SIR

What are your guys opinions on porting out ls1 heads OVER 315cfm @.500. I am looking to really hog them out from ARE to be used in a 422 running a large nitrous shot. The cam is expected to be around a 245/253ish 114 with a .620 or so lift. Primary use would be track. How far do you think the ls1 heads can be ported before the laws of diminishing returs kicks in??? Can we go 330+cfm @.500?

anybody know the intake runner cc??
Also using possibly the new ls1 intakes (ie, Sypyder, weinad ls1 and the like) to maximize a large amount of breathing.I would think with pig ported heads and that intake I should be able to push out the maxve before it collapses.

SpeedDemon

There is no need to open them up that big to make them flow 330. It takes a lot of finesse to do it, but in the right hands, 330 is just the beginning! It all depends on how much money you have. <img src="images/icons/smile.gif" border="0">

AREGHOSTZEE

The stock portvolume on the ls1 head is 202 cc and the ls6 about 110cc on the intake port. 330 CFM at .500 lift won't be to easy and will be a seriouse set of heads, 300cfm @.500 lift is pretty dam good for that fact.

SpeedDemon is right in that these would tend to be a very expensive set of heads as the labour would be high. We are almost ready to release our "R" series heads to the public(and no not the C5-R heads! as someone already mentioned). They are an extreamly agressive ls1/ls6/lq9 head that can used with the factory intake as well as one set that requires a custome intake/valvetrain to match.

SIR

Hmmm sounds good Nick. I cannot keep up with you guys!! hah

Could you give some specs on your new "R" series setup? How large of a move are they from your stg2 heads?

I am looking for something radical, something EXTREAMLY aggressive. So far I have a base of 422 and roller cam. This will be a track car. I have also been talking to someone about your custom "head gaskets" that you use on those large nitrous shots. I was also informed of the expensive and think it would be worth it for the motor I have planned.

Is your custom intake a spyder et al derivative? I am waiting for CEndres to test the spyder intake out to see if it performs.

thanks for your time.

AREGHOSTZEE

There will be 2 versions of the "R" series heads that we planned, one will still use the factory intake manifold style and the other a custom intake. I hope to be testing manifolds with Chris E soon and share the results, the first set of heads are close to being ready and will run on the factory manifold. We hope to have dyno numbers in Dec. somr time on at least the first version and Jan. for the secound setup.

We are hoping for an 8-10 % gain in airflow with version 1 with no added portvolume to the heads over our stage 2's, there should be a big gain in velocity and trqu. from these heads as well as high RPM performance. These heads will also have relocated valve location to unshroud the bigger 2.08 valves on the factory bore! Alot of work but should produce some decent gains over our stage 2 stuff and hopefully warrant the extra cost involved.

More on the 2nd version later, the intake for these is not a derivative of the spyder intake as we have not physicaly done the manifold yet, sketches and calculations so far on that one.

the head gaskets and studs we use on the big No2/FI engines work great but are a bit pricey due to the amount of machinework involved in the block and heads.

More to come <img src="graemlins/burnout.gif" border="0" alt="[Burnout]" />