LS2 compression [Archive] - SmokinVette.com Forums

: LS2 compression


747flyboy
01-02-2010, 04:46 AM
I was wondering those that have modified their LS2 motor, what compression are you running at? Would you please list your mods also. Thanks!

CarlRx7
01-02-2010, 01:12 PM
supercharged runing 9.1 lbs of boost, stock compression

PCHS Racing Engines
01-05-2010, 12:29 PM
If you are running Blown, Super Charger, Turbos you want 9:1 Compression. But if you are Running Normally Aspirated You can go to 11:1 but not if you are Running 11:1 93 Octaine or Better

powerlabs
01-05-2010, 05:54 PM
With enough cam duration you can run 12:1 and higher. I know of one pump gas LS2 running 12:1 compression with a big cam. It makes just shy of 500RWHP. You have to remember that because of valve overlap the static compression number is not all that meaningful; dynamic compression is what the engine is really seeing.

On a supercharged engine you want less of course. But then it becomes a trade off between how much boost you can run (and thus how much power it'll make) and how much throttle response, fuel economy, low end torque and off boost power it'll have. THe stock 10.9:1 compression will allow quite a bit of boost; mine ran 11PSI for 30K miles, others will take it as high as 14 or 16PSI with methanol injection.
On my rebuild I am shooting for circa 9.8:1 compression so I can make around 700rear wheel horsepower, which will be 14PSI or so through the motor with a ZR1 cam.

Ragtop 99
01-06-2010, 05:26 AM
If you are running Blown, Super Charger, Turbos you want 9:1 Compression. But if you are Running Normally Aspirated You can go to 11:1 but not if you are Running 11:1 93 Octaine or Better

IMO, to drop to 9:1 requires a max effort build beyond most street cars. A lot of reliable 600 RWHP builds at stock compression (10.9:1) and dropping to around 10:1 should handle 800 RWHP without issue.