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Longbridge 100-6 Tach Cable and Speedo Angle Drive Questions

blueskies

Jedi Warrior
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The tachometer cable from Moss will not reach from the distributor to the tach. For the early 100-6 cars they list #021-387, which is only 2'9" long. The cable for later cars is listed as 4' long. Did the early Longbridge 100-6 cars not use a tach drive at the distributor? How did they route the cable to make the 2'9" cable reach? I have tried pretty much every possible routing, and it does not reach. Even drilling a new hole in the metal above the transmission might not help it reach.

The second question has to do with the angle drive that fits onto the overdrive unit for the speedometer cable. Is there a reason that one needs to use an angle drive? The speedo cable threads onto the fitting at the overdrive just fine. Does the angle drive change the calibration/gearing of the speedo, or is it just there to add clearance for the transmission tunnel? Is extra clearance necessary?

Thanks for any help.
 
I went and looked at Moss website. It shows the 2' 9" cable for the 100. This makes sense for a LHD 100(which is what I own) as the tach drive is on the left side of engine. If you have a LHD 100-6 with a tach drive distributor, I would suspect that you need the 4' cable. Moss info is not always correct.

The angle drive does not change calibration(it has a 1:1 ratio) and it is necessary. Without it you would be putting a sharp bend in the cable to keep it from rubbing against trans tunnel. Tach/speedo drive cables do not tolerate sharp bends.
 
Thanks. From the Moss website:

021-387CABLE, tachometer, 2"9", LHDBN1, BN2, BN4 to C.E.38837

Mine is a BN4 under that 38837 cut off. Maybe it is an error in the Moss listing.
 
The fact that they lump it in with the BN1 and BN2 is why I cant possibly think the listing would be correct for any LHD six cylinder car. It would probably be just right for a RHD six cylinder, though.
 
.... Maybe it is an error in the Moss listing.

Nah, they wouldn't make a misteak!

Mine is longer than 2'-9" and closer to 4', but I can't get an exact measurement. It comes through the firewall just to the left of the control box (when viewed from the front of the car).
 
The second question has to do with the angle drive that fits onto the overdrive unit for the speedometer cable. Is there a reason that one needs to use an angle drive?

Yes it eliminates a potentially critical bend in the cable.
 
I laid out this string to follow the path from the rear of the tach (near the spray nozzle) to the firewall, made a sharpie mark there; followed the cable from the firewall to the tach.
Total length of string: 44". Plenty of room between the heater and shroud to accommodate the additional 4" for the 48" cable.

TachCableString.JPG
 
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