DIS: better keep the trailing leads on the trailing distributor?
 

Got Direct ignition, with MSD and two stock coils for the leading Sparks.
The trailing ignition is original.
I had the trailing leads hooked up on the leading connections on the distributor. As recommended in the DLIDFIS write-up.

I have a cheap digital rev counter in the dash. Sometimes this rev counter goes crazy. Something is interfering with it. I found out it was the distributor. I moved the trailing leads to the trailing connections, and the rev counter was back to normal.

It seems that the distributor rotor is not pointing to the leading points, when the trailings are firing?

I got the timing set as standard, and the vacuum advance hooked up as on the DLIDFIS write up. (on the second port from the front) The distributor and rotor ar recently renewed.

So leave the trailing leads on the trailing connectors of the distributor.

I disagree.

The leading and trailing are centered. Infact the leading portion of the rotor is a lot easier at handling way-off timing as it is wider to cover any timing you wish to use. And because trailing is usually at least 10 degrees retarded, or in your case closer to 20 degrees, you've got plenty of width to use on leading. Take a look.

My guess is your cap is getting old and needs some corrosion scratched off of the aluminum contacts inside. Take a look.

To put it another way, take a look. :)

I will take a look, but it will be tomorrow. :scratch:

Lots of use have moved our trailing wires to the leading part of the cap with zero problems.

^ yup I've done this many times with no issues.

Well, i looked, and you are right and i am wrong.

Attachment 654877

The leading and trailing points making contact at the same time.

I assumed that the trailing points are 20' rotated in the distributor.

Still i thing its strange that i got issues when using the leading points, and not when using the trailing.

My distributor is acouple of years old. Seems like it's crap quality. I will try to buy Original Mazda distributor.

From the photo those look like brass contacts. Supposedly higher quality than aluminum. However all recent manufactured caps use aluminum so maybe aluminum is the better material? Give it a try.

Dude did you check your ignitors? One set could be bad causing this issue.

I have lost my stash of ignitors in the past 6 months. It is like they were all on a timer to go out this year. I am talking about 7 of them on different cars!