Okay if this isn't adavanced enough (I think it has some merit) move me to LT1 tech. Anyway I am heaving my heads ported the numbers I should see are 260/215 @ .500 lift with 1.94/1.5 valves. What I would like to see is 500 HP at the crank. With an A4/2800 stall setup, cam selection has become a nightmare. I do know that i will proably add a 200 Shot as the bottom end has been splayed. That raises more questions as now i have to find a nitrous friendly cam as well. Here is what i have been looking at real close, and here is where i need to hear the advice the most. The following cam specs from Lunati Grind# 54756 232/242 @ .050 110 LSA with .510 .525 w 1.5rr Although i would probably use the 1.6rr. I want max power with some semblance of driveability.

Questions

1. Difference the LSA will make in NA Power vs. NO2 Power
2. What Custom Grind Cams from the guys that have been this route already
3. Driveability with each cam recommendation and application as well please.
4. What kind of times to expect with a standard weight car.

 

TTT cmon guys anyone???

 

Just got back home..........

Here is my shot at it.

I am building a 383 for a guy on the board, his flow numbers are very close to yours (within 2cfm) The thing you need to have done is have the heads flowed with the intake on it, then you will see the problem here. (I'm assuming that the exhaust is flowed with a pipe, because that's a good exhaust port if not!)

It will make the intake numbers drop to about 240 and exhaust will stay the same, now you have a 89% E/I ratio rather than your previous 82% E/I ratio. (thank Jason Short for making me look into that!)

We are going with a .600 lift cam and the duration is right around 230 for both on a 112 LSA. The problem is that your cam to fit the heads NA is going to be a single pattern cam rather than a dual pattern like you are looking at, and the LSA should be around 112 with that kind of duration. Now on the other side of the equation you are looking at a N2O cam which will use a split like you stated except it needs about 114-116 LSA to work well on N2O.

I personally think that the N2O will depend more upon the LSA than on the extra exhaust duration, but even on a LS1 that likes single pattern cams more exhaust duration helps N2O power there. I would look at a 230-236 Intake durtaion, with a 236-244 exhaust duration on a 114-115 LSA. That's about what you should be looking at for what you stated.

That's just my thoughts.........

Bret

 

I have a 383 and I went with the cc306 cam. I daily drive this car and I put a TH350 with a 4200 stall. With no computer work I put down 394hp and 395tq. on the dyno. Thats with no computer work. Just check my web page for the flow numbers on my heads.

 

My engine builder said the same thing about the intake.

The heads flow great but once you put the intake on it drops to 235cfm.