Apparently, not all timing lights will work or are compatible with MSD multiple spark ignitions. Does anyone have experience with this situation or suggestion regarding what timing light can be used successfully with the MSD multiple spark ignition (like the MSD Street Fire or 6AL)? Thank you.
I have a couple of cars with complete MSD ignitions: MSD distributor, 6AL box, and MSD coil. I use an older Sears Craftsman inductive pickup timing light with the set back dial, and it works fine.
Have used all kinds of timing lights with MSD systems (6A, 6AL and 6ALN) thru the years and never had one that didn't work. Dial back, inductive in 3 different brands, non-adjustable in 2 brands and have borrowed several at the track. All worked fine. SPark
At about 3300-3500 rpm, my digital timing light starts to pick up the multiple discharges. My old Sears does not. Fortunately, I recurve my distributors so that all the advance is in before 3300, so I still use my digital dial back light.
Some of the newer digital dial back lights don't work too well on multi spark systems.I use a non dial back light with inductance feature and a timing tape.
"Should" being the word. It's a known issue with some dialback timing lights and MSD, maybe some others, if the online automotive forums are any guide. Maybe RFI? Lotsa juice flying around in an ignition system, electronics aren't shielded very well sometimes.
Interesting....it's been years since my scope worked (old SUN) but when it did, and I put something with MSD on it, the multiple sparks were clearly visible, and as you increase RPM, the number of sparks per cylinder drops, and goes down to one at some RPM around 3500. But that's only my memory, I could be mistaken. I don't have a fancy digital light to play with. I do have one of those 20+ year old dial back Craftsman lights as pictured above, and it has been working fine for me. Although I took the MSD out of my 55 a few years ago, right before I sold the car. I did recently install it in a slightly OT car, and I forgot to check the timing after the installation, maybe I ought to do that
I used a craftsman non dial back for years until it broke. I now use a msd brand timing light. its battery powered and produces a light so bright it can be used on a sunny day with no shade.
I bought a new one at Sears a couple of years ago because my Snap-On finally bit the dust after 40 years. It worked for a minute and quit. I took it back and exchanged it and it did the same thing. Got my money back , went to Advance Auto Parts and bought a cheap $30.00 light and it works fine. All M.S.D. stuff on my car.
Brian, when you say the MSD timing light is battery powered, are you saying powered by the car battery or a self contained battery?
I use a battery timing light as well - and yes, it has it's own batteries in it (2 D cells). Besides being accurate, it is pretty convenient, just clip the lead on the plug wire and push the button...
The MSD 8991 timing light has three AAA batteries in it, so you don't need to connect alligator clips to 12v.
I have a Cornwell dial back. It isn't accurate with the StreetFire or 6AL boxes, but worked fine on my 7AL box. For some reason it was off by about 15* on the SF and 6 AL boxes. MSD website has all of the info and what lights work with their units.
If you look at the specs on the Summit Racing web site for each timing light. It specifically shows that many (most) of the timing lights are not compatible with multi spark systems.
Mine is powered by 4 small batteries. It comes in a plastic case. Expensive but very bright. I don't have fenders or a hood to block sun light. I also don't always have someone around to hold up a piece of cardboard to block the sun. It's very bright. Wizards warehouse has them the cheapest.
When I get a chance, I'm going to go back and compare with my old Craftsman to see if the timing is "spot on". I will let you know.