Author Topic: BIS, Air-cooled gearbox bellhousing shapes  (Read 347 times)

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MoonUnit

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BIS, Air-cooled gearbox bellhousing shapes
« on: May 03, 2019, 05:33:49 PM »
Hello all,

can anyone tell me if the stud / bolt hole placings (ie the mounting holes) are the same for the BIS and 126 gearbox bellhousing? I know that the starter motors are in different places, but I am wondering if, apart from that, a 126 gearbox would bolt on to a BIS engine.

Similarly, would a 500 bellhousing bolt on to a BIS engine (barring the starter motor issue)?

Thanks very much.

Gordan

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Re: BIS, Air-cooled gearbox bellhousing shapes
« Reply #1 on: May 03, 2019, 09:03:42 PM »
The aircooled gearbox does not fit directly, but if you swap the bell housing its just fine. I did it on my old bis, worked like a charm.
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MoonUnit

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Re: BIS, Air-cooled gearbox bellhousing shapes
« Reply #2 on: May 04, 2019, 10:06:22 AM »
Thanks. As I understand it, the gearboxes for the BIS, the 126 and the 500 are essentially the same shape, but the bellhousings differ. Those bellhousings can be fitted to any of the gearboxes, so provided you get the right bellhousing, you could fit any box to any car?

Thanks again.


Rusty's Uncle

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Re: BIS, Air-cooled gearbox bellhousing shapes
« Reply #3 on: May 04, 2019, 02:45:06 PM »
Thanks. As I understand it, the gearboxes for the BIS, the 126 and the 500 are essentially the same shape, but the bellhousings differ. Those bellhousings can be fitted to any of the gearboxes, so provided you get the right bellhousing, you could fit any box to any car?

Thanks again.

The 500 gearbox has no synchromesh and all 3 versions have different final drive ratios. What exactly are you trying to do?

Da Londo

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Re: BIS, Air-cooled gearbox bellhousing shapes
« Reply #4 on: May 04, 2019, 03:45:56 PM »
Bis is 4.333, aircooled is 4.875 btw

MoonUnit

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Re: BIS, Air-cooled gearbox bellhousing shapes
« Reply #5 on: May 05, 2019, 11:02:33 AM »
Thanks. As I understand it, the gearboxes for the BIS, the 126 and the 500 are essentially the same shape, but the bellhousings differ. Those bellhousings can be fitted to any of the gearboxes, so provided you get the right bellhousing, you could fit any box to any car?

Thanks again.

The 500 gearbox has no synchromesh and all 3 versions have different final drive ratios. What exactly are you trying to do?

I am researching the cost of converting a 126 to electric drive. I have found a company that sells a kit for converting a 500, but a 500 in good condition is quite expensive these days. However, the kit includes an adapter plate, which allows the electric motor to be attached to the 500's transmission by bolting on to the bellhousing.

If I know that the bellhousing of a 126 air cooled or BIS matches the bolt patterns of the 500 bellhousing, then I know I can use the kit to convert a BIS or 126 air-cooled, both of which are cheaper than a 500.

If, for example, the bellhousings can be interchanged between all three models, I can buy a BIS and a 500 bellhousing and should be good to go.

Does that make any sense?