[Power Surge]

Originally Posted by 1blackbb66

Sal,
Why is it you feel that Cobra side pipes eat up so much power? Inherent design flaw? I have heard this before but all things being equal, (pipe size, muffler flow, etc) they wouldn't be any worse than an under car system on a Mustang.

Ray

Well, Cobra sidepipes are basically open headers with some kind of device to reduce noise. Most stock type sidepipes are baffle plate type (like a motorcycle muffler), and they totally kill performance. There are other better flowing designs, but basically most pipes people run to keep the car from sounding like an open exhaust dragster, chop power pretty good. Plus, with a regular under car exhaust the piping can help scavaging velocity, and you just don't get that with a Cobra sidepipe.

You have no idea how many people come to my dyno with expectations on rwhp, previously having their motors engine dynoed. The average IRS Cobra with a motor that makes 550hp on an engine dyno, will put down barely 400 rear wheel. That's a little over 25% loss. But a non-Cobra vehicle with a manual and IRS will only have about 15% loss.