Speedometer gear for 4.88 Z/28 Camaro

[SMS]

When rebuilding my 68 Z/28 BV 12 bolt I put a set of 4.88’s in it just for fun. Now I have the transmission apart to freshen up and want to make the speedometer correct. I did all the math to figure out the two gears and adapter I need, but can’t find my notes.
Anyone have the quick answer on the drive and driven gear I need to find? Stock tire size.

Thanks,

Bill

[HuggerSS]

My 68 Z has factory “BX” 4:88 gears. I am not sure how many teeth the speedo gear is, but it is black. The shaft gear was not any different from other transmissions that I looked at. My car I has a factory speedo reducer. I am not sure if I was any help, please let me know if you need anything else.

[SMS]

Any chance you know the numbers or ratio of your reducer?

[HuggerSS]

6476735
1:824

[clnovaparts]

Chart shows metal drive gear 3924097 , plastic driven gear 3860346 for 1968 Camaro with E70x15, 4.88 gears and 4 speed.

[ss427copo]

I got your solution. See my eBay book collection of GM manuals. Item #184155128256
JerseyJeffVintageManuals
Jeff

[SMS]

Thanks everyone. Great info.