Time for a little tweak

[dwalker151]

As always I've got a question.



My early 91 doesn't seem to have much off the line. The thing is stock except for a opened exhaust system and a BHAF. I would like to gain a little bit of snap off the line without making anymore heat overall. Can I do it with the AFC screw??



ideas?



Thanks

Dean

 

[JLEONARD]

Dean,

I have an early 91 as well and recently made some tweaks that made a big change in performance.

I first turned in the AFC screw. That made only a minor difference. I was only able to turn it about 1/2 turn otherwise it made more smoke than I wanted.

I then turned the starwheel CW 1/2 turn and move the eccentric 90 degrees to just s little shy of max.

These made a big change in performance thruought the rpm range. The truck really pulls hard now.

I get a small shot of black smoke between 1000 and 1400 rpm or so, then it clears out pretty well.

EGTs overall are about the same, but they rise faster and take longer to cool before shut down.

Hope this helps.

Just keep track of what you do so you know where the adustments are.