Speedo photos to Munie speedo post

[Wayne M.]

Re: Speedo photos to Munie speedo post

OK Jack; now that the gear is off and the new one has arrived, time to do a little precision measuring. Frst, is there 8 teeth on both (ie. 8 locations around the circumference, where a tooth merges with the side) ?
Next, get out your dial or digital caliper and measure diameter and width. Width is easier (more accurate), except on that chewed-up specimen, could be a challenge.

For low numerical ratios (3.08, 3.36, 3.35, [and 3.70 if you use the silver 22-tooth gear]), #3708145; 1.765" dia, and 0.531" thick.

For 3.70 [with green 22-tooth] and 4.11's #3708144; 1.850" dia, 0.610" thk.

For 4.56 gears; # 3845079; 1.922" dia, 0.453" thk.

Let's hear what two you have.

[Jack P.]

Re: Speedo photos to Munie speedo post

OK Jack; now that the gear is off and the new one has arrived, time to do a little precision measuring. Frst, is there 8 teeth on both (ie. 8 locations around the circumference, where a tooth merges with the side) ?
Next, get out your dial or digital caliper and measure diameter and width. Width is easier (more accurate), except on that chewed-up specimen, could be a challenge.

For low numerical ratios (3.08, 3.36, 3.35, [and 3.70 if you use the silver 22-tooth gear]), #3708145; 1.765" dia, and 0.531" thick.

For 3.70 [with green 22-tooth] and 4.11's #3708144; 1.850" dia, 0.610" thk.

For 4.56 gears; # 3845079; 1.922" dia, 0.453" thk.

Let's hear what two you have.

My old gear pictured is the one with 1.76 and .53

New gear (fat one) 1.85 and .610 This gear cal below suggests the silver small 22 tooth # 3987922

http://www.stl-vettes.com/65Vette/GearCalc.htm

3987922 ===> 22 tooth 'SILVER' Small Gear

My old gear should use the silver 22 tooth

My new gear should use the 22 tooth green or small silver? I have a new 22 silver and a new 22 green. The green is much smaller than the silver dia. wise.

Is the silver 22 I got from Zip a small or large driven gear? They don't say,



Jack

[Wayne M.]

Re: Speedo photos to Munie speedo post

My old gear pictured is the one with 1.76 and .53

New gear (fat one) 1.85 and .610 This gear cal below suggests the silver small 22 tooth # 3987922

http://www.stl-vettes.com/65Vette/GearCalc.htm

3987922 ===> 22 tooth 'SILVER' Small Gear

My old gear should use the silver 22 tooth

My new gear should use the 22 tooth green or small silver? I have a new 22 silver and a new 22 green. The green is much smaller than the silver dia. wise.

Is the silver 22 I got from Zip a small or large driven gear? They don't say.

Jack -- good info. Here's a repeat pic of the two 22-tooth gears (green and silver). The silver is the smaller dia. gear (for the bigger dia. steel driven gear), which it seems you now have. So, it can be assumed that your chewed-up gear was not the original one that would have been installed in your trans with a 3.36 diff.

Your old 1.76/.53 gear should use the green gear.

[Jack P.]

Re: Speedo photos to Munie speedo post

We will know soon, I put the tranny back in on Sat. and take it for a ride, that is after I put back the headers, tail pipes, mounts shields and what ever else is on the floor.

It better work or I will scream...........

Thanks for the help. I am trying to get all the mech . work done, so I can get the car to the painter mid Feb. This tranny issue should be the last one. Please....

[Joe L.]

Re: Speedo photos to Munie speedo post

OK Jack; now that the gear is off and the new one has arrived, time to do a little precision measuring. Frst, is there 8 teeth on both (ie. 8 locations around the circumference, where a tooth merges with the side) ?
Next, get out your dial or digital caliper and measure diameter and width. Width is easier (more accurate), except on that chewed-up specimen, could be a challenge.

For low numerical ratios (3.08, 3.36, 3.35, [and 3.70 if you use the silver 22-tooth gear]), #3708145; 1.765" dia, and 0.531" thick.

For 3.70 [with green 22-tooth] and 4.11's #3708144; 1.850" dia, 0.610" thk.

For 4.56 gears; # 3845079; 1.922" dia, 0.453" thk.

Let's hear what two you have.

Wayne------


I think you have the OD's of the 3708144 and 3708145 reversed. The 3708144 is the "small" DRIVE gear that is compatible with the "large" series of DRIVEN gears (generally for 3.70-4.11 axle ratios).

The 3708145 is the "large" DRIVE gear that is compatible with the "small" DRIVEN gears (generally for 3.08-3.55 axle ratios).

[Jack P.]

Re: Speedo photos to Munie speedo post

Hi, update on Speedo gears and leak

I put the transmission in this morning, putting a tranny in a car on jack stands has to be the all time job from hell. 3 hours later, tranny in, mufflers in and all that other stuff that was in the way.

12* outside, sunny, no top, interior out for paint,

I took her out.

1 hour later, speedometer within 2 miles of gps.
3 hours later no leaks on floor

It seems that the new drive gear, plus the silver 22 , plus a good transmission man, Laurence Stiles retired, knew what to do and he did it at a very reasonable price.

It was great after so many years of not having a speedometer to work, to see it move and hold speed. Car is now all done and ready for paint in about 2 weeks.

Thanks you all for your help, hope to see some of you this summer / fall

Jack