I need some ***istance in hooking up a speedometer. For reasons not really necessary to the thread, I used a special tranmission (originally with a top shifter) in my 1974 GTO because of the gear ratios in the transmission. When a side shifter was attached to the transmission, the shifter is in front of the speedometer take-off. We have played the 90 degree adapter game; it won't work, there is insufficient space. So, options I can think of: (A) change transmissions - DON'T wish to do this (B) digital aftermarket speedometer - DON'T wish to do this either (C) memory (not good) says one of the large cars drove the speedometer cable off of the left front wheel ***embly back in the 50's or early 60's, but cannot remember which one. Anyone? (D) Any other method of driving the speedometer cable (wish to retain original speedometer)? Have calibrated tach readings to speed, which works for me; but others wish to drive the car. Really need a functional speedometer. Jon.
VW and late 60s Oldsmobile full sized cars used the wheel driven speedo. As long as the tire is the right diameter, it'll work. Let's see....1000 turns/mile, 5280 ft per mile, 12" per foot, 3.14" cir***ference per diameter, equals 20 inches. That can't be right.
Thanks Jim, could not remember what make used the wheel drive. Will try to find a late '60's Olds illustrated parts book, and see how compatible it is with Pontiac. Recalibration of the speedometer is not a problem, once I get something to drive the cable. Jon.
The Olds full size cars used a 5 on 5 bolt pattern on the wheels...a 74 GTO has a 4.75" bolt pattern. I suppose you could redrill the olds hub or use a chevy/GTO hub but it won't have the speedo drive.. BTW, my 69 Olds full size had the wheel driven speedo.
My 1969 Olds Delta 88 has the speedo driven off the front left wheel. The cable is fed through the center of the spindle. I can't remember how the cable is tied to the rotor though. I think it was through the center cap.
Way beyond my abilities, but I know a lot of people here could do this well: ***uming the tailhousing is not radically asymmetrical, cut out the chunk with the drive in it, rotate it around to the other side of transmission, use the gears themselves to do the spacing and weldit back in. Add longer cable to compensate new angle and location.
Are there other tailhousings from different vehicles that fit the transmission? I know they had the speedo cable come out in some interesting directions on some of the Fords
Ran into same kind of problem gage to the ******. gave up trying to figure it out myself . Went to local ****** shop told the owner of my tail of woe and he said sure all you need this adapter handed it to me it was like 6 bucks. I should have asked someone who knows sooner.
Transmissions are not my thing. Got a good friend who builds transmissions to look at it. He had never seen this particular transmission before. I used it because of the gear ratios. Have an aluminum flywheel, so need the very low first gear. He didn't think any other tailhousing would work. And the adapter won't work either, tried that already. The Olds front wheel cable drive sounds worth looking into. And the tailhousing is asymetrical. As many of us have learned, one modification begets five more. Overall, VERY happy with the car. Runs exceptionally well, and even doing breakin type driving, right at 20 MPG. Just ironing out a few bugs. Jon.
Hey, the only need for a speedo is so we know when we are going too fast, and we PAY the police to tell us when that happens. No need for the thing at all.
If it is only other that you are worried about - the GPS sounds like the easiest option. You can also use a bicycle speedometer, magnet on rim (rear) and receiver on backing plate. Easy-peasy calibration on most, and you've a speedo. Cosmo
I was going to say Olds as well. I had a '73 that I think the speedo was wheel driven. I don't know about before that.
My 1965 Olds Starfire (425 cui plus th400) had the spindle driven speedo too. I'm still not sure how to fix that problem on my truck...
There is another, slightly whacko, solution out there if there is enough clearance for the digital speedo sender you don't want...someone out ther makes a Rube Goldberg sounding device to drive a traditional speedo from a digital sender. It can be found on sites that sell stuff to put 200R4 and TH700 transmissions into early Chevy musclecars... It is apparently an electric motor to drive the speedo, speed controlled by digital input by the later GM senders. My jaw hangs in amazement that this exists and is said to work...
The mid 60's Oldsmobiles ( Cutl***/442 ect ) also had the front wheel speedometer drive. I believe a mid size Olds spindle would be a LOT closer fit than the full size models. Some owners with the Novas ( same basic front end as your GTO ) use Chevelle spindles to get disc brakes ... so the Cutl***/442 might be a closer fit. .
A little ouside the box thinking, is it possible to relocate the shifter enough to clear the speedo drive location ? Move the body of the shifter forward or back (whichever is possible) and then compensate for the lever location with a differently shaped lever, linkage etc.? Maybe a little fabrication involved but the speedo drive issue would be solved.
Thanks to all who have offered suggestions. The mid-size Olds front spindle sounds like the avenue to approach. We should soon have a killing frost in Missouri (gets rid of the varmints like yellow-jackets, spiders, etc.) and I can then investigate some of the local private salvage yards. Of course, with my luck, Olds will spin the cable the opposite direction from Pontiac. Started this project in 1984. Wouldn't want to finish it to soon; then I might have to start something else. Jon.
No they didn't. Only the mid 1960s full size cars used the wheel-driven speedo cable. Those spindles won't work on an X-body (1974 GTO). Just get the correct tailhousing or adapter. There are many options out there.
My friend had a 66 442 ... and the speedometer drive was off the front wheel. I had to use Chevelle speedometer drive transmission parts on his 442 4 speed ... when I installed it in a Chevelle
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