When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Hey guys I'll make this story as short as possible but-
I have 87 trans am gta, with 350 tpi and 700r4 transmission. I had a ton of work done to the car restoring it and it still needs to pass mechanical inspection. The speedo will not move and the guys at the shop told me I needed a new vss. So I bought one (very hard to find) gear driven, electronic vss. Used that came off a working corvette. Still didn't work, they told me I need new speed buffer, bought one didnt help, bought another one thinking that one was blown, didnt help.
These guys told me they couldn't fix it without those working parts and offered me no alternative. They dropped my car off and told me they cant work on it anymore lol.
So I ended up ordering a kit to convert to mechanical speedo on the tranny, digital dash and a sending unit that converts that analog signal Into electronic. But the issue I'm having now is I'm reading without the actual vss my transmission will not know correct shift points and perform horribly ? What can I do to get around this predicament?
I have a fuel injected crate 383 stroker engine almost finished waiting to be dropped in and I'm pretty stressed out over this. Obviously I am not a mechanic and alot of this stuff is new to me. Thanks for your help
But the issue I'm having now is I'm reading without the actual vss my transmission will not know correct shift points and perform horribly ? What can I do to get around this predicament?
Good afternoon Bonjorno (Or should I have said good morning ) ,
To keep it short & sweet , The only thing in your transmission that is electrically controlled is the torque converter lockup feature , ALL other shifting is 100% mechanically controlled . And there are aftermarket kits to control your Torque Converter Clutch in the absence of the car's normal ability to do so .
Ok thanks so much ! I was reading vss post after post and could not really get a clear answer.
I will be getting a new torque converter to match new engine camshaft anyway. I appreciate the quick response !
Just remember , if you want that new torque converter's lockup feature to function you'll need to look into one of those kits (if the VSS thing doesn't work out for you) . Depending on the car's intended use (racing or lots of in town driving VS extended highway trips) you may or may not care whether it functions or not , and from all I've read you won't harm anything driving without the lockup being functional (Just make DAMN sure you have the transmission's throttle position cable set correctly , if set wrong that WILL destroy your transmission in very short order) ....
If you want to see the electrical controls of the torque converter clutch solenoid in all their glory check out my sticky thread at the top of the page "Pictures of every component of a 700R4"
Yikes !!!! That's pricey , but yes indeed that would properly control your lockup converter as a stand alone function with no ECM control (cause it's missing it's VSS , for ex.) .
Now , here's my next worry for you , and something I don't know the answer to ;
Does the ECM use the VSS to tailor the fuel percentages and spark timing for different engine loads based on road speed ? And if it does , how much of a performance loss will you suffer for the ECM not knowing how fast the car is going ? You need to ask that question of a "tuner" , someone who knows the ways the ECM controls the engine based on what inputs , whether or not the VSS is important to how the engine performs at different vehicle speeds .
That price is canadian of course. And that's a good point, I just looked it up. My engine will run off a fi-tech self tuning fuel Injection system. As far as I can see it doesn't run off anything to do with a speedo. Says it runs off an MAF sensor
Good afternoon Bonjorno (Or should I have said good morning 
) , 
Yikes !!!! That's pricey , but yes indeed that would properly control your lockup converter as a stand alone function with no ECM control (cause it's missing it's VSS , for ex.) . 
Now , here's my next worry for you , and something I don't know the answer to ; 