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Old 02-07-2005, 04:45 PM   #28
Kevin Thomas
Street Racing Instructor
Member#: 110
Join Date: Jul 1999
Location: 1997 OBS, 1996 SVX, 1988 RX
1989 1989 XT6


Car: 1989 2.7ltr Subaru XT6 (AWD/Autotranny)
Place: Xotic Motorsports
Dyno: Dynojet

Car has bad tranny. It's very weak. I can't describe some of the noises/shakes/shifts that come from that thing. So, I couldn't dyno in AWD. Ever since learning the tranny was weak, I've been dynoing this car in FWD mode (put 10 amp fuse in place in the engine bay). So all dyno runs that have been performed previously and up to now is in FWD mode.

All dynos are from the bottom of first gear and stopped when it shifts out of 3rd. I only show 3rd gear hp/torque results to prevent confusion. I do like knowing what's going on power wise in all gears though.

The dyno plot you'll be looking at is a comparison of 3 different dyno session.

The blue line stock dyno run.

The green line is when I had a 2.25" cat back exhaust put on with a 2.25" Dynomax Ultra Flow SS muffler.

The red line is the 2.25" catback with the addition of a JC Sports intake and a ProECM pulley added.

Max hp I now have is 120hp vs 113hp with the Dynomax muffler vs 112hp. This doesn't tell the whole tale of the tape. As power drops off with the stock setup, there is a fat gain with the intake/exhaust/pulley combo. I picked 5600rpm in the graph to demonstrate the difference in hp. Notice where at 5600rpm I have 120hp while stock I only had 100hp. That's great!

Torque graph!

I'm not going to speak about the max torque since the result is a bit skewed. When the car shifts from 2nd gear to 3rd gear, it's right at torque peak and a part of the shift shows up on the beginning of the graph. However, I picked the same point in this graph (5600rpm) as the hp graph to show the gains made. While stock the XT6 only made 93lb-ft of torque at 5600rpm, the intake/exhaust/pulley combo shows 112lb-ft of torque. That's a gain of 19lb-ft of torque. Nice! And it seems that it pretty much tries to keep this gain throughout the powerband.

So there you have it. If you plan on modifying your XT6, a 3" intake tube, a ProECM pulley (2lbs lighter than stock) and a 2.25" exhaust can really work for you as a combo together. Stock hp and torque figures are 145hp/156lb-ft or torque. So theoretically, you can say I'm making approximately 165hp/175lb-ft of torque.

More information on the mods I posted can be found in some of my other posts.
Dynomax muffler vs stock (Pics, Sounds, Dyno)

ProECM Pulley (Weight vs stock, color, etc) Page 3 of thread.

JC Sports Intake (On my other XT6, dyno vs stock, etc)
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