to fit with mugen header
its a carsound cat, i dont know how they flow, so i need some input
i dont want a 2.25" if its gonna bottleneck the exhaust, but i dont want 2.5" if its gonna be too big and cause an area for the exhaust flow to loose its velocity
2.25"
or
2.5"
the cat would be a carsound high flow unit......
and should i get it with the 3 hole flange welded on it already and where should i get the O2 bung (front or back)????

the exhaust is a tanabe super racin medalion also if that helps

 

I did a search and found a similar question that I have but no one answered so I'll ask it again.

I'm getting a full mugen exhaust (header/cat back) and have decided to replace the OEM cat with a high flow cat. Will probably get the ODBII Compliant High Flow Cat made by Carsound.

My question is, what size do I need? 2.25" or 2.5"?

 

Anyone?

 

match it to your exhaust or header.

 

I'm not sure what the inside or outside diameter of the mugen piping is...

 

Mugen ID is approximately 57mm header, 54mm exhaust side.

 

2.5 in ..im running that with my apexi ws and it sounds great...at first i had 2.25 and it felt like it was struggling so i put a 2.5 and noticed significant gains in the higher RPMS.

Good luck

 

Are you sure it wasn't a placebo effect? Apex-i WS is 2" ID and unless you're running Mugen, GReddy or a custom header the ID is 1.8" header side.

 

forgot to mention that i have a modded dc header with a 2.5 collector..

the apexi ws 60mm=2.36 inches catback...

dont use the dc flexpipe..its junk..i replaced mine 3 times, then i finally put a 3bolt flange ..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Inextricabledrvr &raquo;</TD></TR><TR><TD CLASS="quote">the apexi ws 60mm=2.36 inches catback...
</TD></TR></TABLE>

Keep dreaming It's 2" off the catalyctic converter until the resonator and then about 2.2" ID (we're not talking about OD) though to the muffler. Then the WS shrinks down to around 2" ID again inside the muffler and then spits out. That's the reason why the WS is so quiet. It's not a true 60mm catback anywhere in the line, so I'm not sure what made you think it was? Most of the off the shelf systems are 60mm OD, just that the Apex-i WS is very restrictive compared to most.

 

thanks for the info...didnt know that..

 

I've got the 2.5" carsound cat, Comptech header and JDM Mugen catback exhaust.
It's the universal cat without the flanges or O2 sensor bungs and from what I can see it looks huge compared to the exhaust and header. I measured it and found that the ID is actually a little bit bigger than 2.5". I'd get the 2.25". I'm seriously considering using the stock one for now. The only thing that bothers me is that I can see a lot more
daylight through the carsound cat than the stock one.

 

That's good to know. I was pretty much decided on the 2.5" but after what you said, I think I'll get the 2.25".

Does Carsound make cat's specific to make/model of car? I want to get an ODBII compliant cat (w/ O2 sensor bungs) and flanges pre-welded on...

Has anyone looked at Random Technology?

 

carsound usually makes a universal replacment and then you ahvce the muffler shop weld ont eh flanges needed.
btwi rna a 2.25 inch test pipe then a 2.25 inch carsoudn cat and dyno testing showed no change in power. this was with a jdm oem header and apexi dunk exhaust.

 

https://honda-tech.com/zerothread?id=1016365

 

inlinefour.com sells carsound 2.25 with o2 bung.

 

are these the same as magnaflow cats?

 

yes they are.

 

thats what i thought thanks...i think if you buy it from them its cheaper too

 

i noticed this as well with my 2.5" carsound cat. its almost 2.75" OD
what were they thinking? anyways i was thinking of having them fit actual 2.5" piping inside of the inlet/oulet to remedy that. good idea or not?