Speedometer gear

[James Bell]

Is anyone familiar with speedometer gears, the plastic gear that fits into the side of the transmission? My stock one was destroyed, I purchased an used one - 17 teeth on the gear, and my speedomoter now reads about 5% slower than my true speed. For exxample, an indicated 60 mph is actully closer to 65 mph, (as tested by a second hand on watch against a some measured miles). Any suggestions on whether I need to install a gear with fewer teeth or more teeth? I can't remember if I have a 3.36 or a 3.54 rear axle and tires are not stock - 205/60/14, so calculating from rear a axle ratio or tire size won't help.

Thanks

Jim Bell

[5thhorsemann]

More teeth = lower reading (less input RPM) try a 16 tooth gear (white gear)

[Zed Head]

Do you still have the old one? You should be able to count what's left of the teeth. Fewer teeth will speed up the speedometer. 16 is the smallest change you could make to the next level.

Here's a link to study, go down the page about half way to see the options and colors - http://www.geocities.com/inlinestroker/ratio.html

Looks like you might have a 3.36 and you installed a 3.54 gear.

Edit (slow writer) - looks like agreement on 16, color undecided...

[SteveJ]

According to this page, 16 is yellow.

This site may help with picking the right cog.

[Bruce Palmer]

See Jim, I told you the info would be rattling around in the hallowed halls of Classic Z cars dot com. We will proceed accordingly, diggin' and a scroungin', diggin' and a scroungin'.

[5thhorsemann]

According to this page, 16 is yellow.

This site may help with picking the right cog.

Ivory?