msd ignition
Thread Starter
Burning Brakes
Joined: Nov 2004
Posts: 1,028
Likes: 0
From: San Antonio Texas
msd ignition
thinking about installing an msd ignition on my 79. wonder what forum members think about them. i've read a lot of stuff on the internet about them. people seem to either swear by them or swear at them. like to hear your thoughts. car is generally a street driven weekend cruiser.
Race Director
Joined: Mar 2001
Posts: 11,322
Likes: 1
From: Living in the Hartland
On a stock eng I do not think you will see any diff as long as all your ignition parts are up to snuff. The MSD type boxes help to smooth out the idle and help low end performance on eng's with long duration cams. You can get better formance out of your HEI system by changing your timing curve and possible your ing module.
Instructor
Joined: Sep 2004
Posts: 168
Likes: 0
From: Houston Texas
I run a MSD 6AL on my 79 with a 406. Better idle and low end. Also more reliable than an HEI. I had the HEI modules fail twice. I also have a used 6A I bought for $30 that I carry as a backup just in case but it's been reliable for 4 years and 35K miles. Mounted it on the passenger side firewall but on the wiper plenum side. Keeps it away from engine compartment heat. I also have the aftermarket wiper plenum cover that hides it and protects it from rain. Its a tight fit. Since it's hidden from view I put a switch on the ground wire that is one of my theft prevention devices.
Instructor
Joined: Sep 2004
Posts: 168
Likes: 0
From: Houston Texas
I have a MSD 6AL on my 79 with a 406. Better idle and low end. Also more reliable than a HEI. I have had two HEI modules fail. I also have a used 6A that I bought for $30 as a backup. So far have not needed the 6A after 35K miles. I mounted the 6AL on the passenger’s side firewall but on the wiper plenum side. Bought one of those wiper plenum covers that hides it and protects it from rain. Because it is hidden I installed a switch on the ground wire for theft protection. It’s a tight fit but will.
Melting Slicks
Joined: May 2004
Posts: 2,744
Likes: 848
From: Gulf of America
2023 C7 of the Year Finalist - Unmodified
2018 C3 of Year Finalist
Got the entire MSD ignition (6AL box-tachdrive distributor-coil and wires) on my modified smallblock. Been rock steady for some 5 years now. Love the rev control feature.
Thread Starter
Burning Brakes
Joined: Nov 2004
Posts: 1,028
Likes: 0
From: San Antonio Texas
thanks for the input. as i suspected, opinions vary about these ignitions. engine rebuilt before i bought it so not sure what's inside but it is the original L82 block, aluminum heads, aluminum manifold, headers and stock quadrajet. hard to start when cold, idles very poorly when cold, better when warm and runs fine when warmed up to operating temperature. the pluses i hear about these ignitions is easier starting, smoother idling and better low end response. all problems i'm trying to address. i've heard the boxes are noisy if mounted in the cabin. main negatives i've heard are they tend to burn out coils as they send 500+ volts to the coil as opposed to the 12 volts of a stock ignition and they trigger the spark many more times than a stock ignition.
Racer
Joined: Nov 2002
Posts: 320
Likes: 0
From: Bradenton Florida
i use mallory igniton because it came with the car. i dont know how the mallory ignition works because when i bought the car it was only firing on 7 cylinders. the bottom off the valve broke asnd got embaded in the piston. ill have to take some pictures off it.
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Melting Slicks
Joined: Jun 2001
Posts: 2,429
Likes: 14
From: CA
Originally Posted by greyghost79
thanks for the input. as i suspected, opinions vary about these ignitions. engine rebuilt before i bought it so not sure what's inside but it is the original L82 block, aluminum heads, aluminum manifold, headers and stock quadrajet. hard to start when cold, idles very poorly when cold, better when warm and runs fine when warmed up to operating temperature. the pluses i hear about these ignitions is easier starting, smoother idling and better low end response. all problems i'm trying to address. i've heard the boxes are noisy if mounted in the cabin. main negatives i've heard are they tend to burn out coils as they send 500+ volts to the coil as opposed to the 12 volts of a stock ignition and they trigger the spark many more times than a stock ignition.
Thread Starter
Burning Brakes
Joined: Nov 2004
Posts: 1,028
Likes: 0
From: San Antonio Texas
really? stock gap on 79 is .045. MSD recommends INCREASING gap by at least .005 to .050 or even .055. your recommendation of .040 sounds too conservative. it wouldn't take advantage of the increased voltage that way, would it???
using Moroso Blue Max spiral core wires. MSD says they're o.k.
using Moroso Blue Max spiral core wires. MSD says they're o.k.
Melting Slicks
Joined: Jun 2001
Posts: 2,429
Likes: 14
From: CA
The strength of the spark is greater/fatter with the MSD, regardless of the gap. The plugs will last longer too. Extra big plug gaps - .050-.055, are for lean, low performance smog motors. ). 040" should be fine on any high performance engine.
Instructor
Joined: Sep 2004
Posts: 168
Likes: 0
From: Houston Texas
You shouldn't have any trouble if you buy the right coil with the proper impedance. The MSD will provide you with a list of coils that work and they are not all MSD.
Yeah you can go beyond .040 plug gap even to .055. But you will need good plug wires. The increased gap increases the voltage rise before the spark. Electricity follows the path of least resistance. If your plug wires have poor insulation the increased voltage rise may cause them to fail and short the spark and the plug will fire poorly or not at all.
The rev limiter is nice to have especially if your drag racing with a standard shift. If you miss a gear it won't let the motor spin up to possible damage or destruction.
Yeah you can go beyond .040 plug gap even to .055. But you will need good plug wires. The increased gap increases the voltage rise before the spark. Electricity follows the path of least resistance. If your plug wires have poor insulation the increased voltage rise may cause them to fail and short the spark and the plug will fire poorly or not at all.
The rev limiter is nice to have especially if your drag racing with a standard shift. If you miss a gear it won't let the motor spin up to possible damage or destruction.
Racer
Joined: Oct 2004
Posts: 318
Likes: 0
I am also running a complete MSD system and have had no problems.other than trying to find a place to mount the Blaster coil vertically. MSD recomends this due to the fact that the windings are covered in a liquid to keep them cool because of the increase in voltage. So they say
