FlyYellow

As promised the Dach X Sport Cats were installed & dyno tested. I've received Chris' clearance to go ahead and post my results.

Results: +8 Horsepower + 3.8 ft/lbs of torque

Observation: My Air Fuel Ratio changed a bit, which i would like some feedback on... so please post your thoughts.

Test: 1995 993 (non-varioram). Car was tested in the morning for the before and in the afternoon for after. The only change was the installation of the DACH X Sport Cats. Everything else was constant. Weather between morning and afternoon was mildly changed. Morning weather was 55 , Afternoon was 58 degrees.

Comments please......

Cheers,
Boris

jdistefa

Wait a minute.... Let me get this straight: Sounds better, lighter, AND objectively more power? Hmm. Could it be the holy grail of bolt-on exhaust stuff? Is Fabspeed watching this?

Boris - Thx for posting. I wonder how much better things could get with a little tuning on the dyno....

Bull

Looks good...better sound and weight at no expense in power. How many pulls were done each time the car was run on the dyno?

pcar964

Nice - I think that's the first time I've seen verifiable proof of a power increase for a 993 exhaust. Well done!!

Stephen Fisher

Why was the pull done in 3rd gear? I thought 4th or 5th was correct? I am not an expert at this.

SF

Bull

We usually do them in 4th gear, or most close to direct drive 1:1, with three pulls.

FlyYellow

Three pulls the best of each were taken. don't know why they chose 3rd gear, but as long as you apply the correct ratio correction it should be fine....

Bull

Excellent!

TroyN

I would think the a/f ratio would adjust as the computer learns its new configuration. However, I have bypasses and the car smells like it runs rich even after having them for a while.

Flying Finn

That's more due to the fact that some unburnt fuel or other crap gets through (that were previously "trapped" by cat). Some cars that didn't smoke at all start to smoke (burnt oil seeping through valve guides) a little after cat removal.

tj90

Boris: You took the best of 3 runs. If you look at the average of the 3 runs, is there really a difference or are we looking at outliers? Im trying to understand if there really is a statistically significant difference. Thanks for posting - i bet you like the new sound!

FlyYellow

no difference, i asked the same quetion they were all very consistent between one another.

that's actually the reason that i chose a dyno that bolts up to the rear wheel hubs vs a rolling dyno. i think the results tend to be very consistent.

tj90

Please clarify - no difference between each of the 3 runs OR no difference before and after the upgrade?

Can you feel the difference in the seat of your pants?

Thanks, TJ

pcar964

Thanks again for posting this Boris, you've answered a big question for many of us.

993inNC

Yes thanks Boris, thanks for re-insuring our feelings about the performance of our products. I have never even made an attempt to "over sell" what we do. This just shows that what we are doing works......Bill are you there? I appriciate the positive responses I get on a regular basis, and of course those of you that have trusted in us and spent your money with us......Thanks.

Okay, so first of the year we get another GB going? Who's with me JK'g