TTi medium tube header, and running a cat

gilly02le · Post by **gilly02le** » Sat Dec 02, 2006 2:08 am

Anyone running a TTi medium tube, im looking into getting one to replace my obx short tube, and im just wondering if im still going to be able to run a hi-flow cat, installed after the header. I have the obx setup and from what it looks like, the new header would have the cat in about the same spot as it is now, on the end of the obx downpipe.
E-tests in my area or i'd cut the cat all together.

white2000neon · Post by **white2000neon** » Sat Dec 02, 2006 10:39 pm

I have a lth which should be similar to the tti just a tad bit longer and i'm using a hi flow cat. I ran it for one day without a cat and it was so raspy i was embarrassed. Now with the cat it cut down the raspyness a whole lot.

gilly02le · Post by **gilly02le** » Sat Dec 02, 2006 11:25 pm

ok cool.. yeah ive run with no cat before, short tube header, 2.5 inch from the header flange back, and it was insanely loud.
Im planning on replacing my entire exhaust system, gonna get a tti-mid tube, hi flow cat, and 2.5 ss piping and a resonator to cut down the rasp.. should work nicely, just have to find the right muffler!

MoparNeonMan · Post by **MoparNeonMan** » Fri Dec 22, 2006 11:57 pm

Ive got that exact setup now....Id highly recomed a solid upper mount and filled lower....adds vibration to the car...but allows you to run w/o a flexpipe.

gilly02le · Post by **gilly02le** » Sat Dec 23, 2006 8:40 pm

well i've allready got the race stiffness prothane M.M inserts, and there is virtually no engine flex at all.. im guessing you say that ill need these because my header will hit my firewall???
and also.. will i have to move the coolant overflow bottle, very easy, but im just wondering..

MoparNeonMan · Post by **MoparNeonMan** » Sun Dec 24, 2006 12:08 am

The stiffness recomendation is so that you dont have to use a flex pipe. The stock cat will not fit...tho Im sure you know that.

The overflow is in the stock location. No need to move it. Ive got pix somewhere and Ill see what I can find for you.

gilly02le · Post by **gilly02le** » Sun Dec 24, 2006 12:21 am

ok sounds good man... and yea, the stock cat is garbage lol IMO.. definatly not a lightwieght or hi-lfow peice.. so ill be replacing the hi-flow that i have that is damaged, with another one. But right now ive got the obx header and downpipe.. its a pretty good setup because it comes with the short tube + downpipe with flexpipe and everything... but ive decided i want a longtube or mediumtube because of the obvious performance gains.. my only complaint about the header is the flange is kinda poorly designed.. its kinda restrictive, like it merges to a 3 inch collector and then has a 2.5" flange and 2.5" piping after that.. so theres a bit of a design flaw there...

MoparNeonMan · Post by **MoparNeonMan** » Sun Dec 24, 2006 6:58 am

Which header has the flange issue?

gilly02le · Post by **gilly02le** » Tue Dec 26, 2006 12:22 am

the obx... its a 3 inch collector, to a 2.5 inch flange.. i'd rather a design where the flange is the size of the collector, so that theres no bottleneck there.

think there is really any point in me running 2.5" piping from the cat back once i replace my exhaust..what ive got on there now is 2.5" but its aluminized steel and is rusting like crazy so its time to go.

I'm just thinking, if an srt-4 can make 230hp with 2.25" piping, i'm kinda feeling like i should go with some smooth bend 2.25" S.S, might also help me keep the rasp and noise down a bit. any thoughts?

MoparNeonMan · Post by **MoparNeonMan** » Tue Dec 26, 2006 10:06 am

What kind of muffler/resonator are you running currently? What you use and where you place it will have a dramatic effect on the sound of your exhaust.

Of course comparing it to SRT piping is apples to oranges. Hell you could run a 6 inch length of 5 inch pipe off the turbo...NA motors generaly (NOTE: I did not say all as I got hit on this before on the other .org) need a smalliwsh pipe between 2-2.25 sometimes 2.5 inches to maintain back pressure to help scavange the dead fumes from the motor. Now Ive been told that the Neon motor doesnt have to worry about it and Ive been told it does. Im old school. Untill I see a system above 2.25 inches (that makes any decent power gains, please if there is one someone tel me so I know)...Id stay with that.

gilly02le · Post by **gilly02le** » Tue Dec 26, 2006 12:02 pm

exactly what i was thinking.. ive had tonnes of people on here say that backpressure matters.. and that it does not.. well heres the way i look at it, you can run with no backpressure if you a: have a v8 or B: have a turbo..

right now for a muffler i have a strait thru style muffler, 2.25 in, 3 out.. silencer installed as well to keep it quiet, but im looking to off this setup because i can literally feel a big loss in the bottom end, if i remove the silencer from the muffler. i want to run a true muffler and probably a dual setup, because my bodykit has outlets for duals.. porbably comaro style muffler and then two like 2.25 tip on either side.. keep it clean lookin, because right now.. my exhaust system looks like ass and is starting to leak like a motha! ive got some pics of it if you wanna see how bad its messed up.. hit a skunk a couple months ago and broke the lower o2 sensor and cat..lol

MoparNeonMan · Post by **MoparNeonMan** » Tue Dec 26, 2006 12:38 pm

gillyo2le wrote: ive got some pics....hit a skunk a couple months ago and broke the lower o2 sensor and cat..lol

post that ish man!

gilly02le · Post by **gilly02le** » Tue Dec 26, 2006 4:58 pm

here are some pics of what the exhaust system is currently lookin' like, balllz lol. the skunk ripped the o2 sensor wiring right out of the sensor, you can see the 2 of the 4 wires still hanging down there.. it also mangled the clamp holing the section after the cat on.. and i had to get a buddy to jimmy rig it up for the rest of the winter. The sensor wasnt turned down to the ground like that before, it was much higher, ive just turned the cat, since then, to keep it from touching the heatshield.. in the spring i will tear the whole mess off and replace it all..the skunk also got caught on the heatshield and tore some of it, who would of thought a skunk was so solid... lol

the first pick is just both dowpipes, in comparison, off of the car.
stock vs aftermarket dp
http://img73.imageshack.us/img73/1778/dsc00346kp0.jpg

damage shots/shady temporary fix lol
http://img164.imageshack.us/img164/1734/dsc00362nn6.jpg http://img105.imageshack.us/img105/6374/dsc00363al8.jpg

and yes, i do expect to get some comments about how shitty the exhaust looks and thats fine.. i agree fully and thus why its getting replaced with something proper.

MoparNeonMan · Post by **MoparNeonMan** » Tue Dec 26, 2006 5:33 pm

OUCH! That sooks like ish...glad ur dumpin it.

Where are you getting ur TTI from?