What am I doing wrong?
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Originally Posted by BlueShadow
I had a similar problem with CromePRO and my turbo B18C w/ P28 ECU. While I was tuning my AFR's from 26 in/hg to say 15in/hg would be 15:1. But when I was cruising around in really high vacuum it would read 11:1 or 12:1. But at that point my vacuum was higher then 26 in/hg. 26 in/hg was the highest vacuum column on my Crome fuel map. So I thought it had to do with my actual vacuum being out of the range of my Crome fuel maps highest vacuum column.
Maybe if you rescale the vacuum columns so that the first vacuum column is 28 in/hg or 30 in/hg you can actually log and adjust the AFRs for the really high vacuum columns? I haven't gotten a chance to experiment with scaling vacuum columns in CromePRO yet to see if it will work. But maybe you should give it a try.
Look at your vacuum gauge and when it starts reading rich when you are in high vacuum make a note of what your vacuum gauge reads. Now look at your fuel map and compare that with your highest vacuum column. Post up what your vacuum & AFR numbers while actually driving and your highest in UD.
Maybe if you rescale the vacuum columns so that the first vacuum column is 28 in/hg or 30 in/hg you can actually log and adjust the AFRs for the really high vacuum columns? I haven't gotten a chance to experiment with scaling vacuum columns in CromePRO yet to see if it will work. But maybe you should give it a try.
Look at your vacuum gauge and when it starts reading rich when you are in high vacuum make a note of what your vacuum gauge reads. Now look at your fuel map and compare that with your highest vacuum column. Post up what your vacuum & AFR numbers while actually driving and your highest in UD.
The problem with that is that it runs rich everywhere, not just in vacuum. I will do everything I can to get this working in a few weeks since I have to pass smog with what I have on there now: blue box.
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From: Colorado
Originally Posted by flatliner
Actually the air temp can scramble a base pattern, I know as I use resistors (yes i am cheap) when I race depending on the weather and temp. cooler days need less fuel. even 5 deg farenheit can make a difference in base settings of an easy 20hp on a tuned system. you need to optimize for different weather patterns and reprogram your rig on race day to those patterns.
Also, you actually need more fuel with cooler air. Cooler air is more dense, which means you need more fuel to compensate for the additional air.