Hello everyone,

Getting ready to tackle my T5 swap... A little unconventional here...

I have a 350 TPI, 88 GTA, factory auto, digital dash.

I am going to use the Hawks billet adjustable hydraulics, Centerforce Clutch, stock flywheel... I also have a set of manual pedals, Thirdgen guy firewall brace, pretty much a fully built kit. Running a WC T5 transmission.

Questions
1. Since my computer is tuned for an auto, what do I need to do in the computer department? Will I be able to start the car as is? Will the car think its in park by default?
2. Is it possible to get my digital dash tachometer to work? I have a 5500 rpm redline tach, which If i remember correctly is the right one for a 305 tpi 5 speed car. Am I better off just going with an aftermarket tach? My donor car was a cable driven tachometer signal from an 88 camaro, but I know the digital dash is different.

 

really a cable drive tach ? I thought that was only a old Vette thing
as far as tuning goes idle speed change, slight timing and iac logic. Many have used an automatic tune in a manual might see how it works. A Vss signal to the ecm is a must .

 

Yeah, There was a cable going from the rear of the tailshaft going into the back of the speedometer housing. Maybe that is something different.

 

http://www.atrol.com/cablex.htm
or a gps version . To convert the Vss so the ecm will see the signal get a Vss buffer or probably better a Dakota digital sgi-100bt.
I think you are referring to a Vss vs a tachometer.

 

Got that backwards, if the t5 going into a non cable drive instrument cluster car. You should call jags that run for a retrofit Vss and get the Dakota sgi-100bt.

 

Sure is. Definitely not the tach. That's ... the speedo.

T-5s with electric speedo use a "bullet" looking sending unit that goes in the same hole in the transmission. Uses the same drive gears on the transmission's mainshaft as cable speedos do. The gear on the sending unit is different, butt has the same # of teeth and whatnot, that a cable-drive speedo one would have had in the same situation (rear gear ratio etc.). The right SU and gears are getting tough to find these days, not least because there never were very many to begin with. Not impossible, just, not easy. Butt with the right ones of those your speedo will work fine and even read right, or at least, as right as it can; the driven gear has around 20 teeth on it more or less depending on your exact rear gears, so the smallest "step" you can make in the speedo reading, is about 5%. Still, that's usually "close enough", considering all the OTHER sources of error and variation, such as tire size (just the wear from new to bald is on the same order of magnitude, let alone air pressure).

None of that is any different for the digital dash from any other kind.

The tach doesn't give a rip what transmission is in the car. If it works with the auto, it'll work with the manual, if it's left hooked up and all that.

 

Ok, Great feedback from you guys. I appreciate you guys taking it easy on me too. I'm a young buck, and this is still a little new to me. Building a car solo in my garage and trying to figure out what will work and what won't. I had thought about just not using the Digital dash and going with a custom setup of Speedhut guages, I ran those on a previous build and the GPS speedo was quite accurate, and tach signal was fed off of the ls style coil pack. Not sure how that would translate in the small block world. But I do love the look of the original dash, and would love to make it functional if at all possible.

 

Here is how I converted my friend's digital Speedo from cable transmission without a expensive hard to find sensor

https://www.thirdgen.org/forums/transmissions-drivetrain/787717-1986-trans-am-700r4.html