I am swapping a 305 to a 400 and wanted to keep the carb and dist.,does any one know a company that sell a prom for the change.

 

If you have a computer controlled carb, the PROM controls only part throttle A:F mixture, with the M/C solenoid, and spark advance, so if you have the carb rejetted for the larger cubes, it should be OK. An aftermarket chip, from Hypertech, for example, would have the effect of redoing the spark curve to be more performance oriented - earlier & additional advance.

Tim

 

Thanks Tim