Hi, I have a 91 camaro rs. I converted to a 350 crate motor. It's tbi with an msd 6a box and dui distributor. For some strange reason my car keeps killing distributors. I have injector pulse but no spark? Anyone have any ideas?

 

Get rid of the MSD box and put the DUI back like it came.

Then come back and tell us what happened.

 

Sofakingdom, thanks for the response. After hours/days of reading posts and finding nothing but negative opinions about the msd box when used with my particular setup I understand now that most guys believe its not worth the headaches. My question is why? It's a simple set up that's works with every other application. Why not mine? Does anyone actually know the "science" behind why it's so problematic with tbi?

 

Not sure what you're asking...

Has nothing to do with "science", "TBI", or any of the rest of that. The MSD is just ... not a real good choice for street use. Well marketed but under-engineered. Too unreliable. In too many ways. In case you haven't noticed.

The DUI is one of the best products on the market. Put it back like it came.

Yes I knew Kelly Davis (the D in DUI), RIP, from back in the 70s, when we would twist up ... distributors ... in his garage. His son seems to be a good kid as well although I haven't met him. Too many years in between. But the product apparently remains the same as Kelly envisioned it.

How does it work now that you've got rid of the MSD and put the DUI back to its stock condition?

 

I appreciate the help and advice your giving me with my post. However, I respectfully disagree with your comments. - "not a real good choice for street use. Too unreliable. In too many ways. In case you haven't noticed".To be fair there's lots of pros and cons that you can find on the internet about msd. Saying msd is too unreliable is fact less and just your opinion. If they make such a bad product why are they so successful? I don't want to sound like i'm team msd i'm just looking for facts. You mentioned about your friend being Kelly Davis who happens to be the founder of dui distributors and your confidence in his product. I also have a friend who happens to be Michael Steven Davis or MSD for short! Obviously he's the founder of msd ignitions.....Just a little humor there. In all seriousness i do have a friend who's been using the same msd box for the last 10-12 years with no problems. Again, i just want to know why it doesn't work and why it seems like i wasted my money on a little red box? Thanks again for your input. Hopefully with the box off it will go back to running as good as it was.

 

MSD stands for Multiple Spark Discharge. The name of the company is Autotronics.

You're not the only one that's had trouble with MSD stuff. Your problem is in fact fairly typical of the complaints.

They are successful because of good marketing. Unfortunately there's LOTS of things in the hot-rod business like that... people WANT TO BUY THEM regardless of the actual results. They are designed TO BE SOLD, not TO WORK. And in all fairness, when a MSD setup works, it works pretty good; but when it doesn't, ... it ... just ... doesn't. Which of course is the situation where you are now. Some individual boxes have better luck than others, which is why your friend's might have survived all this time. Doesn't mean that yours should or will.

If I had a dime for every part that had been sold to a consumer for use on a street car because "all the fast cars at the track have it", I'd be a very wealthy person. But in reality the street is a MUCH harsher environment than the strip in some ways: as an example, to make a 12-second pass down the track at 7000 RPM, you will need about 5600 sparks (7000 revs per minute, divided by 60 seconds per minute, times 12 seconds, times 4 sparks per rev); but you'll need MANY times that number just to go to the grocery store. If a part of any kind has a limited lifetime in simply the number of operations, it'll die FAR quicker on the street than at the strip.

The bottom line is, it's likely that it doesn't work because it's broke; and it seems like you wasted your money, because if it's broke and keeps on breaking, you did in fact waste your money. Harsh I know but candy-coating it won't bring it back to life.

Remove the MSD and see if it works. That's ALWAYS Step 1 of troubleshooting those things. If the car works without the box, there's only one possible conclusion you can come to. At that point it's up to you to decide what to do about it.

 

Hey Sofakingdom,

I totally understand what you're trying to say and it makes perfect sense. Once again, thanks for taking the time out of your day to help out a fellow 3rd gen guy with his issue.

Take Care!