Speed density processor in a mass air car

[Guest]

[David Claflin]

Just to throw some follow up on this, after a loooong time. Ive been fiddling with this off and on, mostly off trying to get it to run better using the speed density processor I have. It's a DB1, that "looks" good on the circuit boards, but theres obviously no way to test it.
I tried running a mass air BAP sensor and while it would run, it idled high, and had other issues. I swapped in a MAP sensor from a speed density car, and that let it idle at normal RPM, but still was not quite right.
I noticed that at idle, cruise and WOT the trace on the volumetric efficiency table stayed right at 100%, which means it thought it was at WOT all the time, so no matter what I did with the rest of the table it always stayed maxed out. Mind you this is on a mild 306, that idles at 15-16" of vacuum.  I don't know yet, if there's something I did wrong, or need to change in the tune, or if there's something up with the processor.
I bought a 4 hole throttle body and modified a vic jr to run edelbrock fuel rails, so may mess with it more if I stumble across a known good DA1 or DB1 processor. I've got a JV1 processor that is from a 1986 AOD car, but I don't want to take a chance burning anything up on it. I've also got a complete car and EFI harness from a 1986GT, and a buddy has a stripped 1985 coupe, so they might all get thrown together on it to run a complete factory speed density EFI system and a 4 hole throttle body sometime in the future. If all else fails the Mega-Squirt systems seem to be pretty decent, may try one of those.

[mikestang]

Interesting thing here.  Were you using BE?  How was the data logging?  I was wanting to play around with a SD tune for once, (I have cal'ed many MAF cars) 

[85_GT]

Is there a logable payload for MAP?  What does the trace do in the spark tables?

[David Claflin]

Interesting thing here.  Were you using BE?  How was the data logging?  I was wanting to play around with a SD tune for once, (I have cal'ed many MAF cars)  

Yes, used Be with a CRY file from sailor bob. Data logging was OK, a few columns on there I had no idea what they were...LOL!

 

Is there a logable payload for MAP?  What does the trace do in the spark tables?

I don't remember looking at the spark trace, and MAP does have a column on the datalog
Here is a short datalog from the Bcam and Vic Jr., at WOT it's going to look really rich, but I was just trying to get the fuel injector duty cycle to align with that of the mass air set up. Don't have a wideband, so only way to compare.

[mikestang]

Thanks David. I have the file on Clint Garritys site. I see a .cry file but have not looked at it yet. In your file from Salir Bob, are there switches present to disable TAB and TAD? There are not in the file I have... that I can find.

[David Claflin]

There's the thermactor and egr present in the scalars, but nothing specifically identifying TAB and TAD.