So Im planning on upgrading to a custom 3" mandrel catback and wanted to get rid of the last bottleneck which is the cat. While browsing on eGay, I ran into a universal 3" resonated test pipe. I know being resonated will restrict airfow in comparison to a straight/test pipe but I dont want it to be obnoxiously loud or raspy.

Which leads to the true purpose of the thread: how long is the OEM cat from flange to flange? Want to figure how fitment will be. The custom mandrel shop Im going to wont touch the cat. Only the B and back.

Comments and advice about this next project also welcomed!!

Link to the 3" RTP below:
http://cgi.ebay.com/ebaymotors/Unive...#ht_1219wt_772

-DB

 

Clashez would like this, its 3" inner dynamiter.

OEM cat is 12.5" long.

 

there isnt going to be much pressure drop or decreased velocity with the resonator. I wd replace the cat with that at least. Keep the noise/rasp to a minimum.

 

schmelly, hows the piping done on your exhaust? From 2.5" to 3" right? How is that made to work? Flared piping to flanges of the same size?? Always wondered this..

 

> 2" header collectors
> 2.25" y pipe primaries welded to 2" collector flanges
> two 2.25" merge into single 3"
> 3" test pipe
> 3" exhaust

 

Ahh I forgot you were running a custom y. Dont wanna touch my headers/y (OBX) so my customizing will be from the cat and back. Will see if they can flare a pipe to fit one end of the test pipe (3") from the y pipe (2.5"). Flanged would be nice but if not, I may just get it welded in.

 

A 3" flange will bolt up to a 2.5" flange. I had my 3" exhaust bolted up to my 2.5" test pipe, I also had my 3" y pipe bolted to the 2.5" test pipe for a short time as well.

 

You took a load of stress off of me bro!!!! Much appreciated. Really need a rep system for ppl on here. Def get a +1 from me!!

 

lol No problem.

 

Do you not have an existing cat to measure?

Also, the cat is hardly a restriction. You'll pick up 1 to 2hp if you're lucky. W/o a cat, your car will be stinky. Keep the cat and focus on getting a really good resonator in the bpipe. My 2 cents.

 

No space to jack car up and look. Also seems my cat is going out anyways. Caught a good whiff yesterday. Car is being built for a S/C thus the upgrade to 3" all the way back.

 

Nevermind. Answered my own question. Power of the interwebs

http://cgi.ebay.com/ebaymotors/2-bol...ht_2352wt_1165