View Full Version : MSD Ignition?

02-16-07, 07:09 AM
A friend of mine insists the MSD ignition is an upgrade on most any car. He has one that he isn't using right now, and says I can borrow it.

Has anyone ever used one? Can it be used on the LT1? Or my 99 K2500 454?

It multiple sparks below 3000 rpm. I spend a LOT of time below 3000 rpm. On an average day I never see over 3500 rpm. On a punchy day, well, 5600 is nothing and 110+ mph is too....

But I am always on the interest on gas mileage, if this works, I am game for sure.

My thoughts a MSD would be useless on a engine that is already performing properly.

02-16-07, 08:39 AM
Exactly. If the rest of the engine is stock, why should the ignition be upgraded? The engineering department spend alot of time and energy designing a system that works well for a long time. With that said, multiple sparks below 3000 rpm might be beneficial. The stock system does a good job, but I wonder if you might see anything different with multiple sparks.

02-16-07, 09:16 AM
I guess it would benefit some for igniting the A/F that didn't get ignited in the first place.

Now if it increase dwell and makes the spark LONGER, yes, I can see that helping some. Again, assuming the factory spark isn't enough.

They claim that the factory coil is only 37KV and the 96 coil is 50KV or so. So GM updated it for something.

I will probably get the 96 coil, if GM felt there was a need, that can't hurt. Assuming the ignition module is cool with it (pun intended). Maybe the MSD boosts primary ignition voltage.

So the coil is a ratio, and say we put in 12v to it, and it gets 37KV out, that is a 3803:1 turn ratio. With say 15v primary input, that is 57KV output. So a little goes a long way. But the other way is to boost the turn ratio, so 12v gets you 50KV. Then stock primary voltage works.

Which is exactly why in racing they like to use the 16v batteries instead of 12v.

Old Fleetwood
02-16-07, 05:37 PM
A while back on this BB, there was a real dogfight about MSD vs. the stock system. From what I could gather, the GM system seemed to come out on top. Yet, since MSD is out there, obviously there IS a market for it, so it's a case of :stirpot: as far as I'm concerned.
So far I'm happy as a clam with my GM OptiSpark system that came with the car since I've been running Techron additive thru the fuel system every 3rd tankful when I originally thought I had ignition troubles (symptom: Occasional slight stumble in direct drive at speeds above 70).

02-17-07, 11:04 AM
Well, I do detailed fuel economy testing, and a friend of mine has a MSD 6A he said I can borrow as he isn't using it for a while. So with my detailed mpg records, running a MSD vs stock Opti will show clearly if there is any improvements.

I just went through my Opti around the first of the year, cleaned up the cap/rotor contacts removing all pitting and carbon buildup (there wasn't too much, but more than I like to see), replaced ALL the seals except the cap seal (can you?). It was on tight and dry as a bone inside, no evidence of water leak.

SO, if the MSD can help power/economy. I will likely be able to determine it....

02-18-07, 03:22 AM
Thing with the ignition spark is you're increasing the input energy; this increases the rate atwhich the fuel burns and helps it to burn more thoroughly. Part of how an engine is designed is to reduce the burn speed to reduce engine wear and tear and inprove mileage; that's why EGR's were introduced. To get any meaningful boost in performance out of an ignition upgrade you have to take into consideration your spark advance (which should be reduced with the upgrade), air/fuel ratio (which should be reduced slightly), and spark plug type. The main thing I look for in a spark upgrade is to have 99% of the fuel burnt off before it even reaches the cat.

I have an 88 with a 307 in it and I have stock cables with rapidfires installed with a 12v gel battery. She has some damn good get up and go for a big car and before the rapidfires she was sluggish.