what should i do????
what should i do???? ok i picked up a package deal on alot of stuff. i got a comp cam that is .523/.528 Dur@.050: 214/218, 1.8 crane gold roller rockers, lq4 heads with port work done to them. i got an ls6 intake with a morgan mortorsports p&p throttle body. flp long tubes and y pipe. do you think that cam is big enough???? i would like to have a 400 hp daily driver. plus a 200 shot just for a little more fun lol. should i go with a bigger cam??? should i have the heads milled??? 
The lq4 6.ol heads are going to hurt you on power N/a. The truck heads have larger combustion chamber than an 346 stock for stock. 6.0 L engines have a larger piston 4.00'' bore so they make up for it . Stock combustion chamber 346ci ls1 is 65cc. I believe the lq4's are around 70cc which will drop your compression from 10:1 stock to around the 9.5:1 range . Not a good route for all motor N/A combos. With them ported the chamber may be even larger. I would have them cc 'ed so you can find out before you install . On the other hand they are optimal if you plan on a supercharger/turbo or turbos in the future . Larger chamber allows more above atmospheric pressure { 2-3more psi on a standard intercooled 8 pound of boost kit on stock pistons} to be ingested without detonation /knock because of the lower compression when tuned . A bigger cam is not always better most over cam and are left with poor lowend pickup.
More compression is needed and a cam with proper valve events is crucial to power gain .
More compression is needed and a cam with proper valve events is crucial to power gain .
Last edited by cws T/A; Aug 17, 2006 at 05:36 PM.
The lq4 heads have a 71 cc chamber volume which will give you a 9.4:1 compression ratio. Are they milled already? If not mill them.
The cam is on the small side, but it's bigger than the stock cam. The 1.8 rocker arms will help on the lift too.
I wouldn't run a 200 shot on a stock bottom end.
I think you will see real close to 400 hp to the rear wheels with that setup.
The cam is on the small side, but it's bigger than the stock cam. The 1.8 rocker arms will help on the lift too.
I wouldn't run a 200 shot on a stock bottom end.
I think you will see real close to 400 hp to the rear wheels with that setup.
