redgsxr01

I’m need a cam and rockers to complete my build. Well to complete this portion of it. I have a 99 Z28 M6 with stock bottom end. I have a set of LME stage 3 243 heads milled down to 58cc, headers, full 3” exhaust, 75-150 wet shot of N2O, 38 lb injectors, and Volant intake. Literally everything else is stock. I'm looking for something that is very streetable, although its not my DD, thats were it will spend most of its time. I know there's ton's of cam threads out there but I'd like to here peoples opions about cams for this setup.

Thanks in advance for your input

redgsxr01

Also im not 100% sure what the compression is going to be. I was told about 10.9:1 with .056 gaskets. if anyone knows for sure then chime in.

mark21742

With a stock .051" head gasket I came up with 11.5:1 which is a good ratio, but you will really have to watch your PTV clearance... I'd look at something around a 228 on a 110 lsa

garygnu

stage 3 heads mite have too big valves for a ls1 bore.the valves are close to the cylinder wall ,hurting flow.don't do the 228 cam 110 lsa,too much pressure.you have high static pressure you need a cam to make a safer dynamic pressure ,if you want to use pump gas.if you don't mind fly cutting the pistons there are a few cams to consider.also consider a custom cam.maybe look at a ms3 cam pkg too start.or look at a thunder racing cam pkg.EPS has a big cam you mite consider.

redgsxr01

mark: I just found a calculator and I got about the same. Do you know what the deck clearence is on a stock LS1.

gary: The heads came off an ASA ls6 and were not exactly sure if there stage 2 or 3 but they do have bigger then stock valves. The pistons in that motor had very small valve reliefs but they were dome pistons. I will check though. It was a GMPP ASA cam on a 109.

mark21742

Most of the ls1 blocks run around .005" out of the hole.

You probably need to fly cut your pistons to get valve clearance, and this will drop your compression down alittle.

FYI I'm running 12.56:1 scr with 8.25:1 sex on 93 pump gas with full timing and 0 knock

redgsxr01

Thanks mark. I'm talking AI right now to get a custom grind done. They're telling me that they can't guarantee me P2V clearence either. I actually came up with 11.26:1 as the compression with .052 gasket. the piston dome on the stock ls1 is 0, right?

mark21742

Yup It's 0.....it's a flat top

If you have the engine out and apart now id call a few local machine shops in your area and get prices to cut a small valve reliefs it the pistons....it shouldn't cost that much, and then you'll know you can slam the engine right back together when you get the cam....it took about 4.5 weeks to get mine back from the machine shop, but I did a lot of damage to it first lol

180ls1

iTrader: (4)

i would say something like a 224/228 or 228/232 on 114. it will not drive like stock but somewhat close and wont buck or surge a lot with a good tune.

redgsxr01

mark: Yeah that would be ideal, but the whole idea was to be able to do this without pulling the motor. If I'm going to have to pull it then I'm prob going to go with an after market rotating assembly.

180: Just want it streetable. If I wanted it to drive like stock I would have left it stock.

mark21742

Ok then look at something like a split duration 224/228 on a 110lsa and stay under .600" lift.

Just really look close at your PTV clearance and you might have to advance the cam afew degrees more to het your clearance...or you MIGHT just have your needed clearance....but check good

PREDATOR-Z

220/226 114 LSA, advancing reduces PTV on intake, retarding on exhaust. I would get the cam straight up and while measuring PTV, I could advance it up to 4*.
Lift has little to do with PTV clearance. So max lift should be partialy determined by springs on heads and the head's ability to move air at that lift.
Also lobes will come into play for DCR purpose.

However, as mentionned above, I would flycut properly and run a 228ْ>230ْ range cam with 5>9ْ overlap.