LT1/T56 Swap: Speedometer, Mechanical or Electronic?
 

As some of you are aware I am in the middle of this swap and am curious which is the best/easiest/cheapest route to go with when addressing the mechanical guage to electronic tranny issue. I know you can fix the tranny to run off the speedo cable for about $300. So far that seems to be the cheapest way to go. What are you running in your LT1 3rd gen.

Re: LT1/T56 Swap: Speedometer, Mechanical or Electronic?
 

We converted to Autometer gauges to run all electric on my friends 82 Trans Am LT1/T56 setup. We had the Mech to Electric Speedo box (probably the same one you are looking at) and decided that $300 would be best spent on new gauges, so we sent that box back. all the gauges came to around $500 I think and that included 2 for the pillar pod as well.

here is a shot where I was in the process of wiring up the gauges, (car had a 4L60E in it for about a month till we converted to a T56)
http://www.transamws6.com/pics/82_ta/mm1car2 014.jpg

and here it is done,
http://www.transamws6.com/pics/82_ta/mm1car2 015.jpg

Re: LT1/T56 Swap: Speedometer, Mechanical or Electronic?
 

Send me a link on where you purchased the guages. I've been considering the very same guages but I've priced them at $750. Let me know where he got them. thanx.

Re: LT1/T56 Swap: Speedometer, Mechanical or Electronic?
 

Ok maybe you all can help me to i'm considering the LT1 swap into my third gen. I would be getting the LT1 and auto tranny together. What all would i need to do to fuel system,wiring harness,gauges?? I'm clueless on the swap it was suggested by a friend. Because i wanted to TT my 305TPI he suggested the LT1 swap.

Re: LT1/T56 Swap: Speedometer, Mechanical or Electronic?
 

the gauges were all purchased from Jegs back in 2002. www.jegs.com
Speedo and Tach were about $300 or so for the pair, and the others were about $30 each except for the A/F gauge which was about $45.. I think we chose the sportcomp series.

With the current prices, they total up to $576.92, without the Tranny temp and A/F the total is $484.94

Remove
Speedometer, 160-MPH, In-Dash Mount
Part Number # 105-3989
$189.99 $189.99

Remove
Tachometer, 10,000-RPM, In-Dash Mount
Part Number # 105-3990
$134.99 $134.99

Remove
Fuel Level, 0-90 Ohm (GM 65-Up)
Part Number # 105-3314
$33.99 $33.99

Remove
Oil Pressure, 0-100 psi
Part Number # 105-3327
$49.99 $49.99

Remove
Water Temperature, 100° - 250°F
Part Number # 105-3337
$39.99 $39.99

Remove
Air/Fuel Ratio (Lean/Rich)
Part Number # 105-3375
$51.99 $51.99

Remove
Voltmeter, 8-18 volt
Part Number # 105-3391
$35.99 $35.99

Remove
Transmission Temperature, 100° - 250°F
Part Number # 105-3357
$39.99 $39.99
Update

Subtotal: $576.92

Re: LT1/T56 Swap: Speedometer, Mechanical or Electronic?
 

http://www.gmhightechperformance.com/tech/0409htp_snow/

That says it all. I ordered my kit from Pure Choice and received it today actually. You'll need 35 inch lines, and the 16mm and 14mm fittings. My total was $120. I know you can do it a heck of alot cheaper, but it looks good, it's pieced together for you, and it looks great.

Im definately going to look into the speedo swap. But I still have a question. Do I need an input going to the PCM to make the tranny work properly. I know I would if it were an Automatic, but Im unsure about the manual. Was there any cutting required to get the guages to fit. If so how much and how difficult alltogether was the installation.

EDIT: 91 1le: Your guages are already electrictronic. As far as the wiring harness, go to thirdgen.org and search "LT1 wiring for dummies" and that is most of what you will need as far as wiring info.

Re: LT1/T56 Swap: Speedometer, Mechanical or Electronic?
 

Hi, I have an '86 Z with an LT1 & 4L60E trans and looked at many options for the speedo. The cheapest was just to replace the stock speedo with a Cyberdyne electronic speedo. It uses the speed sensor signal from your new tranny.
(Both; the auto and manual trannies use a speed sensor.)
The gauge also gives you 1/4 mile time, top speed, and a few other goodies.
http://www.cyberdynegauges.net/spedoprod.htm

If you want to see a picture of the speedo installed in the stock cluster, check this out:
http://img.villagephotos.com/p/2005-...es-Driving.JPG

(This car is for sale and listed in the "For Sale" section of this board -1986 Z28)

(Jeg's has the speedo listed for $120.00) It's very easy to connect the wires. The hard part was cutting out the stock plastic lens on the stock guages for a perfect fit.

Let us know how you solve your speedo problem.
Good luck!

http://img.villagephotos.com/p/2005-...ontcloseup.JPG