OK fellas I know I can call someone's tech line and get this answer but I would prefer to hear it from you. I got this Joe Hunt mag that I'm going to run on a current project. I have run magnetos before but they have always had a tach drive and ran a mechanical tach. My Joe Huint does not have a tach drive. So how do you run a mag off of one? Is there some sort of electrical adapter that needs to be run? Do I hook it to the ground wire ppst or is it an internal thing that I need to do? Thanks
I ran an Autometer tach adapter on my vertex - it worked OK, but nothing to write home about as it was "jumpy" at the lower RPM's. Next time I'm gonna try a tach alternator in this situation. I forgot to add - it was all external.
Like HemiRambler said, but you got to have the right tach too. I believe the adapter is the same for internal or external coil magneto, tachs are different and gettin scarce. I might have an internal autometer mag tach layin about if you have a need.
Thanks. Unless you have everything up to snuff a mechanical has a tendency to jump around anyway. I thought about setting up a drive with a doubler off the end of my cam but that is probably a 20 dollar cure for a 10 cent problem. I'm not familiar with a tach atlernater?
I have a S/W I was going to try and set up, but if I can't make it work I'll drop you a note. Thanks for the offer.
You can always hook up a setup where it reads off the ring-gear like the diesels do. Theres all kinds of setups. You can run a magnet setup off your harmonic balancer that'll give you a tach feed. Dakota Digital and Assp-pro
What hemirambler mentions, is that he could attach leads to the external coil for his signal to the tach. Don't hook up anything to the ground post on the outside of the mag housing, besides a ground wire. That is just a direct link to you points and the base plate. I bet you could call Ted at Vertex and he could lead you in the right direction.
The Joe Hunt is a vertex mag no external coil. I saw a car in a magazine the other day that had a mechanical tach drive off the back of his generator. Supposedly an old corvette thing. I run an electric fan and an electric pump so I don't think I'll look for one of those setups. I just figured there must be a simple setup.
Look around for a generator for a Ford tractor, many of them have the external tach drive off the back of them. Also look for Lucas tach drive generator, they run about 45.00 new on Ebay. if you can put up with the Lucas stuff and deal with 30 amp output all should be good. The Corvette generator will run you $200-400.
I'll have to figure my amp draw. I guess I have no drain from my ignition so its just a matter of the other electrical components. The fan may kill me. I guess I could go mechanical with the fan of I fab a datona type of shroud ( its a long ways from the engine to the radiator).
Hi , I bought a Joe Hunt awhile back off of e-bay and it came with a little black box from Auto-meter they make for tach signal . I also picked up a Sun tach with a sending unit for a Mag that ran on a small block drag car . I 'm just getting aroung to hooking up the Sun unit . If no worky I'll try the Auto-Meter. Now I'll not sure about the solid core plug wires ! I'll try to let you know . Mike
Here's the problem, an autometer tach works on a 'square tooth' signal; mags have a 'saw tooth' signal because of all the capacitance; the early SW may take an altogether different signal depending on how old it is. Remember when tach were vehicle specific? What i got layin about is an old vertex with mechanical tach drive, if you want to swap bases thats ok by me.
Now you're talkin'. I'll do the research on my tach. I got an old greenline sweep. I keep a mechanical tach around as most of my dizzys are tach drive dizzys. If I can't make it work and keep it simple I'mm contact you with the swap. That would make life so easy and if I had a mag failure I could swap in a dizzy and keep on truckin'.
I had a Vertex on my GMC and just went to my local nearby Speed Shop (Gotellis) and bought an electronic tach for a mag. Yes it attached to the ground post.
I got an old Stude in the garage. Was a blown gas car, its becomming a naturally aspirated gas car. You could actually make the trekk across town if you wanted to.
You need a tach drive adaptor such as the one shown in the attached image. They're available in 1:1 and 2:1 ratios to run off the crank or camshaft, respectively. You'd probably need to devise a bracket, although, you might be able to find one pre-made. This one in particular is a new part and available from Pegasus Auto Racing, however, there are vintage parts out there, too. Check eBay, the classifieds, and the like.
Its still pretty rough (not very far along) and that's as close to an invite as anybody gets. PM me for my number.
About 10 years ago, when I got the Cerillo magneto for the Hemi in my vintage dirt car, I had the same problem. I found the solution at good ole' J.C. Whitney. They had a deal that clamped around one of the plug wires which connected to my Mallory tachometer. They also listed a digital tach that they said would work on anything. Since the were both pretty cheap (less that $50 total), I ordered them both. I took a little time and put the thing that clamped on the plug wire in a place it would be hard to see, and hooked up the digital tach. They both worked fine, and read close enough to each other that I believe they were both very close. Now the bad news, I just checked my latest J.C. Whitney catalog and they are no longer listed. I'll bet a Google search with the proper terms will turn something up, however. I don't think I've bought anything from Whitney for at least 5 years, but I still get a catalog or two each year.
The last I bought from Whittney was about '98 and it had been at least 20 years before that. They have been sending me a catalog at least once or twice a year since about 66 or 67 if I recall. They even find me when I move. I'll use all the info I have and come up with something that works. I'm getting a pretty good starting place here.
I'm sorry to dredge up an old thread, but I too have a Vertex magneto in a 1954 Chevy pickup truck, with a 261 cu in inline six engine (1959) and a McCulloch supercharger from a 1959 Studebaker Golden Hawk. The late previous owner setup the basic configuration and I'm restoring/finishing his work. I have had a Vertex magneto rebuilt and cleaned. I've now installed it and a new wiring harness, complete with a kill switch for the mag, (Joe Hunt did the rebuild). I also purchased from them the Magneto Tach Converter, since I'll be running a newer electronic tach. Has anyone used this box from Hunt for this purpose? I have downloaded the wiring diagram that comes with the converter and I'm still a bit confused. Here is what I think needs to be done..... Red - connect to a 12 volt switch power source Black - connect to vehicle ground Violet - connect to the input of the tach Brown/Black - connect to one side of the kill switch along with a wire to the vehicle ground Brown/Orange - connect to one side of the kill switch along with a wire from the terminal on the magneto Brown/Yellow - No need to use in my situation Does my interpretation of where the last three wires go correct?
The guys here love to help you, but few will go hunting the diagram. Make their life easier - include the picture. Diagram attached below. Cheers, Harv
Autometer USED to make a tach. just for the magneto (yeah, Vertex in my case) . I ran a small Chevy in a 50 Anglia, with this combination...for a SHORT time. When I originally got my car running, I didn't put a tach. into the car. A coupla friends kept harping on me to put a tach. in it. Autometer had come out with the 5" face tach to run with the mag....so I bought one. Mounted it at the bottom of the windshield, so it was easy to see. I was actually more accurate at shifting by the seat of my pants than by watching the tach...so...yeah, the tach. was removed ! Check Autometer to see if they still make this tach. Mike
I run a tach in the car for the friends I let drive it. If I feel it ran out of engine before the line then it would be a gear change.
I'd call Hunt and ask them, but my opinion: Red - connect to a 12V power source that switches off when the ignition is off. Black - connect to vehicle ground. Violet - connect to the input of the tach. Brown/Black - connect to the vehicle ground. Brown/Orange - connect to the "P" terminal of the magneto, or the terminal of the kill switch that is wired to the "P" terminal. Brown/Yellow - No need to use. Tape the end off, coil it up neatly and tuck it out of the way. Cheers, Harv
Harv, First thanks for the response. I'm with you up to connecting the Brown/Black to ground and the Brown/orange to the "P" terminal. The only terminal on the tach is the one that holds the "ground kill wire" The arrow in the photo below points to the terminal. Is that the "P" terminal?
The Jalopy Journal
