I think that my Mallory Unilite has died on me... won't fire all cylinders anymore. What is a good reliable ignition system to get?

DJ, I had a few problems with a Mallory ignition a few years back. I had the Comp 9000 optical p/u type with the 29440 coil. Supershops (remember them?) featured and talked me into that brand.

I was at a different speed shop that featured Accel distributors. I got one of the "billet tech" ones with a magnetic p/u. Haven't had a problem in 6+ years. graemlins/thumbsup.gif

My mallory stuff was JUNK. Ive gone through a few LED'd and randomly had a box take a crap on me....go to MSD.

3 nights before taking my car to the body shop, I started it up... for the first time in a little more then 2 years. It ran perfectly... did have to give it a shot of starting fluid. The next night I started it again, because I just needed another hit of that wonderful noise. Well a minute or 2 into running, it started backfiring like crazy. I shut it off. The next night I went back out to try figuring out what was wrong. Using a temperature meter, I was able to determine that only four header tubes got up to 300 degrees, the other four where 98 - 100 degrees. There was no spark coming out of the cap for the cold cylinders. So, instead of driving my car up to the body shop, I had to resort to pulling it on the trailer.

For now, I just ordered a whole other Unilite... that way I can take the top parts out and put them in my existing unit. I just want to get it running the quickest easiest way while it is up there.

Then when I get it back home, I'll change the whole distributor.

Is that it on recommendations? MSD or Accel?

Big waste of money, send the new unilite back to where it came from, if you think its the distributer save yourself some money, call mallory and they have a test you can perform with a drivers licence a volt meter and the LED. If it is the LED and you want to buy another one they are cheaper than buying a whole distributer.

MSD...are there any questions......anyone......anyone......Bueller.... Beuller

Fry......Fry........

Time is money. I don't have time right now to be running back & forth doing diagnostics on it. Figured that way I get the cap, rotor & electronics for just about what I'd pay individually.

I did find this info the other day, but haven't had time to mess with it.

http://www.centuryperformance.com/mallory/unitest.asp

Well, I'm an Electrical Engineer and actually tried to market some HI Perf ignitions here in the NE about 10 yrs ago.(not enuff capitalization to compete w/ Mallory and Accel and Holley, and Jacobs and MSD......) I run MSD in my latest ride but there's really nothing wrong with the Unilite except that it hates "over-voltage". Mallory knows this is a problem and sells a protection circuit now. (they really ought to build it into the module! graemlins/clonk.gif ) I've only ever blown one module in 20 years and that was b/c the ground strap broke off the core support on a car with an old mechanical regulator. I've run 11 second cars at 8500 RPM with Unilites and they work fine!!

MSD really isn't infallable either. They haven't really changed their basic design in about 25 years! The Nextel Cup cars run two MSD boxes and two coils on a switch so that they can quickly change over "when", not if, the MSD box fails

If your wiring isn't good, your gonna burn the box no matter who makes it.

Paul D.

I too myself, am an Electronic Engineer and I have torn Mallory, MSD, Jacobs and Excell products down, to the component level. I have tweaked them to the point of using some better components than what came in them, but.....none of them are perfect and they do fail. But, some products and manufacturers are much better than the others.

The things I like about MSD's distributors are so little moving parts. You can not really hurt, screw-up or break a magnet very eaisly. The ignition boxes are second to none and their coils have to matched up to the box in more ways than one to get them to live in Professional performance applications.

The Mallory Unilite is a good unit, but voltage sensitive, as Paul stated. I have run many of them hard....right up to their time in failure. The magnet in the MSD however, has yet to fail. The Unlite is a good product, but I never went back after I changed.

FYI, the boxes used in NASCAR are not your off the shelf 6T's, 6AL's or HVC6's either........dont even think that you are getting the same thing you buy off the shelf. The newer consumer available HVC6 system, is about as close as you could get. But they are on the ragged edge of failure due to the boxes max energy output, max current output and its spark duration in microseconds. Not to mention the systems coil. Specifically the turns ratio and the secondary resistance. There is a fine line between optimum performance and optimum durability....and they are always right on the edge.

I see it this way. There is a reason ALL of the Professional racers out there use MSD products.........NASCAR, SCCA, NHRA, SCTA and SCORE just to name a few........

Thats a pretty strong point made, considering that I dont see anything else but MSD being used. Period.

I believe in the KISS principle. I personally enjoy the Otto Kettering system.

I can store an extra set in the glovebox along with a 3/16X4 inch flat blade and an Allen wrench.

I've seen both Unilite & my own MSD-6A fail.

i had a unilite for over 20 years .
never had a problem and it was connected to an MSD 6AL.
I think you might have shorted it and it fried.

Well Everett, the "price of progress may be pain", and sometimes "better is the enemy of good" but us "sparkies" have a pretty good handle on these here new fangled transistor thangs now-a-days!! :D Seriously though, you can drive a modern electronic igniton, EFI car for over a half-million miles in some cases w/o a single electronic failure. Hell, ya don't even have to change the plugs for 50-100K miles!! Kettering's stuff was good in it's day but pales in the modern, no maintenance, "my car has to run like an appliance" world!

Chicane, I agree about the Uniltes mech. advance system. I've seen a lot of those mechanically fly apart when run at sustained high RPM. Never experienced the same with MSD. Their stuff is always "ready to race"! But the MSD's pick-up coils do "open" electrically from time to time, vs. the mallory that uses an IR photo-diode/transistor pair and shutter wheel for triggering. I don't think either has less moving parts? I still prefer the moving magnet and pickup coil (like most rational people!!) A speck of dust never gets on the pick-up coil and stops it from working, and you can tune the trigger wheels to vary the timing for individual cylinders!! ;)


My personal stuff was actually a lot like the product Crane is marketing now. All electronic advance with programmable curve! Nothing in the distributor but a magnet and pickup coil. That's KISS!!

Paul D.

Paul, I have no arguement with you on EFI, I think its the greatest item since sliced bread, providing it continues to work according to its intended task. :D

But, when was the last time you bought a $3 part for the EFI system to get the car/truck running? ;)

I personally like the new fangled stuff and it cuts down on alot of maintenance. If I were to chose an aftermarket ignition system, I'd go with a magnetic pick-up and a programmable box. But, I'd leave the orig stuff in the glovebox just in case it failed, I could get home. graemlins/thumbsup.gif

Originally posted by dawg:
i had a unilite for over 20 years .
never had a problem and it was connected to an MSD 6AL.
I think you might have shorted it and it fried. After reading the link that I posted above, I am sure that there was a voltage spike that killed it... I didn't have the REQUIRED ballast resistor installed... I was disconnecting & reconnecting the battery with the ignition key accidently left on.

I would think that an optical system would be much more accurate & responsive then any magnetic system.

ROTFLMAO!! Good point Everett, I can barely buy a gallon of gas to put in my EFI car for $3 these days!!

David, with the signal conditioning and digital signal processing electronics that are available now the mechanical tolerances in either system (optical or magnetic)are the limiting factor. Also, photons and electrons both move at the same speed:

186,000 miles per second it's not just a good idea it's the law!! :D

Paul D.

David,
If you didn't have the required ballast resistor installed, I can almost guarantee that is what killed your distributor. I have heard way too many horror stories about Unilites going up in smoke because the resistor wasn't installed. The MSD may very well be a better unit, but I have had no trouble in the last four years out of my Unilite and I have put at least 15-20k miles on it.

I'll stick with the Mallory for the Camaro. I'll just make sure I install the resistor.

djunod,
The Mallory system requires a specific coil in addition to a ballast resistor.
I may still have the proper Mallory unilite coil if anyone needs one, it only has 4.5 hrs on it.
David

The other day I had order a new Unilite, ballast resistor and coil (all Mallory stuff). I haven't installed it yet, because the car is sitting up at the body shop (and it's best that it doesn't run for them).