More issues with MSD
Thread Starter
Racer
Joined: Aug 2005
Posts: 336
Likes: 3
From: State of Confusion
More issues with MSD
Hello All,
I've got a '90 Corvette L-98 with the classic GM electronic HEI and I thought I would give the existing system a little boost with an MSD Blaster internal coil. I've been through two of these coils from Summit Racing Equipment and they haven't performed well at all. The first thing I noticed was that the tach would wigg out between 3500-4000 RPM and then it became apparent that it was wigging out the computer also. The computer was not sending a signal to the distributor to advance. I put the 15 year old, 113K mile factory coil back in and the problem was solved. How do I know this you ask. Well, the best 1/4 mile I could manage with the MSD coil was a 14.9, the factory coil got me a 14.0. This a stock 'vetter running on weather checked GS-C's. Now don't get me wrong fellas, I'm not downing MSD ignition. I have always felt that they are the best in the ignition business, bar none, and I still feel that way. It seems as though the MSD coil is producing so much energy that it's freaking out the factory electronics with radio interference, just a theory. What do you folks think? Has anyone else had this problem? How did you fix it? Did you fix it? Thanks for your inmputs in advance and keep the rubber side down!
I've got a '90 Corvette L-98 with the classic GM electronic HEI and I thought I would give the existing system a little boost with an MSD Blaster internal coil. I've been through two of these coils from Summit Racing Equipment and they haven't performed well at all. The first thing I noticed was that the tach would wigg out between 3500-4000 RPM and then it became apparent that it was wigging out the computer also. The computer was not sending a signal to the distributor to advance. I put the 15 year old, 113K mile factory coil back in and the problem was solved. How do I know this you ask. Well, the best 1/4 mile I could manage with the MSD coil was a 14.9, the factory coil got me a 14.0. This a stock 'vetter running on weather checked GS-C's. Now don't get me wrong fellas, I'm not downing MSD ignition. I have always felt that they are the best in the ignition business, bar none, and I still feel that way. It seems as though the MSD coil is producing so much energy that it's freaking out the factory electronics with radio interference, just a theory. What do you folks think? Has anyone else had this problem? How did you fix it? Did you fix it? Thanks for your inmputs in advance and keep the rubber side down!
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
The MSD box on the 89 really isn't necessary, the HEI is a good piece. When you use the MSD coil (I do) make sure and use the right resistance bushing in the cap, or your tach will do a tap dance. I can't recall for the life of me which one I used, but I have to pull the dist. in the next day or two, if I come across this thread again I'll post which one i used so the tach acts normal 
