speedo cable broke again - solution??? right speedo gear

[87coupe50]

I replaced internals of the speedo cable (lubed) and it was good for about 250 miles. This afternoon it broke again in the same place. It seems that the bend angle between the VSS and the trans mount bracket/exhaust hanger is too extreme for the cable. Is there any other adapter I can use to replace the VSS to lessen the angle? (the vss is not in use) The only other solution I can think of is to drill an angled hole through the trans mount and come up through that, but the the speedo cable will suffer from heat exposure to the exhaust.

I used the cable for the cruise control as that is what was in there already even though I don't have cruise? It's a TKO 500.

also I was told that the rear gears are 3:73. It seems that the trans has a yellow 7 tooth gear. The white 23 tooth speedo gear that was in there was reading about 10 Mph low at 60Mph. I replaced the white 23 tooth with a red 21 tooth and it is still about 3/4 Mph off. Is this the best it gets? or can I try another gear with less teeth?

 

[TRWXXA]

...also I was told that the rear gears are 3:73. It seems that the trans has a yellow 7 tooth gear. The white 23 tooth speedo gear that was in there was reading about 10 Mph low at 60Mph. I replaced the white 23 tooth with a red 21 tooth and it is still about 3/4 Mph off. Is this the best it gets? or can I try another gear with less teeth?

3/4 mph off at 60 mph is only a 1.25% error. That's pretty effing good.

Of course, your determined accuracy is only as good as the method you used to measure it. If you were pacing another vehicle, this would only mean that you are within 1.25% of that other vehicle's speedometer (which could be reading up to 10% too fast from the factory).

Depending on your tire size, the correct speedo gear (assuming you have a pre-1990 5-speed) is either a black, 20-tooth gear, or a red 21-tooth gear. They will get you close, but very rarely will you get a 0% error.

 

[87coupe50]

Thanks TRWXXA,
Isn't that more like 5 - 6.6% off?

I compaired it to my GPS which has always seemed pretty accurate. I figure if dropping 2 teeth corrected 6 Mph another tooth would correct another 3 Mph. Not trying to get it dead on but as close as possible with what is readily available. I'm currently running 275/45 17 inch and it's '87 with 5 speed. I think I'll try the black 20 tooth gear if I can find one.

I replaced the entire cable and it was a ****** trying to get the cable into the VSS. It is currently working and no bouncing this time. Will see if it holds up.