Synch vs Asynch fueling

[EagleMark]

We already fixed the Corvair, he started with a fresh bin and idles great now. Besides a lot of things checked and unchecked wrong there was a lot of Items Not Defined, so I don't know what the issue was but it's good now.

I moved this to a seperate post for info.

I don't believe asynch is ever always on.

That was my thought, but I have V6 7747 bins that Async is always on, they run horrible so I took a V8 bin I knew was Sync and made it a 6 and they run great, this was on I6 conversions. I was wondering if there was a reason a V6 needed Async?

One of those bins (AKSF and AKSK) that runs Async always on is in ony's thread on Lean Cruise, it was a superceded bin and now that he has the updated bin he says it runs much better but I have not seen data yet to see if it is now Sync. I'm very curious...

[EagleMark]

Ony got the data from the updated bin and it's still Async all the time... just don't understand why they would do this on a 7747 V6 cal? The Corviar is running a 97427 V6 cal and it is Sync. Is there a change in V6 engines?

Then I remembered some? 7747 4.3L had 2 differant size injectors? That alone has always baffled me...

[1project2many]

I'm not sure what you're looking at. Which location? Which TP definition file? I've looked in TP and TC and I don't see a selection for what you're describing.

[EagleMark]

Well that is kind of the point, there is no parameter for this in $42! But in DATA there is a bit for Sync or Async under all switches. If it weren't for the TunerPro ADX file telling me fueling was Sync/Async I would never have known and continued to tune? Changing to a known Sync fueling bin cures all the issues. Seems every six cylinder bin (or at least all ones I've tried) is Async?

In $0D they run Sync and at WOT/PE or for some other reason goes Async. I think $42 does the same but it takes a lot more then a stock TBI engine...

[1project2many]

Well, that's a little different. I'll have to investigate a couple of different cals and the recorded data to see what's causing that.

[EagleMark]

Did a lot of reading today and going through hacks and bins... I just don't understand why any cal would be Async always from factory? It's not just V6 $42 either, there are some 7.4l and even $0D, $0E, $E6...

Some of the old DIY-EFI posts quote Async as firing every 12.5 Msec and has nothing to do with DRP, this would explain the accumulater/timer and saving some then dumping what's left if not used. Just sounds like a bad way to do things...

I'm now wondering if a couple rigs I tuned awhile back was a poor choice of starter bin/cal and not noticing this? Never had an issue with 5.7L stuff as I alwas start with ASDU, since then I have used it for everything. One's I had issues with were 7.4L and 4.3L, went back and looked and sure enough they were Async!!! I hate Async!!!

Because of all the research today $42 ended up with a few more paremeters, most importantly 2 BPW times, with these you can now spot an Async always bin... also filled in at least 100 descriptions in paremeters. All my notes from papers written, posts found and all my personal finds, it's like an EFI tuning dictionary now!

[JeepsAndGuns]

How can you tell a async only bin from a regular bin?