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04-17-2001, 09:01 PM
Any words of advise on installing a test pipe in my 87 944 turbo for "track use!" I put the car on jack stands and looked at the location of some of the bolts, which look very challenging to reach. What tools will I need to successfully reach all the bolts, and what else needs to be removed to get the cat out. Any words of advise would be greatly appreciated.

Charlie R.
04-18-2001, 03:33 PM
I think people have tested the "test' pipes and in general they don't gain anything. The turbo is relying on back pressure to do its job.

If you want to install it anyway, it's not that difficult but you're right you might need a special wrench to get to some of the bolts on the exhaust flanges.

04-18-2001, 09:29 PM
Well, I was able to install my test pipe today. Took about 3 hours of standard wrench/grease work under the car. An 18 inch extension was required to reach the turbo down pipe bolts. The difference in performance is extremely noticable. The car feels much faster. As a matter of fact, its awesome!! Also the decibels have increased. I am 100 % satisfied with the purchase of the Huntley Racing test pipe. A perfect fit.

Charlie R.
04-19-2001, 11:50 AM
I've never heard such a glowing review for a test pipe. When I had my 944T race engines on the autothority dyno. I don't think the test pipe was worth anything. I do remember that we lost about 10 hp when we didn't have the muffler and exhaust system hooked up.

Charlie R.
04-19-2001, 11:56 AM
We did a bunch of testing w/ Supertrapps to try to make them work. Under no conditions were we ever able to make them NOT LOSE horsepower. Just a little tidbit since you may look at mufflers next.

04-19-2001, 08:23 PM
My test pipe is already hooked up to a B&B exhaust. The setup works well for me. By the way, don't you believe that the catalytic converter increases back pressure on the engine? To truly improve engine performance, you must decrease the intake and the exhaust restrictions. I just think of blowing through small straw versus a large tube. At the same pressure (turbocharger), the flow through the large tube would be much greater. The boost pressure is only a starting point, mass flow of fuel and air is the key to high performance. Correct me if I,m wrong.

Charlie R.
04-19-2001, 09:25 PM
You are right, but regardless of what everybody says about the factory they actually do their homework. Any engine builder worth his salt will tell you that backpressure is the key to horsepower. You want the exhaust gases to be sucked out not pushed out by the valve.

The straw analogy is true but a little to simplified for a modern Porsche engine. If it was a chevy w/ big carbs that's a different story.

I consider myself to be fairly unbiased. I used to bash the factory saying they do things to conservatively, etc. Then after a few years of racing I realized that they actually did know what they were doing. I had some pretty sharp guys telling me otherwise. But Dyno testing doesn't lie. Now looking back I feel like I was just a dumb kid thinking all adults were stupid. I guess we know how that one turns out.

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