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Old 03-02-2010, 02:42 PM
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bobcowan bobcowan is offline
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Join Date: Feb 2007
Location: Colorado Springs, CO
Cobra Make, Engine: Backdraft, supercharged Coyote
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Quote:
Originally Posted by SP01715 View Post
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.
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