67 Charger MSD/Tach

[bcOH67]

Thanks for any help that can be offered!

I saw in a thread already that I’m not able to connect an MSD with my factory tach. But then another person recommended a new tach board from real time engineering.

Just to clarify- would this new tach board enable my factory tach to work with my MSD? Or is there another step?

Thanks,
Brian

 

[RJRENTON]

Brian,
I believe that the MSD system requires the use of a "tach adaptor" device. Since I'm not a fan of MSD, l cannot tell you what you may need and how to connect it to your tach. Perhaps, the later versions of MSD's offerings do not require an adaptor device. I would inquire directly with MSD to their technical service group as to your specific application.
When I removed an old MSD 6C system, triggered by a Mopar electronic distributor, from the Plymouth, it had a tach adaptor device connected to the control box. BTW....not to beat a dead horse.....I use an original Prestolite dual point distributor in my RS23V0A****** GTX.....it works just fine for me.
Bob Renton

 

[Billccm]

contact rt-eng.com
Great people and the module works great with MSD.

 

[Billccm]

http://www.average-guys-car-restora...-for-68-road-runner-project-beepbeep-part-iv/

 

[TN Mopar]

contact rt-eng.com
Great people and the module works great with MSD.

Bill
To confirm
The RTE tach sender will take the signal from the MSD box and send it to a factory tach? (66 Charger) correct?

 

[Billccm]

No.
You replace the factory tach circuit board with the rt-eng.com circuit board.
Send them an email they will support you on the upgrade.
Watch all my videos on the tach. It shows how to bench test and upgrade to the rt-eng.com circuit board l.

 

[TN Mopar]

I understand the RTE circuit board has to be swapped into the OEM Sender can
My question is after installing the RTE sender will the OEM tach work if I take the feed from the MSD box instead of the coil

 

[Billccm]

Yes. The rt-eng.com circuit board will accept the MSD signal.

 

[TN Mopar]

Awesome Thank you!
I will order one
I am putting his Voltage limiter on my dash tomorrow

 

[Billccm]

http://www.average-guys-car-restora...ing-tach-for-68-road-runner-project-beepbeep/

This is the tach signal from my MSD

 

[RJRENTON]

Billccm,
Very interesting and informative presentation in your serialized postings. Being a registered professional Electrical Engineer, I really appreciated the effort. I'm reasonably sure that a large percentage of your audience had no clue as to what you were referring to and your methodology, especially with the traces on your Tectronix Dual trace 'scope and square wave generator, which is unfortunate, as it was very well done. I think that your audience is more "nuts and bolts" oriented (including me for a large part) than in theory of why or how something works. Paraphrasing an old axiom: ...."if its broke, l just want to know how to fix it..."
This is just my opinion of course.
Bob Renton

 

[bcOH67]

Thanks Bob and Bill for your help! I have no ties to MSD persay, it was just installed in the car when I bought it and I'm just trying to make what I have work. (I don't know anything about starter systems good or bad) If there's an easier system to have that sure starts every time and works easier with the gauge cluster I'm all about hearing about it. Thanks again!

 

[Billccm]

So the reason why I went to the trouble of 'characterizing' the TACH with MSD is due to the misconception that you need the MSD TACH Driver converter. The short answer is the factory TACH needs the rt-eng.com upgrade and that is all for operation with MSD (and most other electronic ignitions except the Pertronix III). I email MSD multiple times and the best answer I got was 'you might need the tach driver'.
The answer no one could give me was what is the TACH SIGNAL from the MSD box? Is it a nice square wave with good edges, what is the Vp-p, and how does the factory tach behave with MSD?
I had an email dialog with rt-eng.com and they are great guys and engineers themselves. We shared a few waveforms back and forth and they told me about how to determine if the tach movement was good for their PCB conversion (1.5V D cell test). I still can't say enough good about their products.

 

[RJRENTON]

http://www.average-guys-car-restora...ing-tach-for-68-road-runner-project-beepbeep/

This is the tach signal from my MSD

Bill,
Again, a real well presented explanation....but...with one exception......ive seen better looking legs on Grand Pianos...... (ha-ha-ha!!!!!)....just joking...
Bob Renton