Here is a link to the Ultimate Racing 3" test pipe. Price is $175. Much cheaper alternative. Any shop should be able to put the o2 bung in there for you for pretty cheap, or you can just tap it yourself and have them weld around the tap hardware to ensure a tight seal. I bought one used from honda-tech for $100 shipped with the o2 bung alread installed...

http://www.ultimate-racing.com/Products2/S...K_Exhaust.shtml

John

 

Are there two 70mm test pipe? The Invidia and T1R?
One of the vendors on here quoted me almost $200 shipped for the T1R. I thought that was a bit high since I found the Invidia for $85 shipped elsewhere. I don't mind spending up to $200 for 3" or larger, but not for 70mm.

I really wish there was a 3" or 80mm test pipe. A lot of the turbo guys probably don't want 3", then 2.75", then 3" again in their exhaust systems. I know I don't.

I saw the Ultimate Racing one. It looks ok, but doesn't have a flat front flange so it may not be possible to weld a v-band flange to it.

FYI- Here's my current setup. I already have a 3" test pipe, but I'm thinking about swapping my exhaust to something with a stock flange. If so, the test pipe will no longer fit. Luckily, the cat still will since I never modified the rear flange. You can also see the offset/tilt of the test pipe/cat.


Tim

 

3 INCHES IS 75mms

I dont think 75-70 would be a bottleneck at all. 5 mms is a quarter inch

 

I thought the Greddy kit (and most kits for that matter) were plumbed so the DP flows right into the stock cat-back exhaust... If the flange does not match the stock exhaust (on most kits they do), it is not really a "kit" and is more of a custom turbo application.

Just my $.02. This one should work with the Greddy kit if the Greddy kit bolts up to the stock cat...

And that extra 5mm amounts to about a gain of 7.5% of total pipe opening area (when compared to the 70mm). I believe the reduction in back pressure is greater than that, as pressure I believe is non-linear with pipe diameter (I thought it was exponential), but I could be wrong... Its the difference between 2.75 and 3.0" piping... And if you factor in the air turbulence that would be created around the 3" --> 2.75" flange at the down-pipe, the back pressure would be even greater, right? I think the idea is to increase exhaust volume moved coupled with an overall reduction in exhaust speed (reduces back pressure). If I am mistaken, please let me know. I am by no means an engineer (accountant, actually).

Has anyone tried removing the resonator plate that is around the stock cat, and installed in on a test pipe (via welding) to reduce any drone? I am not sure if there will be any drone, as the turbo is between the TP and the engine...

John

 

Yeah, Still unsure of what to do, someone posted this site, I may try them

http://www.ultimate-racing.com/Products2/S...K_Exhaust.shtml
Seems to have a "3 T/P with a "Mechanical CEL Fix", not sure what that means,
Also I found a Tuner in NJ, he said a tune will be around $400.00, does that sound reasonably, and then 100/hr for a Dyno

 

anyone $400.00 for a tune expensive?

 

depends on what you are tuning and what your goals are. They can run anywhere from $200-1000+ depending on how many maps and how much dyno time vs. street tuning you do. $100/hr sounds alright... Stage6 is $150, but they have a dyno dynamics (nicer than a dynojet), so it sounds about right.

It sounds a bit expensive for E-manage tuning. AEM it would be a good price, but all the parameters and everything should already be set in the Greddy pre-tune that you already have. He should just be messing with AFR and maybe timing (depending if E-Ult has that capability).

Mechanical CEL fix is the spark-plug de-fouler mod someone mentioned earler. Some TP already have them welded on. Others you need to screw in the de-foulers before you screw in the secondary o2 sensor...

And I am not sure what the physics of it are (maybe someone can chime in), but I believe if you run from your 2.75" Greddy down pipe into the 3" test pipe / exhaust, there is going to be a good bit of turbulence where the test pipe and the down pipe meet (the test pipe flange should be "filled in" by about 1/8" all the way around, as the downpipe has a smaller diameter)? I would think it would be smarter to go with a 70mm test pipe and a 70mm exhaust, just to keep the pipe diameter smooth and consistent (thus reducing turbulence and back pressure). 3" I think would be preferred if you had a 3" downpipe (like some kits do)...

John

 

[QUOTE=jwa4378,Feb 13 2008, 08:45 AM] depends on what you are tuning and what your goals are.

 

I just bought the greddy kit and want to know what size the downpipe on the kit. My guess is it 70mm?

 

yea correct, I jut ordered mine this morning