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Cat converter delete on a '86 944 NA

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Old 02-21-2011 | 08:46 PM
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Default Cat converter delete on a '86 944 NA

Yes I did a search but want to be sure.

Who here has deleted the cat con on this model and what were the results? Will keep the o2 sensor but am considering trashing the cat.

michael
Old 02-21-2011 | 08:54 PM
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I hear it gives you "theoretical horsepower" that you may not notice and a slightly raspier exhaust note that you will notice.
Old 02-21-2011 | 11:27 PM
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http://www.siliconeintakes.com/ FTW!!!

I just ordered one of these, but haven't installed it yet. It looks exactly like a CAT. Cheap too....
Old 02-22-2011 | 12:17 AM
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I'm running sans cat on my 85.5 NA, and I think it sounds a lot better than stock. This is with no other exhaust modifications. I'd be skeptical on any HP gains though...
Old 02-22-2011 | 12:25 AM
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does the area right by the tailpipe blacken up from carbon build up?
Old 02-22-2011 | 02:56 AM
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I just installed a header and test pipe. It sounds nice except that my muffler rattles a lot now. It seems to give a little boost in performance but that might just be because my cat was old and clogged or it could just be in my head.

One thing I found out with this new set up is that when I red line and let the engine wind down just enough while shifting it pops and shoots a flame out.
Old 02-22-2011 | 03:16 AM
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Originally Posted by m73m95
http://www.siliconeintakes.com/ FTW!!!

I just ordered one of these, but haven't installed it yet. It looks exactly like a CAT. Cheap too....
i love the description
Old 02-22-2011 | 03:29 AM
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It's not going to add much (or any) power, pollute the atmosphere, and be a pretty ghetto mod. A brand new high-flow cat is pretty cheap (less than $100) and flows amazing.
Old 02-22-2011 | 03:35 AM
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Originally Posted by FRporscheman
It's not going to add much (or any) power, pollute the atmosphere, and be a pretty ghetto mod. A brand new high-flow cat is pretty cheap (less than $100) and flows amazing.

It passes emissions... Who cares? You work for Green Peace?

The fake cat costs less than $50, shipped to my door. My car will still pass emissions. It WILL use less gas, which is what we all (drivers, and the EPA) want anyway. It will flow more than any cat on the market....period.
Old 02-22-2011 | 09:30 AM
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Originally Posted by F40LM
Yes I did a search but want to be sure.

Who here has deleted the cat con on this model and what were the results? Will keep the o2 sensor but am considering trashing the cat.

michael

You get more hp. Maybe 10 depending on the condition you cat right now. I know of one guy with before and after dyno runs gaining 8-10hp on a track car from a test pipe. Very good mod for a track car. Slight increase in sound levels, but with a stock muffler you would hardly notice. You can keep the O2 sensor and I suggest doing that even in a track car. It probably best to tune the AFM on dyno after you pull the cat to prevent lean running. As for on the street... well You are not going to gain enough power to notice.
Old 02-22-2011 | 12:43 PM
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Originally Posted by M758
As for on the street... well You are not going to gain enough power to notice.
I hear this argument constantly, and while I respect your experience and knowledge, I have to disagree.

Having such low power figures to begin with has made me hypersensitive to changes in power. I feel differences based on how cold the air is outside, and with minor (+/-1000ft) altitude changes. It may not make a difference on a track, but I sure notice those small changes.
Old 02-22-2011 | 04:52 PM
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Originally Posted by elzergone
I hear this argument constantly, and while I respect your experience and knowledge, I have to disagree.

Having such low power figures to begin with has made me hypersensitive to changes in power. I feel differences based on how cold the air is outside, and with minor (+/-1000ft) altitude changes. It may not make a difference on a track, but I sure notice those small changes.
All I said is don't expect a big noticeable change on the public roads. You will notice it at the track, but even then only when you are already tuned into the chassis. I think it is very worth while for a track only car. Not so sure about a street a driven car.
Old 02-22-2011 | 05:19 PM
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Originally Posted by m73m95

You work for Green Peace?

yes. as a matter of fact, he does.


Originally Posted by FRporscheman

I always use a catalyst because it's the responsible and considerate thing to do. Anyone who fouls the air we breathe just to gain marginal performance is an ***......

start with post 26 and enjoy the ride....

https://rennlist.com/forums/968-foru...e-968-a-2.html
Old 02-22-2011 | 10:26 PM
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Originally Posted by odurandina
yes. as a matter of fact, he does.





start with post 26 and enjoy the ride....

https://rennlist.com/forums/968-foru...e-968-a-2.html
Wow, I missed that thread the first time around. Kind of glad I did miss it now.
Old 02-23-2011 | 02:47 AM
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It is kind of funny reading that now. It was very early in my Rennlist membership and I was clueless on anyone having a "heated discussion", I thought it was just normal stuff.


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