87_TA

Need manual to electronic speedo converter..
Does somebody make one of these? That converts cable to electronic?

Thanks

sofakingdom

iTrader: (1)

GM

Just get a VSS from out of whatever kind of transmission your car has

87_TA

Thanks, but a th350 never came with a vss.....
thatsa why I need the cable to vss converter.

MaxxMitchell

iTrader: (4)

I just did a TH350 swap in my firebird, that used to have the 2.8 700R4 combo, with the Vss system. I put in the short tail shaft th350. Cool thing is the 700R4 tail shaft cover/vss sender/speedo gears all swap over!

Only problem was that the 700R4 tail shaft is actually 1/2" longer, so the Th350 output shaft sits inside the seal a 1/2" instead of being flush. I had to have a custom driveshaft made anyways. I made it 43.5" from center of yoke to yoke. That made it sit 3/4" out from the rear seal, witch is pretty close to the recomended 1", as I wanted to keep asmuch as possible yoke splines incontact with the output shaft.

The swap of the tails was SUPER easy, just be prepaired to lose .5-1 gallons of tranny fluid.


If you dont want to use OEM stuff, try https://www.speedscenewiring.com

The TBI unit is a 2000 ppm, and the TPI is 4000ppm I believe. So what ever VSS buffer box has to be the correct one. Then you could get gear sets to dial in the speedo, or get the DakotaDigital SGI-5
to really dial it in, and never take the tail shaft off again to account for gears/tire changes.

87_TA

Awsome info!
I heard years ago that the tailshafts would swap.. but nobody to back it up..
And gears swap over as well!! great! thanks

MaxxMitchell

iTrader: (4)

NP I didnt think they would with out swaping output shafts. Best thing to do is do it before you drop the tranny in, its kinda hard with it in car. It took me an hr or so to do it in car.

TABANDIT

This is what I did when I put a TH350 in my 1987 TA. I got the following parts from Dakato Digital. SEN-01-1 (found at Speedometer 8K Pulse Generator ) and then SGI-5 (found at Speed/ Tach Interface ). I have completed the instal yet, I melted a speedo wire on my exhaust and haven't hooked it back up yet, but basically the SEN-01-1 goes right into you speedo hole in the transmission, and gets spiced into your factory wire. You then hook the SGI-5 up to the wiring before it goes into the speedo, I'm going to do it just before it enters the gauge cluster. The SGI-5 is adjustable, so you just follow somebody at going at a set speed and then push a couple of buttons and it resets your speed. It will really be helpful if you change your tires for winter with smaller diameter ones, or if you ever change your rear-end gear, just a couple of buttons and your speed is recalibrated.

dwint

i have a 88 with a 700r4 this is cable driven,my question is with different tires and gears is there any way i could get this accurate without going into the tranny and figuring what ratio i need

87_TA

Figured I would try this as I pulled trans out for converter swap, And still waiting for the part Rrob recomended from parts direct.
The tail shaft housing is actually about 1.25" longer. I laid them on bench side by side.
It does fit, however my driveshaft is much to long for it.
I figured if its only 1/2, my D/S would be just fine.. Not the case..
Great option though, Also incase anyone did not know you can flip housings
180* also..

MaxxMitchell

iTrader: (4)

Ahh, well mine was only a .5" difference. I guess measure and check. Now my 700R4 tail came from the 2.8L 700R4 casing, so maybe thats the key.

dwint

i didn't make myself to clear on the last thread on the tranny and speedo.i am doin away with the computer and i bought the kit that it has to use a vacuum for the torque converter lockup so i thought i wasnt mechanical,when it comes to trannys i am lost so you tranny guys are probably lauphing at this but thats ok .all i want is a accurate speedo when i put the new engine in.what are these converters

dwint

i just called the company that sells these for $ 25.00 and they said it will work as long as i get a electric speedometer

1st3rdgen23

i have a quick question that is a little off subject but i can't find the answer anywhere. i have a friend that is plannig on putting an Lt-1 in his '91 Firebird but instead of using a 700r-4 he wants to use a th350. What his question is will the engine run w/o the wires that go to the trans being plugged in? And if not what must be done to get it to work? The engine and comp are out of a '95 Roadmaster.