Author Topic: Speedometer Gear Housing - What do I need?  (Read 603 times)

Offline hladkib

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Speedometer Gear Housing - What do I need?
« on: August 29, 2023, 07:39:32 AM »
Hey All,

Long time lurker.

I'm trying to find the correct speedometer gear housing, but I have failed twice to order the incorrect part.

I have a 700r4 and want to update the drive gear to correct my speedometer. I did all the math and calculations and have found that I need a 44-tooth drive gear.  I have ordered a part from Summit, having to wait months for it to arrive only to find that the OD of the housing is incorrect. I found one on eBay it promptly arrived and that is the wrong size.

My question is: What speedometer housing do I need? My current speedometer gear housing measures 1.93" and the ones I ordered are 2.07"

Summit Part
https://www.summitracing.com/parts/TCI-880023

Ebay Part
https://www.ebay.com/itm/175116843392

Offline VileZambonie

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Re: Speedometer Gear Housing - What do I need?
« Reply #1 on: August 29, 2023, 05:55:35 PM »
Install it without the seal and see if it fits. If it does the housing is probably crusty.
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Offline MIKE S

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Re: Speedometer Gear Housing - What do I need?
« Reply #2 on: August 29, 2023, 09:48:47 PM »
2.07 is correct for a 700r4 with a mechanical speedometer. Is it possible that you are using a tail shaft housing for a 700r4 designed for an electronic speed sensor?