Shmee

iTrader: (3)

What sort of materials are you going to use? Are you going to use extruded die-forged seamless tube and 90° bends cut to fit or mandrel bent tube or exhaust shop pipe? Mufflers? Ys?

What you use will have almost as big of an impact as how you build it!

LSVIP

As far as pipe material, it'll be whatever is most readily available I suppose, probably find someone to ceramic coat all of it since I have a buddy who can weld it once I have it together.
I reconsidered the shapes used, probably 2-X-Mufflers-2

Shmee

iTrader: (3)

i would suggest better metal and components over ceramic coating.
Gains from ceramic coating will be zero and the cost would be better served put towards some high quality 304 or 316 Stainless. tube and components.
Vibrant 304 ss tube, bends and flanges with Magnaflow is probably your best bet for reasonable priced and long life.

Sewpra

Drifter, are hollowed out cats a bad thing? I did it to mine and within the 2K km's I've put on since doing it I noticed a performance increase without a doubt, at least one of my cats was bad though. I wouldn't say the sound is necessarily preferable though.

LSVIP

Thanks dude! I'm gonna talk to my buddy who welds about it, as I'm sure he has knowledge of readily available stainless at a good price!

PureDrifter

iTrader: (10)

yes bad. Creates a lot of exhaust turbulence and negates most scavenging from the crossover.

Beats clogged cats but not by much.

Shmee

iTrader: (3)

You should sleeve a hollowed out car is possible, it's much much better than a giant void.

Greg5OH

yes hollow cat is bad. Is is a larger cross section than the pipe and am increase in volume which equals-lower velocity.

LSVIP

I'm just deleting the cat and resonators, keeping two performance mid mufflers.

Shmee

iTrader: (3)

Unless your cats are pooched, there's no gain to removing them. And they are better for the world to have them....

LSVIP

Does it get louder?

Shmee

iTrader: (3)

Yes, and they also clean the emissions coming out.

I'm not a tree hugging hippy, my carbon footprint is massive, but I don't disable emissions devices on street cars.

Boyscout

iTrader: (3)

ive got some pics of my full custom exhausat on my build page. i have noticed a great increase in power, but im also running a blower, so the full exhaust (w/ no cats) really sped up the flow


https://www.clublexus.com/forums/ls4...t-colosus.html

LSVIP

This is awesome! Congrats on that sweet S/C setup! I'm trying to find headers at a reasonable price, but I heard they're a ***** to install. I was just talking to my buddy about running 2 Y pipes instead of an X pipe, how does it sound?

Boyscout

iTrader: (3)

Sounds amazing. Deep and throaty tone, but thats the way I wanted it to sound (I know some owners like the quietness, so my set up would not appeal to them)