[Power Surge]

Originally Posted by neverwouldof

Maybe i'm expecting to much.... but how does a 427 go from 603hp at crank to 394 whp when there is hardly any backpressure in a cobra. From all the other threds i read 15% was the going rate. The Dyno shop guy says he usually see's closer to 12's. Viper in there 505 crank and 424 whp with muffler system untouched..... it's crazy i tell ya. Only thing i can figure is the air/fuel getting to engine. If you looked at engine build up... it has some nice pieces!

Two things kill the engine to wheel hp in a Cobra... exhaust, and IRS. The IRS soaks up a ton of power, especially if it's the Jag setup with no upper control arms. The other thing is the Cobra exhaust. Most Cobra side exhaust setups zap a good 70-100hp from a motor. Your motor was dynoed at 603hp, but that was with real tuned long tube header, not Cobra side exhaust. The problem with improving the Cobra side exhaust, is the mufflers that hurt the power the least, are loud as hell.

But even with 18% loss (which is what I use for most Cobras), you're still missing some power. You should have your timing checked, and make sure you're getting enough advance. That was the issue with the car I had here. Fixed the dist issue and it picked up another 25rwhp. You might also consider switching to a nice 1x4 intake and carb.