[s-cars] '93 UrS dyno results

[CaptMagu at aol.com]

Frank

As a point of reference, I thought Mance's car had an RS2 cam and head
porting. Not sure on this but that's what I remember. He had also done some
very sophisticated fuel tuning with a very expensive air fuel ratio
diagnostic tool. This along with the RC 310 cc @ 3.0 bar injectors and the
adjustable fuel pressure regulator were a reaction to frying his spark plug
electrodes.

The first place to start would be with the adjustable FPR. I also have that
fuel pressure guage to help me set things up. I've seen the ECU do a very
effective job of adapting to a wide range of fuel pressures as I've spent the
past year dialing in all the variables on my engine. One of the wierd things
was a boost leak in my I/C. This one was hard to find and a real mystery.
When I had the leak(it was leaking at the time we installed it) the car was
running very rich and the boost threshold was very high. I dialed the fuel
pressure down and was able to get the car to run very well with no
drivability issues whatsoever.. Did I mention that it had a very high boost
threshold(full boost at 4100 rpm)? Nobody that I know of had seen a turbo
this big run in one of these cars so when I was still able to get 28 lbs of
boost to redline we didn't suspect that we had a boost leak. I normally run
the boost control set to 22 lbs. The problem for the ECU here was that we
were getting a lot more metered air through the MAF than was actually
reaching the engine. With the I/C now fixed I've got the fuel pressure dialed
back up to 68 psi at idle without the vacuum line attached. So, why have I
rambled on here? To give you some encouragement to go ahead and add more fuel
with the adjustable FPR. Let the ECU do its job. If You're still not rich
enough you can always add the injectors later.

Good luck.

Hap, dialing my fuel pressure in Evergreen, Maguire