For sh#ts and giggles.
 

What's best full exhaust regarding power, don't care about sound, raspy, cats or cost.

Outright performance!

Cheers.

P. S - n/a application.

Probably full Nameless 3" engine-back. I'm not aware of any other full 3" systems in production.

Perrin has had a full 3" header back on the market for a little while.

^^ Almost, they didn't have a 3" overpipe.

Is there proof that 3" makes a gain on these cars NA?

I'm with mrk1. I'd like to see real gains through the power band. 3" may only provide a very peaky TQ curve, scavenging at lower RPM on a full 3" system is probably going to be crap, worsening, or at least not improving power delivery.

3" chokes at low RPM but has good top end. That's what I experienced on my Nameless 3" before I sold it. Couldn't stand the rasp fartcan sound. Power gain is negligible unless you're turbo.

Your definition of flow choke and mine must be very different.

How about the lightest exhaust? Best performance should take into account power gain AND weight loss.

He didn't really say that it chokes the flow. I think he was using it colloquially to say that it doesn't work at low RPM. With that said, 3" pipes probably don't provide for enough exhaust momentum at low RPM, and thus bad scavenging, you COULD say that it is choking, the flow.:mad0259:

I'd agree a full 3" system should be the best, and while its probably too much exhaust for a more or less standard engine it won't hold back a supercharger install so if your're considering that for the future then 3" is the way to go

^ This.

What about a Tomei system? It's way light!

I agree with this guy, let's talk about weight.

The weight savings between the axlebacks is negligible in the long run. I'm more concerned with aero in the rear if I want to nitpick about something that could affect the car more. I'd rather put the money saved by going with a less expensive exhaust system (like a greddy sp elite axleback) into reducing unsprung weight than reducing sprung weight.