Anyone with sport cat, 965 experience?

steven c · 12-04-2009, 06:02 AM

I am considering a 100 or 200 cell sport cat for my 91 965 instead of a cat bypass. I realize it will not make the same amount of power but for the next 2 years I will not be changing the cat and bypass once a year either. Once the car hits 20 years old here in Texas no more tests! I also do not want the car too loud so my wife will continue to like going out in it so might have to add a muffler back to it as it currently has a muffler bypass.

It seems the Cargraphic 100 cell is the most expensive and then there are a few 200 cell units out there. Any thoughts or suggestions appreciated!

Black_Hat · 12-04-2009, 06:21 AM

I live in Austin with a 1991 C2 turbo I have no cat and a B&B gutted muffler
My 02 is plugged in and my car has passed Austins 2 speed emissions test 3 years in a row.
I do it in Aug when it is 100 degrees .

sorry not the answer to your question but I pass with a good margin every time .

WPOZZZ · 12-04-2009, 12:51 PM

I have a cat bypass with stock exhaust on my 964 turbo and it just has a slight low rumble.

steven c · 12-04-2009, 05:59 PM

Bryan, do you have emission testing way out there? If it will pass I will go that way but I have a friend who said his would not?

Ronnie's.930 · 12-04-2009, 06:53 PM

The emissions "cut off date" in the DFW area of Texas is actually 24 years (my 87 930 was tested last summer) . . . unless something has changed?

WPOZZZ · 12-04-2009, 07:27 PM

Quote:

Originally Posted by steven c

Bryan, do you have emission testing way out there? If it will pass I will go that way but I have a friend who said his would not?

No emissions testing here.

89turbocabmike · 12-04-2009, 09:22 PM

Steve, if you want to reliably pass smog I would suggest at least a very high quality metal matrix 200 cell cat. I would guess that Cargraphic is probably utilizing a HJS metal cat. If so, they are a very good cat, and never inexpensive. For the most part with high quality high flow cats, you get what you pay for. More catalytic material means that cat will last a long time and handle heavy loads. Metal matrix(what I think all OEMs now use) are better than the old ceramic style. HJS makes some of the best and are popular with many high end exhaust fabricators. Whatever you buy, make sure you know what brand of cat is.

steven c · 12-05-2009, 04:00 AM

Mike, very helpful and yes I have 2 options with a HJS cat. 1 100 cell and the other a 200 cell.

Ronnie, it was 20 years forever...may have changed. Will ask today. Thanks

911st · 12-07-2009, 07:52 PM

Is it not cheaper to have someone put the stock cat back on two times until you are not subject to testing than buying a race cat and installing it.

That is one install compared to to installs and two removals. Plus you will make more power with less lag. Turbos do not like back pressure at all.

The C2T final muffler is a great turbo muffler and a tennis ball will pass through it. It is just the pre-muffler cat that is restrictive.

Another option is to a final muffler bypass and keep the stock pre muffler cat.

Lastly, you could have the pre muffler part of the stock cat gutted but I do not know if it will help much.

911nut · 911nut's Garage

Quote:

Originally Posted by 911st

The C2T final muffler is a great turbo muffler and a tennis ball will pass through it. It is just the pre-muffler cat that is restrictive.

Keith, I think we've all seen the Fabspeed video where they cut the stock suitcase muffler open and sing it's praises, but it has too many turns in it to be truly "low restriction".
Damn thing weighs 25 lb too.
I replaced my bypass and stock muffler with a RarlyL8 muffler two years ago, Saved 42 lb off the tail of the car and could feel the difference with the butt dyno.
I'd use the suitcase muffler only for it's "civilized" sound.

911st · 12-08-2009, 04:58 PM

Cool Paul.

I suspect the Cargraphic stuff is great. The also used to have a tunner kit for the C2T's that came w the exhaust and took over control of the WUR control pressure, BOV, WG boost by rpm, timing... and had real time wide band O2 correction of AFR's. Big bucks and nothing like anything anyone else has seen on a CIS Turbo motor. However, it was about a $5k investment some 7 yeara ago plus dyno work to dial it it.

Speedy Squirrel · Speedy Squirrel's Garage

100 CPI will get the job done, and the backpressure is quite a bit smaller than the stock 965. That is plenty of surface area for the warmed-up vehicle testing that most states do. Just don't buy the cheapest one, as that usually means they have the lowest precious metal content. A ceramic substrate is better for our needs than metal.

steven c · 12-08-2009, 06:46 PM

A lot of good advice..thanks! I am the one to swap the cat bypass every year and I already know the name of that tune. So in the spirit of not getting mad at myself I will go the middle route. Cargraphic is the way I plan to go. Now their full tuning kit sounds very interesting as a big time budget buster...probably good I have not seen that! Thanks everyone.