So a friend of mine with a '67 Le Mans is curious about computer controlled spark timing and I told him I think a 7730 could be set up on his car to control spark only.

I'm thinking if we can transplant Corvette TPI HEI guts into his HEI dizzy and then put on the appropriate sensors (TPS, MAP, MAT, CTS) and a wiring harness and ECM, we could do it. Am I correct? I wouldn't think the ECM would need to see the injectors in order to function, though I could be wrong.

 

While I am sure that it would work. At that point you might as well use a 7427 TBI truck PCM and run a 454 TBI unit on the car.

 

Yeah, but I don't think he's ready to go EFI just yet. But I'm working on him!

 

Yes, the '7730 could be used for spark only. There would need to be a lot of malf flags turned off, namely the O2, and there are others, that just aren't coming to me.

If you wanted spark ONLY, I would suggest the '7747, since the process to do so has been documented, check the FAQ sticky for a link to more info.

As suggested you could run a TBI set-up and still keep it looking like it is carburated. I plan to do this very thing with my Grandfather's '71 Chev pick-up, I finally convinced him. I plan to use a '7730 as an ECM, haven't decided on what bin to use, likely $8D, to keep it simple, since it's just a cruiser and it's N/A. I have thought about $59 for it, but the areas of the tables I will be using is in areas that haven't been expanded on.

It sounds like you are on the right track with the hardware. If the existing dizzy is magnetic, you can simply use that to trigger an ECM controlled ICM (7 pin), it doesn't need to be mounted inside the dizzy cap, it's just nice if you can. On my Datsun, if I decide to keep it dizzy, I will be using an ICM from an EFI 2.8L found in an S-series. These ICMs are small and have all the computer controlled connections that are needed.

You would likely want to add a Knock Sensor as well. This is where the '7730 would make for a cleaner install, in that the KS filter and related ESC is built in, where as the '7747 uses an external ESC.

 

The only problem you have is the 7730 won't run a dual barrel TBI properly. The 7427 will and is a much better ecm than the 7747. The 7427 also has the internal ESC setup. The 7427 is also more plentiful than the V8 version of the 7730.

 

What do you mean by it won't run properly?

What kind of problems would/could there be?

 

the 7427 would be the choice to go with. it will do pretty much everything the 7730 will do & more.
fan control is the only thing i can think of the 7427 can't do, or has that been taken care of now?

the 7730 8D runs 8 injectors mounted in the intake near the heads & fires them all at the same time.
don't hold me to this as i didn't look it back up, but i think it only fires the injectors once per crank revolution, or maybe its twice.
TBI alternately fires each of its 2 injector 4 times per crank revolution.
the TBI ECM has 2 injector drivers, the 7730 has 1.
if the 7730 code was modified to fire the 2 TBI injectors enough, i don't think the single injector driver in the 7730 would last very long firing 2 low resistance injectors.
then there is the problem of finding a good 7730 MEMCAL for a reasonable price.

 

Yes, the knock sensor too of course. The ability to auto-retard timing when necessary is one of the key things he's after.

Besides, I'm most familiar with the 7730 ECM than any other since I'm running one on my Camaro.


Guys, thanks for the info. Sounds like this is a viable project.

 

Isn't this where tuning, and adjusting the bin comes into play?

I have no worries about the injector driver(s), the final impedance ends up being the same or very close to the same between 2 Low impedance injectors vs 8 high impedance injectors.

I have a few '7730s (and a couple '7749s) and some MEMCALS kicking around, I'm not worried about hardware.