GM Prom for zz4 conversion kit
 

Does anyboy know about the prom that GM was selling with there now discountinued street legal zz4 third gen conversion kit? I was thinking of buying it since i have a 350 now and it was designed to work with the q-jet.

They discontinued the HO Conversion Kit?

Didn't know that, but the PROMs were intended for use with the 1228079 ECM, which was also used on the last of the LG4/L69s.

I suppose I could read the image, and send out the .bin file if anyone needs. I have the non-ESC ZZ4 PROM out in the garage, still installed in the old ECM (I did the HO conversion kit several years ago, then later converted to EFI). I probably have the ESC-enabled PROM somewhere too, but I'm not sure exactly where I stashed it away.

Or, you can probably still order the PROMs from GM, even if they're no longer selling the entire kit.

Hey could you send that my way? What is the difference between the the esc and non esc chips, in the way of wiring? You just unhook the esc module or the knock sensor? Thanks in advanced.

bmmontess@aol.com

Well, I'd assumed I'd be able to read the PROM....but I've been unsuccessful so far. I'd assumed it'd be a 2716, or equivalent, but now I'm thinking it's some sort of Delco proprietary chip -- no window, perhaps was a one-time programmable? -- anyway, I haven't found any settings on the PP2 that will get it to read correctly.

FYI, this is the non-ESC ZZ4 chip, GM P/N 24502457.

Sticker says:
24502497
CAMPKG
CHK0D64

And underneath the sticker, printed on the actual chip:

Delco 519K 8229
2055 06630
CE 1024

Can anyone clue me in on how to successfully read one of these?

Basically. '82-'83 LG4's never had the ESC stuff, so the chip probably doesn't look for it. I'm not even sure you'd have to unhook anything.

Another guy I was sort of helping out, who also used the GM conversion kit, added the ESC circuitry to his. There wasn't much difference, IIRC. I think there was only one wire from the ESC module to the ECM, and a couple of wires (probably just the sensor, power, & ground, to install the ESC module itself)

The ESC-enabled version of the ZZ4 PROM is 24562456.

Computer confuse me. What is ESC? Do you think the addition of this PROM would be worth it? Dave, did you save parts of the conversion kit? I was thinking about adding certain parts to my car. Would you be willing to sell any of it if your not useing it any more.

ESC = Electronic Spark Control, i.e. Knock Retard.

Worth having, IMHO, for the occasional tank of bad gas. Running without it means you need to be extra careful to avoid detonation.

The computer stuff takes awhile, but keep at it, and it'll come.

If you're interested in the conversion kit parts, shoot me an email or PM.

email: hotrodder(at) mindspring.com

My car ran pretty decent with the ZZ4, and conversion kit stuff. Best ET and MPH was like 13.6 at 102, and it would do better than 20-22 MPG highway. Only downsides, with the carb was that cold weather driveability wasn't so good (not a problem for me, I grew up with carbs, but my wife would constantly stall the car when it wasn't warmed up), and when I moved to CA, not easily being able to edit the timing curve, to adjust for the lousy gasoline here.

I never ran the ZZ4 engine with any other PROM, so I can't really compare, but if you wanted to stay with the CCC Q-jet, I'd think that may well be the way to go, especially if you've got a somewhat similar cam, and/or aluminum heads.

Also, I would like to get these PROM images posted somewhere in the public domain, before selling them off.

Yes. The chip is a N82S181. You may read it by applying 5V to pin 18 externally and reading as if it were a 2732. I created a little adapter out of a socket by bending pin 18 up and jumpering it to VCC.

If you are able to read it I would like a copy.

HTH

John

Thanks! I'm quite certain I NEVER would have figured that out on my own. I'll give it a try this weekend, and see what happens.

Both the ESC and Non-ESC bins have been uploaded to the "stock binaries" section of

http://moates.net/fileman/index.php

Scroll to the bottom and look for the "ZZ4_CCC" filenames.

Thanks to John (32V DOHC) for reading them!

Could some one please open the esc bin and post the spark chart. I would do it but all I have is tunner cat $61 so I couldn't open it.