i have a91 vette- thats the easy part- with a 434 small block and a th350 auto trans with a gear drive speedo on the tail shaft of the trans.how can i get this to work on a stock vette dash panel, or will i have to go with a mac. drive speedo at the dash, any help please

 

I've never needed to accomplish this personally but I would think it not difficult. Is it a Chevy style (5/8") "output" or a PBO style (1 1/2"). If it's the larger you could use a conventional Corvette TPI speed sensor with the correct tooth count gears installed. I suspect it's the smaller "bullet" style so I'd suggest these people, and look at #3 in the illustrations here:

http://www.jagsthatrun.com/Pages/Spe...eedometer.html


There's some very good reading and I've suggested them to friends with some unusual requirements. There's other vendors but these guys "understand" what they sell! That alone is a good reason to avoid the lesser vendors.

Your problem might be actually be coming up with a tooth count for the drive/driven if you've got a "bullet" style. The shorter tire and axle ratio combinations of Corvettes don't lend themselves to the tooth counts available.

You might need to accomplish the correct ratio with an adapter and then use one of the available "electronic" sensor from them. Space then could become an issue so you would need to mount the ratio adapter remotely with a short cable then the "electronic" adapter!

Post your axle ratio/tire size/style of "output" and if you know the tooth count of the drive gear it also. If you don't know the tooth count post the color!

I wouldn't think this a "difficult" solution! I understand the ratio requirements if it can't be done with a production drive/driven gear combination.