The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post

JJAB · 09-07-2012, 02:03 PM

Guys, I am about to build a 408 stroker motor out of a stock LQ4 motor. In my experience of putting hotrod motors in EFI vehicles, there sometimes is a problem of making the computer(ECU,PCM) and the compression ratio work together and be a "happy couple". Would you knowledgable LS guys here on the board reccommend a compression ration to stay away from? \

I know a lot depends on what I expect out the motor and what I am going to do with the vehicle that the motor is going in so here is the basics. Its going in a SWB truck and I would like to achieve 450 RWHP. So that being said I am estimating that the crank HP needs to be in the 575 to 600HP range. Opinions please??

09-07-2012, 02:03 PM	#1
JJAB Registered User Join Date: Sep 2010 Location: Waco,Texas Posts: 143	Compression Ratio Guys, I am about to build a 408 stroker motor out of a stock LQ4 motor. In my experience of putting hotrod motors in EFI vehicles, there sometimes is a problem of making the computer(ECU,PCM) and the compression ratio work together and be a "happy couple". Would you knowledgable LS guys here on the board reccommend a compression ration to stay away from? \ I know a lot depends on what I expect out the motor and what I am going to do with the vehicle that the motor is going in so here is the basics. Its going in a SWB truck and I would like to achieve 450 RWHP. So that being said I am estimating that the crank HP needs to be in the 575 to 600HP range. Opinions please??