I'm trying to tune my twin turbocharged 87 tpi with a prominator in a 165 computer. the problem I am having is around cruising speed. If im driving down the road at a constant speed and want to speed up, giving it about 15% throttle, the afr goes for 14s to 9-10s. it stays at that afr from about 10lbs of vac to 0. when I go into boost im setting between 11.9-12.5. which is what I want. I just gotta fix that middle part without messing up the top end. Any ideas????

Oh, i'm useing tuner pro RT.

 

here is the bin im using. I trying to pull some fuel out on the maf table but it didnt really change anything.

 

Well, at 2800 rpm, you're commanding a PE target AFR of 9.66:1 and you're entering PE above 19.92% throttle. I'd say that this fits your description of what is happening at part throttle.

At higher rpm your PE target AFR goes to 7.19:1.

Warning: PE targets richer than approximately 11:1, will not result in any increase in fueling without some special changes. The bpw will be limited. You will likely run lean once you peg the MAF. Proceed with caution.

Also 30lb injectors may be a bit small for the task at hand. How much boost and rpm are we talking here.

 

Im running 42lb injectors and 7lb boost at 2200. The motors red line is 4000. I know the PE table shows that but It does seem to be effecting the motor when I change it?!? When we had it on the dyno the only thing that would effect it was changing the inj constant. thats why it says 30lb. under wot I have the afr I need. Its just that middle part. and I did notice that it isnt happeneing at a certain rpm. it seems to happen only under light load.

 

Ok, oversize injectors relative to the injector constant will help, but the bpw will still be limited albeit at a longer pw when the limitation occurs.

This limitation is also airflow dependent, so at lower MAF readings, you may not encounter it, so you do run the risk of going very rich. At high MAF readings you certainly will, that's why the injector constant change is helping to provide enrichment at WOT.

There are better ways to go about this. Shoot me a pm if you want to discuss some options.

 

sorry I dont know what a pm is. But if I understand you right, your saying to lower the maf table in the area that I go rich. dosent the maf table have to gradually flow upward through all the tables?

 

pm is short for private message.

I'm not suggesting that you should reduce the MAF tables where you're rich to compensate.