Has anyone tried a vss from 90-93 corvettes in a 1984? Didnt they still use the 700r4 at least the 90-91?

 

Fits the trans perfect but it doesn't work with a 84 computer

 

You can use any VSS from '84 - '90 as long as you use the one configured for the correct tooth count driven gear. A "white" VSS should be stamped at the connector 34-39 and a "black" VSS should be stamped 40-45. The connector is centered in the VSS. The later VSS does NOT have a "centered" connector and is NOT correct.

 

Booo just what I was thinking it mat be.

You can use any VSS from '84 - '90 as long as you use the one configured for the correct tooth count driven gear. A "white" VSS should be stamped at the connector 34-39 and a "black" VSS should be stamped 40-45. The connector is centered in the VSS. The later VSS does NOT have a "centered" connector and is NOT correct.

How do I tell if mine is white or black 84 auto. Only after it comes out? Couldnt see any numbers on it.

 

'90+ VSS has a 4000 pulse signal,
'85 - '89 has 2000 pulse so I suspect his earlier CFI is the same ?

 

I can assure you that the VSS from '84 - '90 is the same! There's many misconceptions and some bad info that's been passed on for years by many.

OP - the 34-39 and the 40-45 is cast into the VSS at the electrical connector in the center. I believe it's on the side opposite of the "catch" for the connector.

 

I agree that this is correct. All 4 pulse sine wave, and converted at the dash to 2 pulse square and sent to ecm, and cruise. I have been reborn on this issue.

 

"MrWillys" - hello haven't seen you in a while!!

Here's I think an image of the "white" 34-39 tooth count VSS. The "black" 40-45 would be "black" where this one is white, aside from that they have exactly the same physical appearance.

 

Thanks then I have the white one.

And by the way I prefer to be referred to as her rather than him

 

A man of your tuning ability should know the differences

The 90/91 '727 (and identical '730 ) MAP ECM's have a 4K VSS input direct to the ECM which is then outputed to the other systems requiring a speed input
;not from the cluster to the ECM as on earlier TPI cars

http://tpiparts.net/1227730_pinout_diagram

 

Yes, I'm aware. Where I was confused was 84 through 89 which gets converted at the dash. Because I deal with so many conversions I assumed the 7165 received its 2 pulse from the VSS, when in fact I was wrong. WVZR-1 plumbed me up a few weeks ago.
We all take pride in understanding these systems, and I had been giving bad advice. The older transmission can be feed directly to the 7730, and 7727.

To the OP Toni:
We should have caught the I in Toni. Probably just makes us like you more?

 

Hello Toni - I believe that all '84 cars used the black VSS because of the axle ratios that were available for '84. Why yours would have a "white"? A previous owner needed one and couldn't find "black" and elected to do a modified install that's talked about frequently OR maybe the rear axle ratio was changed and the VSS and the driven gear were changed for the speedometer correction. Which? Don't know and it would likely be difficult to confirm.

The more simple "confirming" operation would be to lift the rear wheels and with one rotation of the rear wheel the drive-shaft will rotate something very close to 3 times indicating it's still a 3.07 ratio as built. Something other than that more or less would need noted.

Was maybe a used transmission installed and the VSS just came along for the ride from the used transmission? That's likely also.

Did I read in another thread that yours is actually "not connected"? Maybe you could explain?

 

The pins that the connector plugs on to are broke off on the vss motor itself. The connector that plugs to the motor was laying on top of the exhaust pipe I pulled it loose but I dont know if its melted bad to the point it cant be reused or not. I was under the car when Firestone was checking the steering rack.

 

That being the case you know you need one and likely also a connector that is no problem BUT first rather than assume anything the axle ratio needs confirmed. Had you mentioned yours was black I'd have no issues mentioning just get a black but there are a couple issues. They've been discontinued for quite sometime and when they're available they can be expensive. so also can be the white!

The tire rotation and counting the drive-shaft revolutions needs to be next. I don't believe there's any alternative. Both rear wheels need to be off the ground because of the locking differential. Rotate the rear wheel 1 full turn and count the drive-shaft revolutions.

Judging from a couple of your other posts I believe you can handle that! Did you conquer the 02 issue?

Any questions?

The more probable results of your "rotation confirmation":

3.0 + would be the 3.07 and expected, 2.5 would hint a 2.59 and a differential change, 2.75 would hint a 2.73 and a differential change. Now once that's solved then it becomes an issue of the number of driven teeth on the VSS when you remove it, that number needs to be confirmed for the axle ratio you find and the tire size that's on your car presently confirmed. I'd suggest one thing at a time. Ratio confirmation first.

 

I dont suppose there would be an id tag on the rear end? I saw the vss once when it was out and didnt see a gear on the end just a d shaped shaft.

http://imageshack.us/photo/my-images/69/0qlk.jpg/

 

This is a good list that shows vss's and gear ratio's and drive gear tooth counts.

http://www.corvetteforum.net/c4/vett...Gearshtm.shtml

 

If there were no gear on the D-shaped shaft then it wouldn't have been functional. The speedometer/odometer would not work.

I somewhat assumed this was maybe a recent purchase. Is it? Has the speedometer/odometer worked in the past.

A tag on an '84 differential no and I don't believe it was etched into the housings either. The correct gears that are used on the VSS have become more difficult to obtain so between the hard to obtain VSS and the also more difficult to obtain gears the more that's done to confirm the better. If you wanted to just assume, the car would need the most difficult to obtain "black" VSS and a 42 tooth gear if the tires are still the 255/50-16's. What is the tire size now?

 

There are documented errors in that listing

http://forums.corvetteforum.com/1579556738-post4.html

http://forums.corvetteforum.com/c4-t...-54-gears.html

 

I bought the car at the end of July this year.

The tach works no speedometer or odometer.

Would the gear be on the metal shaft after it came out of the car? And go on the shaft before it goes back in? I dont see what would hold a gear to the shaft. I would think the gear stays in the transmission?

 

The gear remains on the D-shaped shaft with no retainer needed. It can't under normal circumstances come off once installed, the mesh of the two gears keeps it secure. If you've removed the VSS and there was no gear then it wasn't there at all.

The mesh of the gears is like this BUT this is for a "cable driven" unit, yours is identical with only the VSS replacing the cable driven in the image.