I had Motor Machine in Arizona spec out this cam for my setup. but I think it is alittle extreme.

Lift INT EXH

.800 .736 not mechanically possible

Duration seat to seat

285 288

LSA 109

Intake centerline 105

Advance 4 degs

This is what I was given, and being that I'm still on a factory PCM and not a DFI I believe this cam to be unacceptable. If I were to us this cam the lift would be a max of 625/625. So what in the hell have I got here?

Randy

 

Did they know it was a SBC?.....lol

 

Ya, he knew it was a LT1.

Randy

 

Dayuum Randy, that thing would have to idle at 2K rpm

Have you actually bought it yet, or just getting their specs for what they think you need?

 

So, it's ~230/236 @ 0.050"? That's not huge. The LSA is kind of narrow for a street cam though. What I don't get are the lift numbers. What is the lobe lift? What CR is your motor?

Rich Krause

 

Rich, first off how did you figure the 0.050 duration? The cam I was running was a 228/236 @ 0.050 with .544/.568 lift 112 LSA. The lift numbers that I was given are not mechanically possible as told to me by Denny at motor machine, so I am suppose to use as much lift as my particular setup can handle. I really didn't think the duration was that big,285/288 seat to seat, since my previous cam was 280/288, but the LSA was what had me worried. Do you think I should try this cam or do you have another suggestion. Oh ya I almost forgot my CR is 11 to 1 and the lobe lift for the spec'd cam is .500/.460.


Mark, no I haven't bought a cam yet, just trying to find the right one.

Randy

 

Maybe when they said low lift they were giving the lift at the valve? the cam seems decent then , but that lift is crazy, I think the most I've seen a SBC is in the low 700s.

 

I would have to "run the numbers" to be sure. But off the top of my head, I'd say that the cam will have a narrow power band and not be very pleasant for street driving. I think the LSA is too narrow. As far as lift goes, when you start exceeding ~0.600" spring life gets pretty short.

Rich Krause

 

I've done some figuring along with somemore research and I think I'm just going to go with a 236/242 .600/.600 112 LSA. This should do what I want and being that the car never sees the street idle quality won't matter. Thanks for all your help Rich.

Randy