MSD and Points

[leadrsa729]

Hello -

I've got an MSD 6A CD box, a MSD Blaster High Vibration Ignition Coil, the MSD Tach Adapter, and new Magnecor spark plug wires.

I've wired in the MSD Box as according to the instructions with Heavy red going to the Starter, and the Heavy black going to the ground bolt on the driver side of the chassis in the engine bay.

The ignition coil has no ground on it, only the black and orange wires going to the MSD box. The Tach Adapter is spliced in to the points wire and the white MSD box wire along with the ignition key wire and the red MSD box wire.

I'm having major problems with my points with this setup. I keep scorching the points to the point that the engine runs horribly in the lower RPM range. Its so bad I have a hard time getting going in first gear from a stand still.

MSD says that a points setup requires a 0.8 ohm ballast resistor be installed on the positive wire of the coil. I don't have this and I didn't see this anywhere in my original wiring instructions that came with the MSD box. Nor have I yet to see it used in any pictures here.

Has anyone here used this resistor, or know anything about it? Should I ground the coil directly and add in this resistor? I can't think of anything else that would be wrong other than a poor grounding issue.

Thanks in advance,
Sanford

[Bob Kontak]

Ground the coil directly to what? Don't do that. Just put the ballast resistor in the positive line as MSD says.

Here is a ballast that would work.

I bet, although I did not check, local parts stores would have them

MSD Ignition - 8214 - Ballast Resistor - Goodies Speed Shop

Autozone http://www.autozone.com/autozone/accessories/MSD-8-Ohm-ballast-resistor/_/N-25rh?counter=0&filterByKeyWord=ballast+resistor&fromString=search&itemIdentifier=139539_0_0_

[leadrsa729]

Thanks Bob -

That is definitely the resistor in question. With my old Perma-Tune setup the coil had a wire from the negative terminal to one of the two bolts on top of the fan housing that held the coil in place, along with the wire that led back to the box. That's what I was referring to when I asked if I should ground it directly. I apologize for any confusion.

Sanford

[Howard M]

Sanford, consider a Pertronix points eliminator. Many of us have installed one with the MSD. Mine has been problem-free. No more points, no more wear, no more timing drift.

[Bob Kontak]

No confusion. Just ignorance on my part as I had never seen a direct physical tap to ground from the negative side.

I would get the pertronix immediately AFTER you dial the existing system in. Too many changes at once can cause headaches.

[Rich Lambert]

I had the same issue with an MSD box burning up points at an alarming rate. Just be done with it and replace the points with a Pertronix unit.

In my case, even though multiple people whose opinions I respect told me to get the Pertronix, I resisted because I thought points were so simple and easy to maintain...I was wrong. The only regret you'll have is that you waited.

[BSNMOE]

I have noticed that in the past few years my points rubbing block has been wearing down at a much faster rate. Also, last year my points seemed to be burned. Lucky that my wife had an emerory board in her purse.

I have MSD and with MFI so on hot starts I have to hold the key on for 10/20 seconds. I thought that was what burned my points, but have not had a problen since. I wonder if holding the key on with Pertronix will burn out that system. Then, if on the road, you really have a problem.

I really never liked that transmission braided ground strap, so I replaced it with a regular ground cable. I also added a ground cable off my timing chain cover to a bolt on engine mount.

[T77911S]

i did not use a ballast resistor on mine. i also did not need the tach adapter. you did not state the year of your car but i would assume it is older than 78 since you have points.
the coil was grounded on the "old" system. MSD just runs the ground directly back to the MSD unit.

i also kept my points. anything electronic is just one more thing that can keep the car from running.
the points should not burn. there really is not enough current in this setup to burn the points. i have out around 40k miles on my car and have never changed the points and not really done anything with them. since the points are really just a switch, i just eyeball the gap setting and go. i check my timing at valve adjustment time and that is it.
this is what i love about this car. the simplicity and reliability. the only things that will stop me dead are a bad fuel pump, MSD or coil. i keep and old permatune and coil in the car just in case so really just a FP will stop me.

[Christien]

Originally Posted by T77911S

you did not state the year of your car

It's a 72S - it's listed under his avatar.

In my 72T, the MSD installation (6A and with MSD high vibration coil) was a piece of cake. White wire to the points, no ballast resistor, no tach adaptor, and it worked fine for 3 years until I swapped the engine with a 3.0 last month, and went to an SC dizzy (no points).

Try removing the tach adaptor and ballast resistor, and wire it exactly as stated in the manual. It worked perfectly fine for me, and I'm not very good with wiring

[leadrsa729]

Thanks for all the replies!

I'll try removing the tach adapter and see if that helps things.

Also, I'd like to add the additional ground strap from timing chain cover to engine mount bolt. Can anyone tell me what a good size guage thickness I should use for a ground strap?

Sanford

[Christien]

Chain cover to engine block? Are you sure you're thinking of the right thing? I could be wrong, (wouldn't be the first time!) but I've never heard of such a thing. Besides, it's all connected metal, so all grounded already.

[leadrsa729]

I'm not sure either really! I'm only thinking that it can't hurt to create additional grounds, or does it?

[T77911S]

thats a strange place for the year to be, never seen it there.

the 3.0 with the electronic dist needs the tach adapter, the points do not, based on mine.
i did not ground my coil. i dont think you need the ballast resistor either.

there should be a ground strap from the tranny to body. just clean that and make sure it is good a tight. if you did not have a good ground, you would have starter issues.

the points should not burn, there is not enough current to do that. the car could be trying to use that path for ground for the electrical system so do the above.


check your timing and make sure the advance is working properly.
i would not run any other grounds. make sure the battery ground is clean too, both ends.

[BSNMOE]

Originally Posted by Christien

Chain cover to engine block? Are you sure you're thinking of the right thing? I could be wrong, (wouldn't be the first time!) but I've never heard of such a thing. Besides, it's all connected metal, so all grounded already.

From the timing chain cover to the bolt which bolts the motor mount to the frame.

[Aetto]

Also check your spark plug gap if you haven't already , should be 40 to 50 ths and 1 to heat ranges colder per MSD tech support. This is critical as the higher Resistance with the smaller gap will blow rotors and points. I run NGK BPRY5EY 1233 plugs gapped at 50ths in my 78 3.0 SC. Spiral wound plug wires are a must as well I run Magnacore supplied from our host. Also you might try reversing the wires on the distributor pickup. I had major issues with mine took me a month to work it all out. See the last page of my thread ,misfire I gave a detailed list of the whole procedure that I used to correct mine.
Once they are installed correctly they are outstanding my car runs great.