Fine Tuning a 360 Magnum with a Brawler "Double Pumper"

jmanhoff said

Okay I was actually sort of pointing at asking this question. I understand the concept of changing IFRs and IABs to get the right “mixture” but didn’t know what the ideal number of turns was.

When I pull the carb off tomorrow I’m going to “reset” it, so square t slot, I’m going to verify the number of turns for the curb idle until it’s at the right exposure, and then going to probably start the primary mixtures at 1 turn and secondaries all the way in.

Click to expand...

Go back in this thread (search may save time. LOL) and find the posts about setting the transfer slot as well as the one(s) that link to timing for a magnum 360.

I don't know what is 'right' for that carb. Nor do I beleive anyone here knows. What we do know is there is a range in which the idle throttle position will have a working relationship that provides off-idle AFR to where it can be trimmed with the idle screws, and then if needed some IAB or IAB/IFR adjustment.
If the t-slot is too wide or too long, it can be shortened up as Aquartlow posted on the racingfuelsystems forum (version that is now tapatalk). It also may need tightening up using a t-slot restriction.

This is all an iterative process. If you have a leaner than ideal fuel mix, then it will likely do better by lighting it off sooner. Change the fuel mix at a given condition and the timing required to develop the most pressure and force will change. Get the timing curves in the window that was established by Chrysler and Mopar Performance and there will be less iterations until the gains are no longer noticable.