87 s10 2.8 with e85

[sbc350]

Hello. I'm currently learning about the GM ecu tuning. I converted my '87 2.8 v6 5sp blazer to work with e85 fuel. I installed 4.3 throttle body
to get bigger injectors. Also disabled the stock fuel pressure regulator and installed new one in the return line. The truck is running OK when
it warms up but bogs when accelerating(winaldl shows lean). So I need to tune the accel enrichment. Also it might need more fuel during
cold start since it needs to crank long time to get it fired up.

I think the ecu is 8062 / ACJA. I found few bin files here in the forum but not the exact file. I know the bin file is the one in the chip but
what are the other files for? For the tuning software? Why is the 8062 "$4e" ?
I installed the tunerpro, opened the ACJC 88 S-truck 2.8TBIHO 5 speed california.BIN file and found the things I need to change. I've been playing around with megasquirt before so I know the basics of ve tables etc..

[1project2many]

Welcome. Sounds like a practical way to approach your conversion. Did you have to make any changes to fit the larger throttle body on the 2.8 intake manifold?

$4E is a code that identifies a family of calibrations. As a general rule, the location in the file where each variable or table is found will be the same for all calibrations of the same family (or Mask ID) Any tuning software that can read one $4E calibration can read all. If that ecm was only used in one application it's possible there's only one mask ID available for it.

GM often made multiple calibrations for the same vehicle or for similar vehicles. Manual trans vs auto, one gear ratio vs another, California emissions vs Federal, A/C vs Non-A/C, etc. And sometimes there are several different calibrations for exactly the same set of equipment. I used to try all the appropriate calibrations to see which one worked best then use that as a baseline for my tuning.

Happy tuning.

[sbc350]

Welcome. Sounds like a practical way to approach your conversion. Did you have to make any changes to fit the larger throttle body on the 2.8 intake manifold?

$4E is a code that identifies a family of calibrations. As a general rule, the location in the file where each variable or table is found will be the same for all calibrations of the same family (or Mask ID) Any tuning software that can read one $4E calibration can read all. If that ecm was only used in one application it's possible there's only one mask ID available for it.

GM often made multiple calibrations for the same vehicle or for similar vehicles. Manual trans vs auto, one gear ratio vs another, California emissions vs Federal, A/C vs Non-A/C, etc. And sometimes there are several different calibrations for exactly the same set of equipment. I used to try all the appropriate calibrations to see which one worked best then use that as a baseline for my tuning.

Happy tuning.

Thanks for the info!
The 4.3 body is a bolt on, but you need to enlarge the intake manifold holes a bit.







Laser cut block off plate for the pressure regulator:





I can borrow my friends eprom programmer to get things started. I wish I had the ostrich to make live adjustments
but I believe since it's working pretty well I can get the few things corrected by burning a chip and then testing it..

[RobertISaar]

is there a specific reason you're running E85?

the 2.8 doesn't run nearly enough compression to have a real advantage from its use.

[sbc350]

is there a specific reason you're running E85?

the 2.8 doesn't run nearly enough compression to have a real advantage from its use.

Yeah it's the gasoline price here in finland. I save 0.3-0.4e / liter when driving with e85.
The engine has 257k miles on it but runs great tho. But if it ever needs overhauling I will
update the compression to have advantage over e85

[sbc350]

I painted the car, changed the clutch, driveshafts, made custom bumbers etc. Now is time to start the ecu tune finally.








I tried to connect the pocket romulator to the ecu but the connector has 28 pins and chip is 24. So I need somekind of adapter? I found this, sounds good if I could make 2 programs for gasoline / e85: http://www.moates.net/g2x-tbitype-sw...pter-p-86.html
Has anyone tried this?

[sbc350]

Bought this china eprom programmer and managed to program a chip with the .bin I downloaded. The car starts and runs with it but seems to run richer than with the stock chip. The stock chip is ACJA and the .bin is from ACJC. Both are with manual transmission etc.
I tried to read the stock chip, everything seemed ok but when I opened the file in tunerpro the fuel table and spark table are empty. Almost all the other settings are 0 too. Some random data is there. Any Idea why? Tried to read the chip again and the result was the same. It would be easier to start the stock tune since it's really close, all I need to do is to tweak few things to make it perfect..

[sbc350]

I got the data from the original chip. I had the voltage set too high..

[sbc350]

"Async pulse coming out of DFCO" Is this extra fuel injected when the fuel cut is coming back to fuel at low rpm? Having stall problems while decelerating and pushing the clutch, engine will stall. I have set the Async pulse to 15ms but it doesnt help, more?

[RobertISaar]

that is the correct usage of that item. it's possible you need less fuel, 15mS is a rather large burst of fuel, especially at low load, might be enough to not fire reliably.

then again, with E85..... you might need significantly more than what an engine running gasoline would need.

[sbc350]

Yeah it needed more, 28ms did the trick!

edit: I figured it needed more since the start point was zero..

[billygraves]

Nice Truck

[sbc350]

I'm using redline e85 additive to keep the injectors and fuel pump alive, been good for 10k miles now. Drove the whole last winter too, I use electric engine heater at home and work so the engine is about +20c when starting and it starts fine. Haven't noticed any ethanol in oil neither. I also modded the warm air valve to keep it sucking warm air from the top of the exhaust manifold to the air cleaner all times expect full throttle. The engine warms up to the point when thermostat opens just like with gasoline, maybe a lil bit slower tho. The stock old fuel tank started to leak under the band which keeps it in place. Planning to buy a new one or weld one out of stainless steel. Gonna replace all the hoses and filters too before they give up :)

I have to keep the stock engine because of the regulations, or at least I have to mask the bigger engine with the tbi intake to look like the stock 2.8 :)

[sbc350]

Does anyone know where I can find the BPC setting in the 4e?
edit:

Found the minimum BPW, minimum Async BPW and maximum Async BPW, how does these settings work?
Trying to figure out how to modify the stock tune for bigger injectors to run gasoline..