Now What? The heads are supposed to be ls6 but they are not .Will there be any power loss or gain.So I have a set of LS2 heads and trying to find out if 01 head gaskets and bolts will work on these heads to my 01 C5. I am looking for a cam to pull mad power out of the corners and beat the living crap out of a 07 GT and 99 Cobra. I am not looking for maximum power on a Dyno; but great road coarse horsepower and torque. Cam considerations are: G5X3, Vengeance Vindicator, Trickflow Stage 2. I have springs for a .600 lift not trying to any bigger.and thinking of staying under 224 duration or may be 230 max

 

I believe the LS2 heads are = to 01 LS6 heads.

As far as cams maybe somehting along 224-228 to 228-232, just tighten up LSA to 111 or a 112. Maybe look at doing a thinner head gasket. Your head/gasket combination will also dictate cam specs and PTVC.

The G5X2 is a great cam as well @ 232-240 but exhaust lift will exceed .600.

Any number of cams will work. Do a search. GL

 

The only difference between LS2 and LS6 heads are the sodium-filled valves. Since you have LS2 heads you DON'T need different length pushrods. LS6 valves are longer requiring .025" shorter pushrods. The power each make are the same, they are the same casting...

Relax, you are actually better off since your pushrods will work.

Also, bolts and gaskets are the exact same between LS2 and LS6 heads...

 

Believe the post about equality w/LS6 heads is accurate. I am certain that the ports are EXACTLY the same, but not sure if combustion chamber volume is or not. Also not sure if the same valvesprings are installed, either. But I am pretty sure that chamber volume difference, if any, would be VERY slight. My main concern would be how much lift the valvesprings would handle, but I believe you are going to aftermarket springs anyway, so I guess this wouldn't be an issue in your situation.

 

As long as you didn't pay a premium for the heads (for the more expensive LS6 valves), you are OK. I got very frustrated with these heads when they first came out as everyone was passing them off as LS6 and they weren't. Not that there is anything wrong with the head, but the sales pitches were very mis-leading and only when asked would the seller admit they were LS2 heads.

You still have a good set of heads though

 

I wouldnt suggest the Vindicator or MS4 for a road course or ultimate power under the curve... Both of these cams are more top end horsepower cams. I would suggest something like our VRX4 or 5 depending on how radical you want to go. Give me a call at the shop if you would like to discuss these more in depth.

Also, your heads are fine. As said above, as long as you didnt pay LS6 pricing then you didnt get jacked. The LS2 heads are similar to the LS6 heads in every aspect with the exception of the LS6 heads having the lighter sodium filled valves.

Ron

 

The LS2 head is identical to the LS6 head from a 2001 Z06. There is no misrepresentation if they came off a 2001 Z06. It is just that they changed the exhaust valves to sodium filled in 2002. I really do not think there is much benefit to the exhaust valve change to make it work more power over the standard valve. Just a little FYI any aftermarket head you by probably just comes with stainless steel valves. They do not have Sodium filled ones.

 

Cam for road / track days?

I use a comp cam 224/224 .581/.581 112 XeR with a 6750 red line.

224/228 or no more then 228/232. Keep your lift to .600 or under and that will save your valves train. But every one has different opinions.

Great springs are a must.

The challenge with so many heads on the market is IMO they are made for drag racing and dyno queens. Road Race heads need small runners for high velocity air into the cylinders which helps with lots and lots of under the curve low to mid range torque. Which means get up and gone our of corners, time and time and time again.

No need to go with a lift above .600 as most heads do not flow well above a .600 lift anyway. so why put a cam with that kind of lift? There might be a reason, and I would be the first to admit I just dont think that kind of lift is needed. Besides the LS6 intake and TB just do not allow that about of air needed for that kind of lift. If there is a reason I would like to know.


Good Luck

 

You are RIGHT ON with your statements about going +.600" lift. In a recent discussion with Tony M. about this very subject (And-lets face it-few, if any, are MORE qualified to speak on what works in a Gen.III or, especially, an AFR head, of which I have a set of CNCed 225's). He told me straight out that even the 225's are, to use his wording, "all done" at .600 lift. Sure, you may go above .600 for extra power, but in the end, it will be the extra duration that is achieved when you go to that extra lift, as you can only ramp up so quickly when stopping at .600 lift. And your "Great Springs" statement is absolutely right on. I have a very early set of 225's, bought in December of '04. There was a mistake made on AFR's part when the installed height was set (Which Tony and the gang at AFR have have taken care of-most graciously!) I installed Comp 921's (To fix the broken originals) and, due to improper shimming of the originals at AFR's shop when they were brand new, they were installed .100 TOO SHORT!!!! I didn't catch AFR's error, either, as I was told that I could just "swap them out" and all would be well with the world (Provided the original shimming was right-which it wasn't)! Instead of being installed at 1.800 or close to it, they left AFR's shop shimmed at 1.700!!! As some may know, this spring is "only" good for .650" lift. Taking that 1.700 installed height and subtracting my .600 lift cam, the spring "thought it was seeing a cam with .700" lift- FOR 25,000+ miles!!!! And running VERY NEAR coil bind!!And- not ONE broke!!! The original ones I ordered with the 225 heads DID break, the first on immediate start-up, but went un-noticed by the builders, and the second broke-which I caught right away, only a mile from home. Thank GOD they were dual springs, like the 921's are. It saved my engine-and a lot of VERY hard feelings and possibly worse. Get a GREAT SPRING, and IMHO, make it a dual one. Just my .02

 

Your post also talks of "port velocity". Good point! In a post recently on another LS1 forum, I saw a post on a dyno run with AFR 225's "against" some L92 heads. Both were CNC'ed, and the AFR's were over 20hp up on the L92 heads, at peak power!!! High CFM DOESN'T mean "better", though most see it that way. I have a bigger motor, a 427, and recently asked Tony what he thought about adding the factory LS7 heads, over his 225's-would it make more power? His reply was, "It probably would be make a little more on the high end, but seeing as your 225's might be, VERY SLIGHTLY, a little on the small side for a 427 cube motor, your port velocity would definitely be down by going to the larger ports of the factory LS7 head, and this would cause a slight drop in your low and mid-range torque, not to mention fuel efficiency". I thought it was quite a statement from a guy who's bread and butter is in aftermarket head design, and he told me that he felt I would probably gain some top end power if I switched to the factory LS7's!!! Tony is a STRAIGHT UP DUDE, for sure. And it shows just how right on you are about port velocity. I can remember years ago, another "head guru", Jerry Branch, of Branch Flowmetrics, said "You can't trade volume for velocity". Still holds true today.