Best downpipe for stock catalytic?
You can run a certain gas additive to get ride of ALL that although your car may run liek ****.
I simply Know a guy who does state testing
Fumes, flames, all of that, so what? You want power? If you keep a stock cat you will not only KILL your topend but limit all mods and Everntually cause engine knock as exhaust velocity will just be stopped.
I simply Know a guy who does state testing
Fumes, flames, all of that, so what? You want power? If you keep a stock cat you will not only KILL your topend but limit all mods and Everntually cause engine knock as exhaust velocity will just be stopped.
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From: Cherry Hill, N.J.
Originally Posted by mifesto
technically a very well tuned evo will pass idle inspection WITHOUT a cat.... in NJ they dont dyno your car so thats not a problem...
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From: Cherry Hill, N.J.
Originally Posted by umiami80
You can run a certain gas additive to get ride of ALL that although your car may run liek ****.
I simply Know a guy who does state testing
Fumes, flames, all of that, so what? You want power? If you keep a stock cat you will not only KILL your topend but limit all mods and Everntually cause engine knock as exhaust velocity will just be stopped.
I simply Know a guy who does state testing
Fumes, flames, all of that, so what? You want power? If you keep a stock cat you will not only KILL your topend but limit all mods and Everntually cause engine knock as exhaust velocity will just be stopped.
Originally Posted by inariv5573
Thanks for your info, but I don't like to take shortcuts. And I want clean upgrades, not stuff shooting out the back and having to put additives. Besides, it is possible to make good power with stock cat. Look at the Corvettes, Vipers, and Mustangs running around with legal exhausts making HUGE power. Not to mention they have factory backed warranties. Look at Hennesey, Lingenfelter, and Saleen.
I really don't think you can compare large N/A V8's with our boosted 4 bangers. The displacement (2L vs. 5-6L engines) they have makes all the power even with the super restrictive exhaust parts they have on the V8 cars. I really don't think your argument, is valid on that end.
I have a 3" catback and an RMR intake already and I just installed a UR downpipe and a Random Tech HF cat just this weekend. NO Cel and it pulls like a ****! Untuned!
I can only imagine how much better it would run with the MBC installed and a relflash/tune. 
Besides, it is possible to make good power with stock cat. Look at the Corvettes, Vipers, and Mustangs running around with legal exhausts making HUGE power.
The ones with BIG power Have High Flow cats. Otherwise the increased exhaust volume and velocity creates SO MUCH heat you may melt teh damn cat. Get a High flow cat TRUST ME!!!
Originally Posted by Wicked05
Actually...
HKS is 65mm...which equates to roughly 2.56" in diameter, which is the correct internal diameter. www.hksusa.com
HKS is 65mm...which equates to roughly 2.56" in diameter, which is the correct internal diameter. www.hksusa.com
Originally Posted by inariv5573
Which is the best downpipe for the stock cat? I keep hearing that 3" is the best, but if you have the stock cat, it defeats the purpose of the 3". That eliminates the helix. I know the Helix bolts to the stock cat, but what's the point? I know 3" makes more power, but with the stock cat won't I be better off with a 2.5" such as the HKS one? 
If you have the 10.5 turbo housing - stock DP is fine !!! All you need is a boost controller and axel back. Buddy of mine and I are even where I have a 2003 GSR with 2.5" turbo back exhaust and he just has a muffler delete pipe (nut 10.5 housing). People, if you have the means, get the 10.5 housing
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I'm also using the Tanabe downpipe, and it mates perfectly with the stock cat, and doesnt have any problems hitting the crossmember.
http://www.tanabe-usa.com/exhausts/downpipe.asp
It's 70mm and it also had an extra capped bung for EGT, which is kind of handy
Retails for 280 but i picked it up for less
The HKS is kind of weak for the price you pay IMHO...at only 65mm you might as well stick with stock.
http://www.tanabe-usa.com/exhausts/downpipe.asp
It's 70mm and it also had an extra capped bung for EGT, which is kind of handy
Retails for 280 but i picked it up for less
The HKS is kind of weak for the price you pay IMHO...at only 65mm you might as well stick with stock.
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From: Cherry Hill, N.J.
If I do go with a high flow cat, I will go with either Magnaflow or this place called xtreme converters. Apparently their converters are OBD 2, CARB, and EPA compliant. You can't beat that.
Originally Posted by inariv5573
If I do go with a high flow cat, I will go with either Magnaflow or this place called xtreme converters. Apparently their converters are OBD 2, CARB, and EPA compliant. You can't beat that.
Do you have a link to the xtreme? I am looking for a 3" cat right now that won't trigger a CEL.