BackInBlackGP

Hi. Should I have no problems reading my Hypertech PROM, changing the cooling fan parameters and re-writing the code back to a new 27C128 PROM?

I have the "Thermal-Master" track chip, which leaves my cooling fan running all the time... I would like to have the fan turn on at around 170° instead... I have a 180° thermostat (required ro use with this version of the Hypertec chip).

I'm assuming the $32 mask is compatible with the Hypertech, since it is supposed to be compatible with my original PROM from GM.

Any thoughts? Thanks!

BackInBlackGP

Anyone have a good compatibility cross reference for the 7165, 6870 and 7302 ECM's?

Grumpy

Start with a known good bin and go from there.
The aftermarket chips in general are just a waste of time to even work with.

Grumpy

7165 uses memcal and is a P4 series of ecm.

6870 uses a 2732 prom, and is the early C3 series of ecm, used in the 85 F Bods.

302 was a v6 ecm C3 as I recall, again 2732.

ULTM8Z

As far as the fan on/off temperature, I usually like to set it to about 10° over the thermostat temperature. Basically, let the thermostat do it's job. If it can't maintain it's specified temperature, the cooling fans are there to help. Otherwise, you're simply throwing horsepower away by having more load on the alternator for the engine to overcome. Also, running an engine colder than 180°F is very thermaly inefficient.

BackInBlackGP

Right! I have the 180° t-stat and I would like to set the temperature appropriately. Currently the Hypertech code runs the cooling fan ALL the time... I feel this is what might be killing my alternators every 1500 miles...

I agree with the fact that approx 182°F is the ideal operating temperature for an internal combustion gasoline engine... People will argue this to death, stating that 160° is better-blah-blah-blah, but let's not go there right now...

I will be reading the PROMs tomorrow...

AlexJH

The GM ECM page at www.diy-efi.org has a list, it's displayed by ECM and their applications.

Ed Maher

Right on. Running a fan temp lower than the stat makes no sense at all.

And the hypertech and other chips are truly a waste of time. Look at this https://www.thirdgen.org/techbb2/sho...hreadid=104792 for an example of why.

ULTM8Z

It actually gauls me that after so many years they can still sell these worthless chips for so much money. They recouped their "R&D" years ago and the parts cost all of about $4, yet they sell these things for, what, $150? Unbelievable.

Like you, Ed, I got my hands on a Hypercrap 92 TPI 350 chip and took a look at it. They did even less than the 305 in your post. The main fuel/spark tables were untouched and they only altered the WOT fuel/spark tables a little and changed the cooling fan temp on/off. What a waste.

BackInBlackGP

Well... Here's my first wrench in the gears...

Tried reading the stock Delco PROM today... No go. The reader did not even acknowledge it's existance. I had several other PROMs working today in the reader, so the reader is not malfunctioning. I know they can be finicky sometimes...

Any thoughts?

BackInBlackGP

Here's the reader... It's a "Sunshine"!!!

BackInBlackGP

Nobody wants to field this one?

Grumpy

What's the guestion?
HNU is a 86 2.8 5 spd bin.
2732 chip

ULTM8Z

Hmm... all I can suggest is double check your software installation, your connections, and that you're putting the chip in the ZIF correctly (with the notch facing the correct direction).

I'm running a ROMMAX chip reader/burner, so I'm fairly unfamiliar with this Sunshine thing.

BackInBlackGP

Grumpy: The Q is, why can I not read the Delco PROM.

Pro-Tour: The reader is in 100% functional condition. We use it at work to burn code for our machines. (And, yes, I'm inserting the chip correclty... )