Does anyone have info about tach drive generators? My DeStoto hemi doesn't have a tach drive off the distributor and I want to use a cable driven Stewart Warner tachometer. I've found a lot of different tachs, old Ford and Case tractors, Corvettes, etc...I know setting them up, you have to have the right pulley size and what not to get a correct reading, any online sites or formulas would be great! Thanks guys!
alot of diesels used them as did marine situations dont know much more than that......I like that, thinking out side the box
http://www.pegasusautoracing.com/productdetails.asp?RecID=254 see what you did now.....you made me post
Eh, cool part, but I want to run it off the generator, I just need to learn about pulley reduction and stuff.
The problem you are going to have is that your SW tach was probably for a distributor drive and that is only turning half motor speed. A generator is usually overdriven from the motor speed. so you would need some kind of reduction gear to get it to read right. On a Stuska dyno that i used to own, it had a nice right angle 2-1 reduction gear. I don't know if they sell them anymore, because Stuska was bought by another company. You also might check with a speedometer shop to see if they have any information on these. If you come up with a plan and need some machine work done, send me a PM.
Stewart Warner sold several different reducers...search eBay. There's also kits to change the ratios...
Hamb member justplainj has one on his A coupe. It is driven off of the back of the generator. PM him he might help. .
Around 1963 Chevrolet had a drive cable off the back of the generator that ran the speed sensor for the cruse controll, is that what you are asking about?
a place in West Sacramento called Commercial Speedometer [FONT=Arial,Helvetica,Sans-serif]916-371-5873 [/FONT]can make any reduction box you need. Alot of customers of mine have used them when they have put in a mismatch trans to their speedo and there isnt a proper speedo gear to calibrate it right. If you figure out your pulley sizes for the crank and generator or wherever else you may hook it to they can definitely make the box to get it right as well as build a cable with the correct ends for the tach and the otherside.
The 58 Corvette used a tach drive generator. If you can find one of these $$$ you will have it all. It may be cheaper than fabricating end plates, modifying armatures and adding gear reducers to retrofit to a standard generator unless you just like the challenge of doing it all yourself.
Most any heavy truck parts store can make you an adapter. You don't need any modification to the pulleys. They can build you an adapter with any drive input to any drive output. and about any ratio you will need. All you need to do is do the math and tell them the ratio. Bring your generator and tach and the measure of the lenght of cable you need. The drive units come in a huge kit box that they pick the right pieces from. I think Alemite or Stewart Warner makes the deal. The units can also be done to reverse the rotation if thats needed. Last one I bought was about 60 bucks.
That is probably the same generator used on 58 Chevs with power steering. The pump mounted on the back of the generator, the armature had a splined shaft sticking out the back end. I think 59's used it also.
The Chevy generators for power steering from 55 through about 60 had the same shaft extension as the Corvette tach drive generators. The Corvette generators are quite expensive now but the power steering generators show up at swap meets often for very low prices. The only difference is the part number tag. The Corvette tach drive adapter is available as a reproduction but they are not cheap. You may be much better off looking for a truck tach drive adapter.
This is all good info. I knew about the power steering generators having the longer rear shaft extension, but I figured the tach dive was gonna be pricey for it. I'm gonna look into the heavy truck route and see what I can dig up.
One way to go is fit some modern VDO guts in the tach, they can run off of the atlernator, and are adjustable, or just hook it up to your distributor negative side. Seems like it may be the best route. Mark
Pic is of a generator/tach drive on a 354 Hemi on my Facel. I believe the drive is also the same on a 55-57 Chrysler 300 series.
Anyone ran a tractor generator?? My friends '60's, or so ford tractor has one Might have issues with RPM though, being a tractor turns low RPM
I sold a 60 vette Tach drive generator yesterday at PIR for $150. I had it for sale here HAMB for $200 for months, but no one was interested. No movement on it for $200 at PIR sold in an instant at $150. so value is dependant on the buyer.
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