Quote Originally Posted by Vettepilot View Post
Separate question.

There's "I need a touch more "accelerator pump" and want to fatten up the midrange a touch."

Then there's "I'll adjust VE and change some Bins and tweak the trims."

I'm WAY in the first camp. Is that gonna fly??

Note: I'm not totally "cave man." I have a wideband AFR setup.

Vettepilot
Before Megasquirt existed, I met Bruce Bowling at a get together in Ohio. Bruce is a really sharp guy. We were talking about using tuning software. I told Bruce that the biggest hurdle for folks coming from the hotrod world was turning jet changes and accelerator pump shot into VE tables and AE duration. Tools that represent the hotrod way of tuning might be helpful... an "everywhere" fuel adjustment could represents jet changes, a dial for idle mixture, a choke spring tension adjustment for cold starts, a pair of accelerator pump sliders to tailor pump shot, would really help transition between mechanical things and digital bits. I'd even said that it would be really cool to be able to click on pictures of a digital carburetor and distributor to select the changes you want to make. I've never used MS but I believe their software has some of that functionality built in.

I came from the world of carburetors and distributors, and I started modifying EFI when people outside GM had very little clue how GM's software worked. We've had folks here in their '80s learning how to tune and swap efi bits successfully. I think you can get this. I wonder if coming from "I can do this easily with a carb" is going to be a big source of frustration? But maybe this is more like learning a new language. And the new language has more words to describe things so you will be able to understand what the engine wants much better.


So, how easy is it to burn your own chips?? The little reading I did on it made it seem rather daunting to get set up for that...

Then, converting OBD1 to being programmable. Again, over my head.
More detail to go with steveo's posts.

OBD1 is already programmable. Remember when we would tape over the small hole on the back of a cassette so we could put our music there instead of some craptistic band? This is the same thing. There's a chip inside the ecm that's programmed with lounge music. You can change the tune.

Tools you will need:
Eprom burner with software
Eprom eraser

You will also want a way to talk with the ecm to see how the engine is doing. The ecm is able to provide clues to what the engine wants and what it likes. You need software that can interpret the ecm's communication. Most folks use Tunerpro.

You will also want a tool to view and edit the data in the chip. Again, Tunerpro can do the job.

This is the bare minimum. Upgrades can include switching from EPROM to electronically erasable chips, adapters to allow quick and easy chip removal, and an emulator so you can make changes to your calibration while you're driving.

You have a '94 truck already? Automatic equipped trucks have a 7427 or similar ecm already. Those are a great choice for an EFI project. I agree with steveo. Start tuning the '94 to get used to the tools.