How do you tell if your prom is stock?

[ZR-1 Mack]

I'm pretty sure mine is stock, but the car does have a manual fan switch and remote access that are aftermarket so maybe the chip was also swapped out by the previous owner

Is there an easy way to tell if its stock ? I know the power key isn't bypassed but never thought to check until now.

[Kevin]

fan turn on, and CAGS are the most common changes

[WB9MCW]

take the unit off an turn it upside down and open the inspection lid and study it. Mine does a piggy back affair on top of the stock one, 90 degree to each other. because of the way the adapter fits in and the whole thing barely fits thru the portal. Now some chips are a complete repalcement so then the print on the chip will be ur telltail!!! let us know what u find. It is so great not having cags and esp. like having my fan come on at 180. my tunnel and under the hood temps are sooooooooo much better,, the stock 230 is nutz and was for the emissions testing...ur Z will be much happier at the new lower temps...ie mine on a 90 high humidty day will sit at 205 now after a 5 min stand still, now as i start moving again it will drop back to 180-185 while moving....much better..It's been sittin in my garage all last summer but I still plan to install the ...........................

http://www.c4orcecorvette.com/images/animation.gif

http://www.c4orcecorvette.com/images/zr1-black.jpg

http://www.c4orcecorvette.com/images/owner-cars/k-hastings-c4.jpg

http://www.c4orcecorvette.com/click here to go to BIG MOUTH AIR DAM SITE

[tomtom72]

Hi Mack, I think the only way to know for sure is to R & R the ECM so you can flip it over to remove the "door" that covers the PROM & it's easy to read the mfg's name on it without taking the PROM out.

It is just like a RAM stick only thicker & it goes in a slot on the M/B w/locks just like a Ram stick. You shouldn't have to remove it to see who made it. The backside facing you, after you take the four 7mm bolts off & the cover plate & gasket is off, will have the "program code" I.D. like ABYK for the updated GM code for the 90's. If you go to Marc Haibeck's site the list for all the GM I.D.'s for the OE/ PROMs are listed.

Hope this helps.

Tom

[WB9MCW]

good post TT. He should be able to figure it all out now!!!:thumbsup: :cheers:

[tomtom72]

Thanks Bryan! I'm just trying to carry on the tradition I learned from the senior guys about how we all help each other. Man, that's the best thing about owning one of these cars...the community is top notch!! The cars ain't so bad either:wink:

[ZR-1 Mack]

Thanks Bryan and Tom...will let you know what I find out right after Christmas. The car was an Arizona car so I think thats the reason for the manual switch.

But now I'm really curious because I never saw 230 last summer and was around 205-210 when standing still.

[WB9MCW]

my guess is that u got a mod chip already! Does the cags still function? cags is the 1-4 forced shift by solanoid activated shifting guide 1-4 gear for get this economy to make cafe etc. and avoid the gas g, tax! heywhatdidyathimk of the BIG MOUTH AIR DAM
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[bobbyhi]

I think they look pretty cool. Probably going to order one. Does anyone have one installed?

[RICHARD TILL]

I`m Glad Cags Was Explained. I Wondered What That Was But Didnt Want To Expose My Ignorance.

[ZR-1 Mack]

my guess is that u got a mod chip already! Does the cags still function? cags is the 1-4 forced shift by solanoid activated shifting guide 1-4 gear for get this economy to make cafe etc. and avoid the gas g, tax! heywhatdidyathimk of the BIG MOUTH AIR DAM
http://www.c4orcecorvette.com/images/animation.gif
Tom and Bryan thanks again for the info.

I couldn't wait any longer , so I opened up the ECM and sure enough the chip is a DELCO AXFK 0277. Gotta be stock. Probably will change it out this spring. Now I just gotta decide which one to get.

The CAGS must be disabled as I have the light on the dash but no limitations in shifting thru the gears from 1st to 4th.

Bryan I've seen the ones that go in the front license plate holder, but that design has gotta work alot better. Let us know how it works out on your car .

[tomtom72]

Hi Mack, Just thought of this & sorry I'm late with it! It is possible that sone one could have used the GM Prom as a blank and burned a new program on to it. Sorry I had a brain fart! I know the stuff to do this is out there & if the eng temp & the fans are keeping your motor down below the 215* mark without you using the aux fan switch and you don't have a CAGS by-pass on the solenoid harness on the trans...then the PROM is doing all that. Usually if you burn the CAGS to the chip it turns off the "1 to 4" light where as the by-pass doesn't.

Anyway, sorry for being asleep in my last response! Did you check out Haibeck's site? He has some great info on PROMS there. :thumbsup:

Gingle bells!:cheers:
Tom

[ZR-1 Mack]

Thanks Tom. Are you gonna post your location on the ZR-1 Owners map?

Been on the site alot, just forgot he had the info I needed.

At this point anything is possible with whats in there. I'll probably put in a new chip as soon as I can next year. Then I'll know what I have and I can get the Power Key bypassed at the same time.

:thumbsup:

[tomtom72]

Hi Mack,
okay I'm on the list! I'm not too good with software, so it took me awhile to get there. I'm always afraid I'm gonna break something if I "click" the wrong thing!:o

Yea, isn't there alot of neat stuff on Marc's site! I go & read up every now & again just to make sure I've got it straight.

Gingle Bells!
:cheers:
Tom

[Tyler Townsley]

The only way is for someone to pull your calibration from your chip and compare it with a known stock calibration. There is software that does this. Check to see that your cags wireing is still connected as that is the easiest way to defeat cags and is cheap.

Tyler

[WB9MCW]

ZR-1 Mack the front plate is an air ram for the intake...different then the big mouth which is for engine cooling reasons...fyi...the front plate ram air does work and is good for a small hp gain!!! now that i think abt it the big mouth would put more air right up to the air box of the c4 so it too might help a bit but prob. not near as good as the front plate deal!!! i might be off base with this one i would have to go study the whole thing...any others chime in if u have thought abt this at all. it may be the path of the big mouth would do little if anything for higher psi around the air box because the factory had a blocker flap to prevent hydro lock up in case u hit a rain puddle at speed the prevent h20 injestion into the air intake...now if u remove the blocker well then it might help but the hydro lock would be a big concern in wet weather!!! no doubt!!!:blahblah: :handshak: