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Old 01-03-2001, 04:34 AM   #7
Scooby Specialist
Member#: 730
Join Date: Jan 2000

Stranger, it will be a single turbo setup, since twin turbo's on an EJ25 are basically a waste of money, and would be a nightmare to install and tune properly.

The turbo is a Garrett, IIRC, with a watercooled center bearing. The plumbing and such will pretty much look like many of the other Sube turbo kits. There're only so many ways to mount a turbo on these cars and have them fit the confines of the engine bay.

The real trick part of this kit is the Motec and the maps that Leading Edge and Rally Knight have developed for it over the past couple of years for street driven cars. (that's when Jon Ryther began work with LE on the rally cars.)


Imprezer, lay down the bong.

Tuning on the dyno is the most reliable way to test the effects of a modification. You're overlooking the fact that in the dyno cell, you can control the environment the engine sees. You can change one variable at a time to test the results without having to worry about other environmental factors affecting your data. You can simulate most any condition that the engine will see in an engine bay in the dyno cell.

I guess John Lingenfelter and Reeves Callaway are rank amatuers, since they dyno tune their engines extensively before they sell them to the end customer.

I guess Smokey Yunick won so many races and titles because he was lucky, not because he dyno'd his engines to get the most out of them. Even though, to paraphrase his words, the dyno is the most important tool in his shop to build high output engines.

Sure, the 3 examples above also track test their cars extensively, but to say "good luck driving a perfectly dyno tuned engine" like it's tuned for perfect conditions only is ludicrous. A dyno allows you to experiment with intake and exhaust combinations without the hassle of yanking the engine to make a minor adjustment. You also don't have to deal with trying to calculate drivetrain loss. I do agree with Shiv that until one starts making an obscene amount of torque and HP that drivetrain loss is fixed, not a set percentage of your engine's torque output, it's still an imprecise way to gauge the engine's true output. So many variables change from run to run... The trans may have cooled down a bit, and will give slightly different numbers from run to run, hence making measurement of an adjustment or a new modification all that more difficult and ambiguous.

Did my tweek hurt the performance, or is the transmission cooler/hotter than the last run?

I still don't know a whole lot about LE, but what I do know is they're a very big name in the sand rail and sand dragster community, and they've been playing the turbo Subaru game a lot longer than most of their domestic contemporaries, on the order of 15 years or more, IIRC. Who else on this board can claim that breadth and depth of experience building hi output Subaru engines? Cobb Tuning and Vishnu Performance, as good as they are, are in their infancies in comparison.

If you want to bring up the arguement that dyno numbers are largely useless and that 1/4 mile and 0-60 times are the true measurement of a modification, you have a very limited point. They're useful tools, but, as Shiv is so fond of pointing out, often have more to do with the driver than the modification.

You'll note, I did *NOT* claim that this would make me capable of hunting down Corvettes, Porsche 911 Turbos, etcetera. That is where it becomes a matter of the driver being the limiting factor in the performance equation. I fully believe that when the car is done, and broken in, that, in the hands of a skilled driver, it WILL be capable of embarassing a lot of high dollar machines. Maybe not with me at the wheel, but from a numbers standpoint, yes.

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