Hi guys. I need a little help here. I got a 86 IROC-Z and I stabbed in a 350. I got a Hypertech PROM (127062 model) for the 1987 350 TPI. So its right on the money as in my engine conversion. I just started getting a troublecode 51. I went to Autozone and got a Reman Cardone ECM. I thought everything was good until on my way to work this morning, I got the same sputtering as before. I pulled over and jumped pins A & B and behold..... Troublecode 51. This leads me to believe that the Hypertech 127062 PROM chip is bad. So my question is, is it ok to temporarily run my 350 engine with a 305 OEM PROM chip? I can easily put back the 305 Knock sensor. I have 22 lb Bosch III injectors installed. Should I be concerned if I run the 305 PROM along with the 22 lb Bosch Injectors?

 

bump

 

Your engine will run on the 305 chip, but not perfectly, it may surge alittle bit because the injector constant is different.
Personally I'd ditch the hypertech chip and find a stock gm chip to run. You should also consider learning to burn your own prom and do some datalogging, there is alot if information about it here.

 

I prefered the Hypertech PROM because I was able to use a 160* thermostat. This PROM is perfect for the hot summers here in the Imperial Valley ( normal range of 110* between May through August). But I called Hypertech and they told me that a replacement PROM was legal, but they dont sell it to the public, only to merchants. So I called Summit and Jegs and they told me that it is not California legal. So Im stuck. I would like to have a OEM 350 PROM but I dont want to run the chances of buying a PROM from somebody other than a store because it's probably bad(which is most likely the reason why its being sold in the first place). I may just throw in my OEM 305. Do you know anyone that sells after market standard PROM's that are not too heavy on the wallet?

 

Email Thomas@houseofcamaro.com, He's in Simi Valley sells nothing but used fbody parts
he may be able to help you. When I retrofitted electric locks and electric mirrors into my 86 he supplied all the parts

 

I will contact him right now. Thanks bro

 

I was browsing TPIParts.net and I read the section for PROM programming. My question is, Would I run into issues if I leave the AIR SMOG enabled in the PROM even if I have stripped out the SMOG system from my IROC?