I have bought a 1985 Z28 Camaro and i am a little confused.
All the infomation I can find Tells me there is no Z28's with 305 TBI motors and manual transmissions but i appear to have one.
I am also trying to find a correct diff ratio for this car.
the VIN number is 1G1FP87F2FL103516.
some idiot has also replaced the console lid at some stage and the service parts id lable is missing.
The code stamper on the diff is 8 JC C 333 1.
Can anyone help me

 

All the infomation I can find Tells me there is no Z28's with 305 TBI motors and manual transmissions but i appear to have one.

I need a clarification on this before I comment. TBI? In 1985, the standard no-cost engine in the Z28 is the 305 carb (RPO LG4) represented by an "H" in the VIN (8th digit). The optional engine is the 305 TPI (RPO LB9) represented by an "F" in the VIN.

It is true that the 305 TPI only came with an automatic transmission in 1985. Also true is that the 305 carb could be gotten with either the 5-speed or automatic.

Since your VIN displays an "F" as the eighth digit, it was originally a 305 TPI with automatic. Since the 305 TPI with 5-speed was not produced until 1987, it would be impossible for your car to come equipped this way originally.

The code stamper on the diff is 8 JC C 333 1.

This decodes as:

8JC = 3.42:1 Open Differential
C should be a G = Chevrolet Gear and Axle Plant
333 = 333rd Day of the Year
1 = Day Shift

 

Sorry about the typo, it is a TPI not a TBI.

Thank's for the help on deoding the Diff.

 

1985 was the 1st year for TPI on the F-body....
there are alot of people here w/ 85' TPI cars, myself included.