MSD83647 Digital HEI Module for GM

This part is junk, lasted 3 months then died. MSD used to be good top of the line but now everything thing I've bought from them since February this year has been junk. Don't know if it's because of staff shortages or what but quality control hasn't been worth a crap lately. Do not waste your money on this part.

This is a great little product to add spark reliability, even at high RPM, without forking over the big bucks for a full Multiple Spark Discharge system. It still keeps the stock appearance of a regular HEI with some good perks. Even with the right idle mixture, there were a few misfires every now and then but this seemed to clear it up very well. The rev-limiter function is very easy to use and can help prevent over revving that could cause engine damage. Overall, I noticed a better low-end throttle response and SLIGHTLY better miles-per-gallon. Install was extremely easy and has not given me any issues at all for the time being. I am one satisfied customer.

I put this on my 89 ford 302 and it works great, no problems running it hard for a few months now. May even rev up a bit better than the old set up and the reve limiter works and is fun to set at different rps.

works well

I ordered one of these September 2015, it lasted less than a year and died. Sent it in for warranty work. In the meantime of course my truck wasn't operational. So I ordered a SECOND one. (Bought August 2016). Installed that one. Two years later that one is dead also. I'm not going to bother installing the first one that was "fixed".I have an electronics degree and 24 years of experience. I can say with 100% certainty that my trucks wiring and electrical system is good. These units are not reliable enough for me to trust.

Works great in my '79 Corvette's HEI distributor, along with the MSD coil 8225

Works exactly how it was suposed to

lasted 10 minutes then poof. nothing. will give it one more try