My car originally had a 305 tpi, but the previous owner swapped in a 350. When I'm cruising at about 30 mph, it feels like the converter locks because the car starts chugging really low and feels jerky. Is the speed for lockup different on the 305 chip than on the 350 chip? I am wondering if it is possible that the previous owner just left the original 305 chip in there? Thanks for any help.

 

Lockup/unlock MPH settings changed from year to year for even the same engines. They may be different depending on what gear you are in as well.

 

Well it's been awhile, and I'm still having the same problem - this definitely doesn't feel like it should be locking up at this low of a speed, the car lugs along really rough when it locks. I guess my question was if its even possible for a 350 car to run on a 305 chip? Should I find a serial number or something on the computer that could tell me?

 

Also, I've noticed that the car seems to be running rich - from some of the reading I've done here, it seems like that would happen if it was a 305 chip because its for #19 injectors, and I've got #22s. Anyone?

Thanks!

 

You can cheak easily by lowering the ECM,. removing the access cover for the MEMCAL, and reading the broadcast code on the foil label on the PROM. Usually, you can see most of the label through the holes in the MEMCAL cover: