Great site. I've been lurking, searching, reading, googling, etc. and now I know just enough to be dangerous and/or cost myself lots of money I just had my 305 replaced with a 350 in my 1988 G-20 Van. The drivetrain is now a 350, TH400 and 3.73 gears (I had them changed from 3.08's a few years ago) I now know I need to replace the injectors and ECM or PROM as well as the knock sensor. I have a 1227747 ADXB (305) ECM and understand I can replace the PROM. My question is which PROM? On ebay I can get 122774 AMUR PROM which I can only find that it is for 1988 5.7L trucks. I can also get 122774 ANLW which apparently is for 89 5.7L trucks with auto trans and 3.73's. Which auto, the POS OD? I think my TH400 downshift is controlled by the ECM, is that correct? Anyway, my head is spinning and I just need to know if AMUR or ANLW PROM would be best with my 350, TH400 and 3.73 gears. Thanks a bunch and feel free to move this thread if it belongs in the engine swap forum.

i WOULD SEND A PERSONAL EMAIL TO MEMBER FAST355. HE HAS THE "VAN" EXPERIENCE ON THESE BOARDS.

Thanks for the heads up. I went ahead and purchased the AMUR chips and they got here today. For 26 bucks I figured it was worth a shot. Gotta start somewhere. In fact, my van is at my mechanics now. He was doing a 500 mile check over and oil change for me and while he was at it he installed a new 350 knock sensor, ESC and 350 injectors. I stopped in and popped the chips in the ECM. I was going to do it all myself but he offered to do it no charge! I should get it back tomorrow. It was running rough around town but was pretty smooth on the highway. I suspect it will be much better now.