I did the T-56 swap last year on my 88 TPI 350 camaro. The car has a stock engine with 32,000 original miles on everything. I put new plugs, wires, cap and rotor, fuel filter, and oxygen sensor in the car about 1,000 miles before the swap and the car always ran great. After the swap the car idles like crap when the engine is cold and of course I get the code for the VSS after a couple of minutes. My gas mileage also seems very poor too. From what I've read on here you can use the stock computer without any issues. Is that true? Or maybe my problems come from not having the speedometer hooked up? If anyone had similar problems after the automatic to six speed swap and solved it please let me know.

 

Your car needs the VSS hooked up for it to work properly. Shitty part is you have a mechanical speedo

 

i have a t56 in my car, and the guy who i bought it from did the tuning, he's damn good at it too, and then i had some electrical issuse, my speedo was saying i was goin 20-50 mph when i was stopped, i had a power wire too close to the vss wire, and when i was troubleshooting it to figure that out i called him up, and he said the car is not gonna run as well if the vss signal is being affected by something, so if yours isnt hooked up at all i assume it could be a problem based on what he said

 

When I lost my speedo cable my engine idled poorly, stalled at a signal, and my mileage went way down. Same problems you are having.

There are several ways to get your speedometer working. One is a Cable-X box, second is a new tail housing for $750, or lastly machine the tail housing for a mechanical speedometer drive. I'm going with the last option since I can do it myself.

Here is a link to the Cable-X box.

http://www.abbott-tach.com/Cable%20X.html

 

OK so if I hook up the Cable-X box and get it working properly that should solve the issues with my car not running quite right. Is this thing easy to wire up? Thanks for the replies.

 

According to the website, there is hot, ground, and signal. When I fixed my speedo cable my problems were cured. So I'd say if the problems you are having are related to no speedo and no signal to the computer, then yes it should clear them up.

 

where is this vss sensor iv got the cable driven speedo so i thought it wouldn't have vss ?

 

I believe it's on the back of your speedometer in your dash cluster.

 

Yes sir, it's a small yellow box marked 'AC' IIRC.

The price for that cable converter is a little bit steep however.

 

aah now i get it i was expecting it to be on trans somewhere so if i go with the after market speedo ill keep having problems. well back to the drawing board. the cable x box is cheaper than the tail shaft mod but both are too steep for me so ill keep looking

 

I realize this doesn't help your plight any, but that's precisely one of the reasons I decided to run the Tremec TKO instead of a T56. The TKO only requires a Ford to GM mechanical speedo adapter that Fortes Parts Connection sells for under $100. It's an expensive PITA to adapt a T56 to work correctly with the mechanical speedos. Those Cable X boxes pop up for sale used in the classifieds here every now and again. If you're lucky, you might be able to snag one quite a bit cheaper than new if you check the classifieds often.

 

OK so now I got the x box in today from abbott. I dropped the steering column and I also took apart the trim around the gauge cluster. How do I get the speedo out to get at the back of it? I have the plastic shield and all that stuff in front of the gauges off so I can actually touch them but there must be something in the back thats holding them in. I'd like some advice from someone who has done this before because I don't want to end up breaking this cheap plastic trim GM used just because I forgot to loosen some hidden screw.

 

 

Couple of hidden 10mil nuts down in between the idiot lights are most likely your problem.

If you've got the gauge panel loose, but it seems snagged on something, you probably forgot to unplug the speedo cable itself. It has a very annoying clip that's hard to get to, so use a long screwdriver, and come in from under the dash..

 

The speedo cable is held on by a spring loaded clip right where it goes into the back of the speedo. If you push the clip towards the back of the instrument cluster while pulling the opposite direction on the speedo cable, it should release. Like the other guy said, sometimes a long screwdriver makes it easier to undo, but I can usually manage to barely get a finger on the clip and press it down. Also, as mentioned above, there's two 10mm self-threading nuts that are located in the bulb sockets down where all the idiot lights are in the cluster. Once you get the 2 nuts out of the way, you should be able to pull the cluster towards you far enough to be able to reach the speedo cable clip on the back side of the cluster.