again :P

Well I have clearence issues with 12:1? or should I consider somthing more like 11.3:1 Also how do I get a piston with compression ratio of 12:1. Do I have to speical order it.

unless your gonna run standalone and either avgas 100% of the time or methonal 12:1 sould not be a good idea...


Bill

It's cool that you're not afraid of detonation and all that, but wouldn't you like to make a complete pass before you blow something up? Hehe. You've got a LOT of work ahead of you if you want to make that set up work.

Motofool's the man, and if he says 12.5 is gonna be a bitch - you better believe it's gonna be a bitch. }(

12:1 are you mad?! I heard the highest you should go with boost is 10.5 but even for just NA 12:1 is already not streetable. Your call though just make sure you got all that rocket fuel ready ^_^

I got 2 barrels of super 16, but im going to try like 11.x