Yep please post the dyno plots.

[quote]Originally posted by David K.:
<strong>
I have the dyno charts if any one is interested.

David K.</strong><hr></blockquote>

 

Cyntex sees stock 964's with 190-200 hp on "HIS" Dyno set up. Other Dyno's maybe get Different reading. But he can repeat his readings. So just look at the increase delta of ~40HP over stock.


Mass Flow System, Cat By-pass Pipe, Stock Rear Muffler, Open air Box with K&N Filter, Dyno Tuned Chip By Cyntex


Mass Flow System, S-Car-Go Header 1 3/4" Dia x 26" long, Fabspeed Duel Inlet & outlet Muffler, Open air Box with K&N Filter, Adj. Fuel Pressure Regulator Set to 7 PSI over Stock Setting, Dyno Tuned Chip By Cyntex

 

David,

Have your performance numbers been corrected for gearing?

A while back we did an entire thread on perceived vs. actual HP gains.

Did you have your car dyno'd before the mods? What were the numbers?

FWIW, my RS America dyno'd at 242 HP at the rear wheels, done in 4th gear. I don't have the gear ratio for 4th gear handy, but divide 242 by the gear ratio to determine actual HP at the wheels.
All I had on the car at the time was a chip, not dyno tuned.

 

[quote]Originally posted by Rich W:
<strong>David,

Have your performance numbers been corrected for gearing?

Did you have your car dyno'd before the mods? What were the numbers?

</strong><hr></blockquote>

I do not think any correction factors were used except the weather station info. I am not sure what gear was run. The car was never dyno'ed in the stock configuration. The only goal after each mod was to tune the car for max HP and Torque across the whole rpm range.

All I know is that my car weights with a full cage, 1/2 tank of gas the spare tire in and with a lot of stuff removed is 2800 lbs and is much fasted then a stock Euro 964 Cupcar which weights ~2500 to 2600lbs.

David

 

Gear ratio for 4th gear is 1.086. Rich, does that mean you only have 222 HP after chiping?

 

David K, don't sell your driving abilities short. Many times it is the driver, not the car, which makes the greatest difference.

Chris K, ...YES! Bear in mind that's 222 HP at the rear wheels. Using a 15% power train loss, that translates to 262 flywheel HP.

 

[quote]Originally posted by Rich W:
<strong>David K, don't sell your driving abilities short. Many times it is the driver, not the car, which makes the greatest difference.

</strong><hr></blockquote>


The driver of the CupCar is one of the faster PCA Club Racers. He can kick my A_S all day long.

 

Well, I had my day at the track with my new "Cat Killer"...THREE days to be exact.

I just returned from Carolina Motorsports Park in Kershaw, S.C. - had a blast.

I must say, the car certainly felt as if it was "breathing" better...it really hauled down the short straights, could only get fourth gear though...still, a fun track. I'm pretty sure I haven't lost any low end, but the performance "pick up" I sense in the upper RPM range.

All in all, I'm going to go ahead and keep the European Premuffler installed, I like it. The only thing I don't like is that it seems I'm going to have to get the car "hammer tuned" or the like as it seems to produce a noxious exhaust smell and smokes a bit out of the tailpipe...I noticed this immediately upon installing the Premuffler - but thought the DME would adjust to it. I've got over 500 miles on the car, including 3 track days (247 miles) and it still seems to smoke a bit, indicating a rich mixture.

Although it runs nicely, what I'm experiencing with the smell seems to concur with a piece of advice given earlier in this post that I would need it dyno-tuned, etc. for optimum performance.

So, after three days of pounding the car on the track...all seems well - wish I could say the same for my brake pads/rotors and tires!!

***anyone who saw my "send me your used rotors" post?? I will be updating that as I used a set of "recycled" front rotors for this past weekend, they were free, I had them turned to give my new set of racing pads a good run in...that cost me $10 - was it worth it? Check the post and see.***

 

I am wondering...Is it possible, either by a small amount of futzing around, or directly to use headers such as the B&B headers for the C2, and retain the catalytic? I'm a bit against removing something that contributes to environmental health, and there is no way I'll pass smog anyway.

Will running headers such as the B&B be just a waste of time and $$ if you have to retain the CAT (other than weight savings)?

Thanks,
Jon

 

It would be pretty darned pricey, not to mention fairly heavy to retain the use of catalytic converters with a B&B header setup...you would have to have two cats.

I'm not sure if B&B does offer a catalytic setup for the C2 with their headers but I know GHL does, I've seen the setup, someone had posted a pic from a trade show in Vegas awhile back...it was priced over $2000.

 

To those interested, i just got work from B&B that they do offer a system for the 964 that can incorporate what they call a free-flowing CAT tip between the headers and their muffler. Sounds interesting....
price for the whole system (headers, one muffler with 3" tip and the Cat tip is around $2600.

 

Jeff,

I too had a cat bypass installed on my car. The smell just annoyed me to no end and I finally elected to pull it off and put the cat back on. I am not sure that you can tune the fumes out, I seem to think that the cat actually scrubs the exhaust clean otherwise there would be no use for it. But if you find a way to tune it - I'm interested in hearing your results.

I didn't notice any hp gains with it out - and I used a GTech Pro to measure 0-60 and hp. So I decided to follow this advice:

brain cells are more important than 0 hp

As a side note, my car was running a fabspeed chip w/exh, primary muffler bypass, and the powerhaus air intake. So no hp difference with or without the cat.

Cheers,

Boris Teksler

 

Interesting findings Boris...I do dislike the smell and wonder if I'm killing brain cells!?

Jon, I've owned the B&B "cat tip" setup...the converter doesn't go between their headers and muffler, it is actually incorporated into their adjustable tip...which doesn't work very well by the way. There is so much heat caused from the restriction that it melts the nylok (or whatever it is) nuts on the clamps and the tips lose their adjustment, causing other problems...mine actually fell off once...thank God the car was parked and I noticed it! <img src="graemlins/cussing.gif" border="0" alt="[grrrrrrr]" />

I would rather spend my money on the GHL design myself, it is rather impressive...the trade show I saw pictures from was the SEMA show in Vegas...somebody had posted a pic on here, I'll try to find it.

 

Hi Jeff thanks for that bit of valuable info. I was thinking pretty hard about it. I went to GHL's website, and they only show header systems for the turbo 3.3. Did you see a system for the 964 3.6? I wonder if it never got out of design since there is no mention of it on their website.

Jon

 

I did a search on "GHL" last night on the 964 board, I believe it was Randall Granas that took the pics and either sent them to me or posted them...I'll look into it a bit more and post the pic if I find it.

Randall, are you out there? If so, post the pic!