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The Cuban Stig
09-20-2013, 03:48 PM
Hey guys, I want your opinions and knowledge on deleting the catalytic converter. Would it be a smart thing to do? and would that bring any risks?

Abarth Five O
09-20-2013, 04:21 PM
For track use and/or if you're not concerned about cel, noise or emission regs in your state, a decat DP alone will probably give u a little more boost than a HF cat DP, and significantly more boost than the stock DP. For street use, a decat DP will be hella loud unless you install a resonator mid pipe or muffler in the rear. R/R recently released a new, ceramic coated open decat DP. Madness also sells a chrome plated decat DP.

DuckDodgers
09-20-2013, 06:00 PM
On the whole, current cats don't really offer a whole lot of restriction. You might see a few horsepower (2-8??) from the delete, the car would be fractionally lighter, the exhaust would be defening and your OBD II would throw a CEL. There are ways to fake it out, but my base question is why? Removal of the catalyst and operation on the public roads is a Federal Offense...seldom enforced, but if they get pissed at you, it can get ugly. Some states make you take a car cited for being too loud to a mechanic, who would then refuse to certify the vehicle without a catalyst (or face loss of license, fine and jail time). Most states with fine you...for example, the Texas fine is up to $25,000 for bypassing emissions.

For track use, who cares; you every drive on the road be ready to accept the risks associated.

musicsurf
09-20-2013, 07:30 PM
On the whole, current cats don't really offer a whole lot of restriction. You might see a few horsepower (2-8??) from the delete, the car would be fractionally lighter, the exhaust would be defening and your OBD II would throw a CEL. There are ways to fake it out, but my base question is why? Removal of the catalyst and operation on the public roads is a Federal Offense...seldom enforced, but if they get pissed at you, it can get ugly. Some states make you take a car cited for being too loud to a mechanic, who would then refuse to certify the vehicle without a catalyst (or face loss of license, fine and jail time). Most states with fine you...for example, the Texas fine is up to $25,000 for bypassing emissions.

For track use, who cares; you every drive on the road be ready to accept the risks associated.

I have to disagree. The stock DP has a HUGE restriction at it's outlet. Those that have replaced the stock DP with either the Road Race high flow or decat pipe have reported a noticeable difference. It's not just about the HP either as the turbo is able to spool faster with the decreased back pressure. I would recommend going with a dp that has a high flow cat to avoid the increased noise and smell.

dylansi
09-21-2013, 02:05 PM
As Abarth Five 0 stated it is loud and I cant stress that enough. I drove around with a decat DP installed for around a month and decided enough was enough. Through my Torque app on my phone I boosted 19.9 PSI consistently without a cat and an exhaust leak (I did see it log in the 20s and if I would have fixed the leak, I believe I would have seen more), with high flow DP I now consistently run 19.7 PSI. Decat pipe felt slower to me and my wife BUT it could be that you no longer have that intense rush of boost pressure instead with decat it was smoother so felt slower.

All of that aside, I will end up with a decat pipe on again once one is out with a larger exit. If you want a TMC decat downpipe I still have mine sitting in the garage, send me a PM.

DuckDodgers
09-24-2013, 06:09 PM
OK, musicsurf...the downpipe has the restriction, not the cat, so my point is correct on the cat.

The downpipe is another matter, as you pointed out. Remember that if you blow an engine or throw a code, if you've replaced the downpipe (or removed the cat), they will likely deny the claim. Also remember the computer is storing a lot of data, and if you do something that allows higher than standard boost, I expect that would be logged and used against you. Just my $0.02.

jabird101
09-24-2013, 08:22 PM
Would it be a smart thing to do? and would that bring any risks?

Yes it does bring risks... To my lungs and all of those that share the planet with you. There is a reason we have these devices. I have no problem having a swap out with flanges for racing and track days, but when you are on the road please do the world a favor and keep your cat on. Better yet find a performance cat and get the best of both worlds.

musicsurf
09-24-2013, 10:40 PM
OK, musicsurf...the downpipe has the restriction, not the cat, so my point is correct on the cat.

The downpipe is another matter, as you pointed out. Remember that if you blow an engine or throw a code, if you've replaced the downpipe (or removed the cat), they will likely deny the claim. Also remember the computer is storing a lot of data, and if you do something that allows higher than standard boost, I expect that would be logged and used against you. Just my $0.02.

The OEM cat in the dp is made to filter a lot more than a 200 cell meaning more restriction as well. As far as warranty work is concerned, if you are worried about jeopardizing your warranty, don't modify your car.

007 Abarth
09-29-2013, 11:13 PM
Are there any major aftermarket downpipes out there? I have searched everywhere and found none

mr_robs
09-30-2013, 09:25 AM
I guess it depends what your definition of "major" is (thats what she said).

Both TMC and Road Race make downpipes for our cars and in my eyes they are both very reputable tuners. Especially for a car that's relatively niche and has an aftermarket community that is still new.

elorablue
09-30-2013, 02:52 PM
Yes it does bring risks... To my lungs and all of those that share the planet with you. There is a reason we have these devices. I have no problem having a swap out with flanges for racing and track days, but when you are on the road please do the world a favor and keep your cat on. Better yet find a performance cat and get the best of both worlds.

+1