Re: New Engine Update (archive)

Thanks for the advice. I have replaced the fuel pressure regulator. The split second system allows for adjustment of the fuel mixture along with a fuel mixture gauge that mounts in the car. I have checked all the sensors and everything is within spec. But the mixture is definitely to rich on the low end and to lean on the high end. The mileage did not drop during track use. It stayed at 11mpg, while street driving yeilds 12mpg. Plus the engine will not spin up to 6000rpm. This could be the factory chip that I am using.
The Split Second system arrives on Weds and on Thursday the car goes on Autothority's dyno for the custom chip :-)

I am not very comfortable tweaking engines, I am much better at tweaking the chassis/brakes/suspension. All of the other systems on the car are working great. The car handles so well, my last driving instructor thought that we were running on race tires when I was using street tires. Few cars can turn and stop as well as mine. I just need somework with the go.

Where did you get a stroker crank for the 3.5? It sounds like your engine might be better set up for forced induction than mine.

--Justin

Justin,

Been following your posts with interest, I plan on doing the same mods to my motor, including the supercharger (I would like to collaborate on this). I don't think it's the air flow sensor though. If your engine is breathing better, the meter should still register the increased air flow and adjust the injection duration accordingly. If at WOT you are exceeding the air flow range of the meter, and have pegged the vane wide open, you would run lean because the engine thinks it is getting less air than it really is.

It seems you are way out of spec (farther than could be attributed to a custom chip) to temper your exhaust tips. Assuming you are using the stock injectors, I would look at your O2 sensor and for too high fuel pressure in the injector rail.

Good luck,

Tim

red 90 535iM (racing dynamics headers, stroker crank and rods, wiseco 95 mm forged pistons on deck pending further research)

For those who follow my sporadic postings, know that I have been installing a highly modified 3.5l into my 535 for the One Lap of America race. Well the race starts in less than two weeks and I have a couple things to figure out.

The installation went well. It took 3 days to remove the old engine and install the new engine. I will detail the entire process on my website in a couple weeks.
The engine started fine. She runs and definitely has more power. The big problem is the fuel mixture.
Baer and I have been trying to get a Split Second Mass Airflow Sensor from BMP, HMS, and Split Second for 5 weeks without any luck. This is a must for modified engines because the vane airflow meter cannot compensate for the extra air. Anyhow, the engine is running at full rich. I have been getting 11 to 12 mpg(easy driving). I removed the performance chip and reinstalled the factory chip to attempt to lean out the mixture.
So the engine now has 1000 miles and 1 driving school. The engine was running so rich at the driving school my tail-pipes are gold and blue! The engine pulls very strong, but without a performance chip lacks a good deal of horsepower.
On Thursday the car will be put on Autothority's dyno and have the chip configured custom for the car.
I am hoping for at least 300hp.

I will try to keep you guys informed on the results.
--Justin

Follow Ups:

Re: New Engine Update Tim Panczak 00:07 4/24/2001 (2)
- Re: New Engine Update Justin - RedFive 23:03 4/24/2001 (0)
- One more thought... Tim Panczak 13:16 4/24/2001 (0)

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