'88 302 ecu, LB8 2.8 V6 Maf.

I've got TunerCat + $3A tdf, and have started working on it...

There doesn't seem to be a constant for the pw of the injectors. Moving up to 36 pph injectors, and I want to change the fuel tables to compensate....

I'm looking at the injector pw vs load table - I'm pretty sure I can just scale that entire table for the injectors?

basically -

stock 13pph injectors = 3586 usec pw @ lv8 of 16 (LV8 = load value, yes?)
so in theory, 26pph injectors = 1793 usec pw @ lv8 of 16? Since I've got double the injector, I need half the pw (this is just a roughing in, and then comparing against an actual datalog)

Am I on the right track?

 

Or am I way off?

 

What you have posted is reasonable. If this ECM uses PW vs LV8 and has an injector opening time compensation table it should work out.

LV8 is Load Variable 8-bit.

Biggest problem is that there is very little knowledge about the inner workings of that ECM.

RBob.

 

That's fine. I'll just have to learn it, that's all.

Ok, is there a Max Air Flow vs RPM table in the '165 MAF ecu? I can't seem to come up with a reason for it, other than to notify the ecu if there is too much air being read for a given rpm (aka, bad maf)

 

Doward your gith on target with the pw vs lv8 table. as for the max airflow table youll need to get in contact with TC and have them add the scalars to your TDF. also for your turbo app a GN maf would work great if you put the GN maf tables into your MAF tables used a GN maf and used the GN max air flow table. Might even be a good idea to start with a GN timming table as well.

Most of those things will transfer with minimal headaches. if you need help with it email me scaling the injectors isnt that bad.

 

With Funstick bringing up a GN MAF, ever thought about switching to the Turbo GN ECM? Fully hac'd, entirely understood, lots of aftermarket goodies for it, can also run sequential injector with the addition of a cam sensor (w/o cam sensor will run batch).

Also used in the TTA. This ECM is the 1227148.

Just a thought. . .

RBob.

P.S. yes to the '165 and max airflow vs RPM table, it has it.

 

Perhaps.. but I feel if I'm going to swap around ecus, I'll go with a '749.

Just what purpose does the max air flow vs rpm table have?

 

The '749 is a good choice.

I think GM put that table to to inspire conversations such as this one. Or, just to drive us crazy. However, I do have some thoughts on it.

As you mentioned to cover for a bad MAF, I was also thinking that it is to prevent upward spikes in airflow. This would be caused by sudden throttle openings. The plenum would be rapidly filled with metered air that is not representative of the airflow into the cylinders. By capping the airflow term the fueling would be kept under control. In effect preventing a rich AFR burst that would wreak havoc with emissions and mileage.

In a thread here someone mentioned that GM implemented the airflow vs. RPM table to prevent modified engines from running properly. This was done on purpose to prevent modification of the engine.

RBob.