Making Rousch 427SR EFI How to do?

[SP01715]

I drove a SPF with a Roush 427R that had been switched from a carb motor to an 8 stack set-up. The power curve seemed IMO to be screwed up. I was told that a different cam was used in the carb motor. Something to think about...

[PANAVIA]

Originally Posted by SP01715

I-- I was told that a different cam was used in the carb motor. Something to think about...

That is very true, low vacuum motors (radical) cams flip out the MAP sensors and the knock sensors (if used)

My idea-

E303, 1.7 Rockers, check for valve bind, advance cam 2 to 4 degrees and tune and look the F out.

[bobcowan]

Originally Posted by SP01715

I drove a SPF with a Roush 427R that had been switched from a carb motor to an 8 stack set-up. The power curve seemed IMO to be screwed up. I was told that a different cam was used in the carb motor. Something to think about...

You can get an EFI system to work well with a "big" cam - low vacuum signal and all. IMO, a big cam with a low vacuum signal is perfect for EFI. You don't have to worry about maintaining port velocity so much. Some, but not as much.

An 8 stack system (carb or EFI) works better with a cam that has a larger LSA, like 114*-115*. That prevents the reversion you usually see in the carb/TB throats.

A big engine with a big cam and heads can idle quite niceley at 800rpm's, cruise down the highway at 2,000 rpm's, calmly drive through a parking lot, and scream like a raped banshee when you mash the throttle.

How do I know this? Been there, done that.