Exhaust Question

[Ross W.]

I'm considering replacing the center exhaust section/resonator with separate pipes and a Dr.Gas X-pipe. I understand the center section is extremely restrictive, and I'm sure that can change for the better with what I want to do. But I do have a question: how good or bad are the rear 4 mufflers? If there were millions of 400s in the boneyards, I'd buy a couple of them ( front & rear ) to dissect them to see how they're constructed. Beyond that, I'm only guessing. Eventually a full system with S & S headers and a good muffler design will be done, but short term I think the center section replacement would be a good upgrade.

Thanks!

[Ross W.]

I'd like to add I searched the performance forum, and it seems my idea is pretty specific, in that I'm curious as to how good or bad the factory rear mufflers are, and replacing just the center section, and what that would do for me.

Regards,

Ross

[SKperformance]

I made a huge thread a few months ago with pics and explanations for the exact query you have.

http://us.lexusownersclub.com/forums/index...amp;hl=mufflers

[Ross W.]

I made a huge thread a few months ago with pics and explanations for the exact query you have.

Wow, thanks for that! I missed that one!

Much obliged!

[harjp]

I made a huge thread a few months ago with pics and explanations for the exact query you have.

http://us.lexusownersclub.com/forums/index...amp;hl=mufflers

Thanks for showing me what's under my car. So it's not a true dual exhaust, huh?

The resonators, are they catalytic converters? I wonder what eliminating the second one does to emissions.

And the O2 sensors -- there's one (or two?) in the exhaust manifold. Are there any further back?

I guess, since the "dual" exhaust is cosmetic only, I'm wondering what the possibilities are for replacing everything from the exhaust manifold back with say a 3 1/2" exhaust system.