86 Silverado Father and Son project

[mcbassin]

Originally Posted by rfmaster

Mike

You'll need the following:

Speedometer Driven Gear (43)
Speedometer Housing & Support Bracket (44)
Speedometer Housing O-Ring (42)
http://www.tcsproducts.com/images/st..._schematic.pdf

All three items can be sourced from JY. The only catch is get a correct driven gear that gets speedometer cable to turn at 1000 tire revs/mile - this is straight forward and several handy references are availlable. The following links are will provide you with a good reference information:

Look for part # 54 (P)

http://www.partshp.com/speedometer_gears.htm
and
http://www.73-87.com/7387garage/drivetrain/speedo.htm

VSS
I think I covered this subject extensively in prior posting.

Attached photos capture my setup - I run this my conversion. That yellow module is a JTR 2000PPM TBI VSS bolted to speedometer housing and speedometer cable is bolted into VSS output. Photos were taken at an awkward angle - sorry.


//RF

RF,
I was about to order that inline vss like yours when I looked at links you posted about the speedo gears. I know you have covered this before about the the rear end gear ratio and tire size need to be known before you know which gear drive to put in the tranny. So my question, why not just change the speedo from a later model truck? they are readily available at the pull-a-part. The car vss can send info to the ecm and there should be a wire that sends info to the speedo right? It seems like you might even be able to reprogram the eprom to cover tire size? I really don't know what the truck gear ratio is or what size tire we are going with yet. I just don't want to order a bunch of new parts and then go with larger tires and find out the speedo is wrong. Thanks for your help,

Mike