So I just bought a th350 that’s rebuilt for a good price so I figured it was worth it, is there a way I can make the electronic speedo work with the transmission? Like an adapter or something? Or do I just need to get a manual cluster? Sorry if this has been answered before somewhere, I looked and couldn’t find anything super solid.

 

What do you have for a car?

 

it’s an 87 Firebird formula, definitely has the electronic speedo wire. Sorry for not mentioning what the car was lol

 

Don't take this as gospel...from what I'm reading T5s and TH350s share the same speedo pieces...
https://lugnutz65chevystepside.weebl...binations.html

 

I used this on my '89 to convert the mechanical speedometer T5 I installed to the firebird electronic speedometer.

Pretty sure both transmissions use the same "bullet" style speedo gear holder thing. You'll have to figure out the needed gearing changes to make the speedometer accurate though. Or you could intercept the signal with one of those dakota boxes and calibrate it that way.

https://jagsthatrun.com/products/speed-sensor-4pac

 

I saw the Dakota boxes but they’re really expensive lol, so essentially I could just buy a t5 electric speedo adapter? How would I calibrate it?

 

Problem is I have the electric speedo, so I guess I could just change to a manual speedo and then it would hook up?

 

the Dakota sgi-100bt is cheap. Summit racing has instructions on their site. But with a th350 swap gears to calibrate a retrofit Vss from Howell or jags that run would be the easiest . Just curious are you fabricating your torque arm mount or find an old B&m kit ?

 

I found a crossmember on summit that was recommended on here that has the torque arm mount on the crossmember. So I was just going to buy this https://www.summitracing.com/parts/upi-2230-r
Honestly I have very little knowledge on the Speedo stuff so I’m still kind of confused lol, the Dakota box just calibrates it right? I would still need something that turns the gears into an electrical signal? And I don’t really understand the Howell thing, are you saying it would be easier to buy a different vss and swap the gears in the transmission to make them work together?

 

https://jagsthatrun.com/products/spe...ce-holder-4pac

instead of a sgi-100bt calibrate with drive and driven gears.

https://www.ebay.com/itm/13271107799...mis&media=COPY


https://www.tciauto.com/speedometer-gear-calculator

 

so a couple questions on that, the jags that run sensor says it for tbi cars 85-89, but mine was carbureted, and I’ve since engine swapped it, but I don’t think the swap matters, and where would the drive given gears go? Inside where the speedo hooks up to the transmission?

 

I would guess the vss is 2k ppm. Might call jags that run to confirm. The drive and driven gears go in the transmission tail housing. Same spot the retrofit vss hooks up.

 

Should be a 4k pulse. That's what mine is.

 

You want this one. The 4k vss.

https://jagsthatrun.com/products/speed-sensor-4pac

The 2k will not work as the poster in this thread found out.

https://www.thirdgen.org/forums/tran...-vss-help.html

 

Iirc , if you have a vss buffer box you would want a 4k ppm.

 

so would I have to actually open up the tail shaft to change them out? Or can it just unbolt or something like that from where it hooks up?

 

Depends on the drive gear count if it can be used. The bullet for the driven gear has a bolt holding it to the tail housing. If the drive gear needs to be replaced the bullet driven gear gets removed then the 4 tail housing bolts. Or as stated use a sgi-100bt to recalibrate the signal. Even with calculation of gears it could be slightly off in readings.

 

so essentially get that vss thing either way and then either get the new gears or the Dakota and use that to calibrate it to read correctly? And it sounds like the Dakota would be more accurate?

 

Yup

 

alright thanks a lot for the help!