wats the cr of a new vortecmax engine isnt it 9.6 cr

 

http://www.gmhightechperformance.com.../photo_02.html

 

If a LQ4 shortblock w/317's is 9.40, then your Patriots Stage ll's with 72cc chambers drops you to 9.31. The 70cc L92's bump you up to 9.50.

http://www.kb-silvolite.com/calc.php?action=comp

Swapping to L92's is a lot of work/$$$$ for the minimal increase you'll see over your Patriot heads. You have to pick up a TB or L76 intake with a 90mm throttle body and a Dr X adapter. You'll be hitting $1400 + you'll need a new cam to see any real benefit. The L92's have a poor intake to exhaust flow ratio. The intake rocks but the exhaust sucks. That's why the the L92 cams have such a huge duration split between the intake and exhaust. IMO, keep the Patriots and pulley down or get a custom grind cam. You'll probably make more power than the L92's and not have to worry about the thin deck.

This is a link to L92 with a LS6 style intake swap. Pretty cool but $$$$.

https://www.performancetrucks.net/fo...hlight=l92%27s

Rick

 

the thng is i think i already have a cam thats for l92 cuz pg spec me one and i hink its the same one here




LS/R Rectangular Port 3-Bolt Cams (For All Out Power Only, 5.7L - 6.2L)


Part # Product Price My Cart Wish List
63-54-469-11 Comp Cams Hydraulic Roller 231 / 247 .617/.624 113 LSA, Very wide power range and excellent midrange torque for LS engines with rectangular port cylinder heads. RPM range from 2000 to 7000 New! $384.99
Buy

 

A friend and I are getting ready to build a 6.0/408 with L92 heads and a Kenne Bell 2.8 blower for my truck this summer. Starting to get all the parts together and getting the block into the machine shop to get the machine work done.

 

I'm running a LS2 with L92 heads and TVS2300. 10.5-1 CR. Runs great......
Mine was a Max and the stock CR was 9.6

 

What head gasket should I go with in between the 408 and the L92 heads?

 

The L-92s are great heads and flow wonderfully for a FI application. They do require special pistons and rockers. We just finished a 413 project with a 6.0block and the engine rocked. Torque is unbelievable over the power band, averaged 730 ft/lbs at the fly on only 9lbs of boost. Here is the dyno sheet.

 

Hey fish what did you use for a blower?

 

700+ @ 2400 RPMs . . . . got any more details on the build ?