Anyone using the Lindsey 5" exhaust?

[Porsche-O-Phile]

I'm wondering if it's just "big for the sake of being big". I had my doubts about the 4" exhaust system reducing backpressure but they seem to have it reasonably well documented on their web site. The 5" system looks kind of neat and theoretically it should also reduce backpressure even further but there's no documentation or actual dyno data available. Anyone using it? Results? Opinions?

This will be mated up to a 2.8L turbo - shooting for around 375-400 RWHP.

[74goldtarga]

This post is probably on the wrong forum - you should re-post on the 951/944T forum. My opinion is that flow is going to be determined by the smallest tubing in your system, plus bends/intercooler/turbo etc. If you have 5" tubing on the intake side it probably matters but I would think that you do not. For your HP level I think 3 or 4" should be adequate and I doubt there would be a real increase going to 5". Just my 2c

[Porsche-O-Phile]

I'll x-post it there, but I think that forum gets very little traffic - a lot of turbo guys seem to hit this board but I guess it can't hurt.

Kinda' my thoughts too. I'm guessing the 5" is really just for show ("because we can") rather than anything substantial. I'll probably just go with a 3" or 4" setup.

[HondaDustR]

5" seems kind of insane overkill...and expensive. 5" stainless tubing? $$$$

[porsche4life]

Jeff, Take the claims on the lindsey website with a grain of salt. Feel free to PM me about that...

That being said... The 5" just sound excessive. That's up into diesel truck category.