can somebody tell me what the cam specs are for the new LS7 Z06 engine? i would like to know both the intake and exhaust lift data as well as LSA. also what is the duration for the intake and exhaust @.050? i have heard that this new engine is using a 1.8 rocker ratio, is this true?
I only know the lift is .591. I don't know the rest. I'd like to know also. I thought I had it stored somewhere but I don't. Regardless, there is a lot of potential for more power based on what I've heard about the heads.
211/230 and .593/.588 According to Popular Hot Rodding
__________________
Come to the Z06 Fest!
Performin' Norman
Last edited by PerforminNorman : 10-31-2005 at 06:14 PM.
thanx 4 the reply Norman. i have been able to verify that the specs you qoute are indeed correct. so lastly the only figure that i am left to verify is th the LSA. i have heard that it is 120. can anybody verify this???
A 120 lsa......... No wonder it sounds tame at idle. There sure is a lot of potential. Better to put a 427 crate motor in your C5Z06 and build it right.
wow is right!!! those cylinder heads outflow AFR's 205 cc cylinder head by 48 cfm at .600 inch lift on the intake side. but this is because these heads have way bigger intake valves than AFR heads have. unfortunately the exhaust side needs major work relative to the intake side. now i know why the general put a big dual pattern duration on the exhaust side of the roller cam. this also explains why LG's headers are gaining so much power on this engine too. me thinks the ideal cam for this head to make more power and still pass emissions would be the following:
intake exhaust
lift .610 .615
duration@.050 220 240
LSA = 114
since the exhaust to intake ratio on the flow of the cylinder heads is a horrible .63% at .600-.625 lift, a cam of this sort would make about 20 more rwhp and should be good for a 100 shot of nitrous. since the engine has cast pistons i wouldn't spray more than a 100 shot though. also since the exhaust side of the cylinder head has such poor flow i would definately put LG headers on to help alleviate any potential for exhaust gas reversion back into the cylinder when using the juice. beyond this level you are gonna need to full port the exhaust side and install bigger exhaust valves to get bigger gains. and if you do that you are gonna need a header with at least a 1-7/8 primary.
fyi - these lift figures are based on the 1.8 ratio roller rockers that come stock with this engine. bottom line here is > there is no way people are gonna pickup anymore than 20 rwhp off a cam swap on this engine and pass emissions unless they do a full port on the exhaust side of these cylinder heads and put in bigger valves.
Last edited by Fast Freddy : 11-01-2005 at 12:20 AM.
Norman, assuming you were to stay with the stock compression ratio in order to run premium pump gas then i would run the following cam:
intake exhaust
lift .610 .615
duration@.050 230 250
LSA = 112
this cam would make about 30 rwhp more than the stocker. in order for these heads to take advantage of additional lift on the exhaust side they are gonna need porting and bigger valves. then you will have to fly cut valve reliefs into the pistons to make sure your valves don't hit your pistons. since the stock pistons are cast you might as well toss em and throw in some forged slugs.
Last edited by Fast Freddy : 11-01-2005 at 10:24 AM.
First, from a performance first standpoint, with with the probable need to notch the pistons, the Comp Cams LSK (if they work with 1.8 rockers) would probably be the highest power for a given duration. With 1.8 rockers in the .670+ range.
Second, the exhaust numbers also indicative of the whole exhaust. Clearly, this setup whats headers and a less restrictive exhaust. So the headers should be a big boost.
Third, with a 230+ exhaust (assuming you keep it at least as large as stock) you probably won't get over 220 or so on the intake, reducing the LSA to 114, and still pass emissions.
How big can you go with out emissions? It depends what you use it for. Some are being used for rock crawling (literally), and these will probably go smaller. With headers, a loppy idle, soft bottom end, and some noise, you probably could go into the 240s.
However, at that point shouldn't you sit and think about what you are going to do with a 650-750hp at the crank engine in a 3100# car without a roll bar. You won't be able to drag race it. That mix would be pretty unmanagable on a road course without a race suspension and tires. And the real racing version is built using a steel frame, allowing easier integration of a roll bar/cage.
AutoForums.com is the premier network of enthusiast-owned
enthusiast-operated automotive communities.
We operate more than 100 automotive forums where our users consult peers for shopping information and advice, and share
experiences and opinions as a community.
No wonder it sounds tame at idle. 
There sure is a lot of potential. Better to put a 427 crate motor in your C5Z06 and build it right. 
Linear Mode
