89lx-ls1

iTrader: (23)

I want to put a procharger on my motor but it is 11.7 compression. Anyone have any opinons of doing this? My buddys M3 is 11.6 com. and he has 7 lbs on his and runs great on pump gas(i know its not an ls2)but what do you guys think. I put down 475 hp and 575 tq the other day on the dyno also just alittle more info. All parts needed to know about are in my sig.

Thanks in advance
Jon

EPP

iTrader: (22)

I'll bet you could get away with 6 to 7 lbs of boost, with the camshaft that you have and the fact that your car is really light. Bob

89lx-ls1

iTrader: (23)

any more opinions on this setup

ViperX

Buddy with same setup runs 8psi hasn't gone boom yet!

Wet 1

iTrader: (4)

I also believe 7 lbs should not be an issue. I wouldn't even worry to much about 10 lbs. on 93 octane while spraying a good shot of meth.

89lx-ls1

iTrader: (23)

I would def. run race gas with any more than 6 lbs. But thats good to know.

89lx-ls1

iTrader: (23)

Any more thoughts? I saw another thread sayinga guy could only run 5#s with 10.75 to 1 compression

Got Me SOM

iTrader: (2)

well that huge *** cam will bleed off some of the compression. Can I ask why you are running that cam? Were you planning on going a different route and now you want to put f/i on? You may not be able to run as much timing as you should with that setup.

If I were you, I'd change the compression and get a milder cam you don't need that.

If you decide to keep it, run some good gas, even though your car is light and the load won't be as much that is not boost friendly compression.

If it were me I'd change your compression and cam, you simply don't need that for forced induction.

89lx-ls1

iTrader: (23)

I WASNT PLANNING ON BOOSTING THIS MOTOR BUT IT DOESN'T SOUND LIKE A BAD IDEA AND IT IS A TORQUE MONSTER THE WAY IT IS BUILT AND I LOVE THE CAM. WHY ARE THESE BMWS ABLE TO RUN UPWARDS OF 10 LBS OF BOOST WITH 11.6 COMPRESSION? AND ASSUMING THAT f/i MEANS FUEL INJECTION, NO I DONT WANT TO PUT IT ON THERE I STILL AM GOIN TO RUN THE CARB SETUP. RIGHT NOW I AM RUNNING 29 DEGREES OF TIMING WITH 93 OCTANE ON THE STREET. I DRIVE IT EVERYDAY GETTING AROUND 15-16 MPG.

Urban Legend

iTrader: (5)

Gotta love the all caps!

89lx-ls1

iTrader: (23)

I Am On The Computer At Work And That Is The Way That All Of Our Tickets Are Written So I Leave It Alone And Dont Mess With It

Urban Legend

iTrader: (5)

I'm just messing with you man.

Camaro99SS

iTrader: (4)

It's all about cylinder pressure. A 11.7:1 compression motor doesn't need as much boost to create the same amount of cylinder pressure as a 8.5:1 motor because the combustion chambers are smaller. So a 8.5:1 motor that's getting 20psi will have the same cylinder pressure as the 11.7:1 motor with, say 10psi. Assuming all else is equal, more cylinder pressure = more power. But to keep things in check, you must have enough fuel getting in to keep the combustion temps low enough not to fry piston rings. And, too much timing advance will heat things up in there as well.

This is a pretty simple way of looking at it, but the same principle applies to any engine really.

Jason

89lx-ls1

iTrader: (23)

Thanks for the info. but how much should i be able to run? I figure i could put 6 psi and run some meth. and stay on pump gas?

Paulz2820

iTrader: (1)

your playing with fire son and it hurts to get burned. do it right the first time.

Camaro99SS

iTrader: (4)

I'd keep it at 5 or 6psi and you should be fine. But you're really gonna have to keep a FAT tune on it, about 11.5/1 or a little richer past 4000 and don't run alot of timing. Personally, unless you can come across a used one for really cheap, the hp/money spent won't be that great because you'll have to stay conservative on boost and the tune. However, it can be done. You'll just have to be **** about tuning. A dyno tune in your case is a must, no exceptions.

Jason