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Lorenfb Lorenfb is offline
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Join Date: May 2003
Location: Manhattan Beach, CA
Posts: 2,352
Reply to Jeremy which I posted on Rennlist:

Jack:

It would have been better to have had a tabular data output to make comparisons.
But that aside, the max torque is only 4.5 ft lbs over stock. The 4000 RPM torque
did come up about 10 ft lbs, though. This about 6+ HP.

Now, in evaluating the peak HP increase of 14.5 (RWHP & NOT cranK) you'll see
that it occurs above 6000 RPMs. This results from a little pickup in torque. The
question is, what's the true basis for this torque increase?

First, I think your 3.6 is not totally stock, i.e. you have a non-stock exhaust. Also,
there maybe other not stock things. So making a chip comparison on a non-stock
car and extrapolating that to a stock one is questionable. This is because once you
change an exhaust or intake system, the engine will need to be tweaked which
will potentially show more HP improvement than just a chip change on a stock
engine. You can see that much more fuel is being dumped at or near the peak
torque (AFR = 10 versus about 12 for stock) and max HP.

Bottomline:

The results seen could have also been achieved with an AFM tweaking. You still
have the stock AFM and not a MAF unit? What you're getting in HP gains is what
usually occurs and is not much different than the Bruce Anderson runs. If you review
that data, you'll find that the most HP gain was at around 6000 RPMs.

I was involved over 8 years ago with a number of shops, (You probably know which
ones.), installing and evaluating chips. Most of the shops have stopped installing
chips, especially on the 3.6 because of problems, e.g. idling and pinging.

So, for most stock engines and the way most Porsche owners drive, performance
chips in my view are of questionable value. This outlook is based on a purely objective
evaluation over the years. For many, though, installing a perfomance chip may be
worthwhile from a subjective point or track racing at or near 6000 RPMs.

Another point: Can some of you guys make intelligent comments like the few
who do and not always "trash talk". Come on now!
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Loren
Systems Consulting
Automotive Electronics

'88 911 3.2
'04 GSXR1000
'01 Ducati 996
'03 BMW BCR - Gone
Old 01-23-2004, 08:46 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #107 (permalink)