MSD Install

[73cudabr]

Hi Guys,

Had an ignition miss, and since I didn't know the last time the car had a tune up, I thought I'd attempt to install some new tech on it with a full MSD System. Distributor, Coil, wires, 6al-2 Programmable, and plugs. I've read the site, and have seen mixed reviews mainly around cost, to output. However I had the money to burn, and thought that long term as I make more modifications having a programmable box would be nice.

I've really never replaced a spark plug before (yes make fun of me, but I'm trying to learn) so it took me a while to install. I double checked firing order when taking off the old cap, and made sure to mark the rotor on a fixed point as to not mess up timing too much. To my surprise the engine fired over after my install. I thought for sure I'd mess something up. However I can tell that it's not running right, naturally I believe some tinkering needs to be done to dial it in. I hooked up a analog timing gun (i believe MSD recommends that for digital box) and noticed that my timing is jumping around at idle. A few searches on the inter web shows me that this seems common if you have the wrong timing light. Since mine seems to spec, i'm missing something else.

I'm going to be trouble shooting this over the next few days. Currently I have the Ground to MSD box hooked up to the frame. Going to try and run it directly to battery to see if that helps. Also on my first attempt to find a 12v ignition source I failed. So I just hooked the ignition wire temporarily to the battery terminal. Not sure if that would mess with the ignition at all, other than having to remove the wire to shut the car off. So I'm going to properly hook that up, and change the ground then recheck.

Plug wires came with the long straight boots instead of 90 degree boots. I had trouble getting the boot to seat all the way up the plug. I ordered some 90 degree boots just in case I have some bad connections I can install those in the tight spaces. PLug number 3 for example was a pain, and the main source for what took me so long.

I wanted to get this out there in the event that somebody has run into this before, and can guide me to a simple fix. For what it's worth as I rev the engine the timing advances and smooths out to where it does not jump. Prior to the install the timing was smooth last time it was checked.

I welcome any suggestions. Thank you.

Bill

[70chall440]

A couple of thoughts/things to look at;

1. bad ground somewhere; remember that the ground has to be clean, no paint or rust under it. The frame or a bolt on the engine/body is fine so long as it is clean. Also make sure you have a sufficient gauge of wire, doesn't have to be 8 or 10, but shouldn't be smaller than 14.
2. your cap is arching across terminals
3. your distributor isn't advancing correctly (stuck or sticking weights, bad springs, etc)
4. ensure your timing light is on the #1 plug wire (may seem simple but I have screwed this up myself)
5. plugs not properly gapped (normally should be .035, but with MSD I believe it is something like .045)
6. loose connections
7. wires arching to a ground (remember, electricity takes the path of least resistance)
8. not sure what you mean by "wrong timing light"; so long as it is set to 8 cyl I would think it should work unless the MSD has an effect on this (which I don't know about as I have yet to use one)
9. As to your switched 12V source, there are lots of them in your car, you need a test light and do one of the following;
  A. turn the ignition switch on, test wires until you find on that is hot, then turn the switch off and test again. If it is not cold you are good, if not start over.
  B. have a helper turn the switch on (without starting the car), test until you find a hot wire, then have them turn it off and test again. Same rules as A.

Not rocket science or magic, just have to be methodical and systematic. Stay on one task until exhausted before moving on to the next. Don't cut anything unless you know what it is and why you are cutting it.

[73cudabr]

A couple of thoughts/things to look at;

1. bad ground somewhere; remember that the ground has to be clean, no paint or rust under it. The frame or a bolt on the engine/body is fine so long as it is clean. Also make sure you have a sufficient gauge of wire, doesn't have to be 8 or 10, but shouldn't be smaller than 14.
2. your cap is arching across terminals
3. your distributor isn't advancing correctly (stuck or sticking weights, bad springs, etc)
4. ensure your timing light is on the #1 plug wire (may seem simple but I have screwed this up myself)
5. plugs not properly gapped (normally should be .035, but with MSD I believe it is something like .045)
6. loose connections
7. wires arching to a ground (remember, electricity takes the path of least resistance)
8. not sure what you mean by "wrong timing light"; so long as it is set to 8 cyl I would think it should work unless the MSD has an effect on this (which I don't know about as I have yet to use one)
9. As to your switched 12V source, there are lots of them in your car, you need a test light and do one of the following;
  A. turn the ignition switch on, test wires until you find on that is hot, then turn the switch off and test again. If it is not cold you are good, if not start over.
  B. have a helper turn the switch on (without starting the car), test until you find a hot wire, then have them turn it off and test again. Same rules as A.

Not rocket science or magic, just have to be methodical and systematic. Stay on one task until exhausted before moving on to the next. Don't cut anything unless you know what it is and why you are cutting it.

Thanks for the response. I decided to start over with my plugs and wires. Upon pulling each plug, number 3 was the culprit and causing a miss fire. Re checked the gap on the rest of them, turned it over and ran perfect. Looking forward to bringing it to the dyno so they can dial in the programmable box.

[dodj]

Also check reluctor gap. 008"
Can cause inconsistent spark if out of spec.

[73440]

To change plugs involves sometimes lying under the car, reaching over the fender, reaching thru the access panels, multiple socket arrangements.
Was having a misfire recently, pulled # 8 and absolutely no gap. The person before must have dropped the plug and not rechecked the gap.

[73cudabr]

The plugs were a major pain. #3 plug took me over an hour to put in, I dropped it multiple times. Likely caused the gap to get messed up. A friend of mine who does this for a living came over and put #3 plug back, in about 30 seconds. I had a spark plug wire with a straight boot. He cut the boot off and slide the spark plug into it. Then used the extra 3 inches of rigid/flexible length that he got to thread the plug in between the headers and steering box. I was happy and pissed at the same time, because had I have thought to do it, I would have saved myself a lot of swearing and frustration the first time.

[Chryco Psycho]

small diameter vacuum hose can be a lifesaver installing plugs  this allows turning the plug without dropping it 

[70chall440]

small diameter vacuum hose can be a lifesaver installing plugs  this allows turning the plug without dropping it 

 

[Jefferyfem]

Ive got a msd 6al to install in my F-Body as I really want a rev limiter. Would like to install it so I can easily switch back over to the orange box should the msd fail while out on the road. Anyone done this? Any advise??

[HP_Cuda]

Why not just add a rev-n-ator or a rev-limiter then?

The wiring of a MSD would be a bit painful to switch back and forth but can be done.

[dave73chally]

Somewhat off topic, but where did you buy all your MSD stuff?

[HP_Cuda]

Summit, had it in less than a day.

[Chryco Psycho]

Why not just add a rev-n-ator or a rev-limiter then?

The wiring of a MSD would be a bit painful to switch back and forth but can be done.

  better Ecu that plugs into the stock system & easily replaced if needed