9 replies to this topic

[The-Womble]

Just a quickie:

Can the auxiliary clocks from an MGB GT (voltmeter, clock, oil pressure etc.) be used in the auxiliary holes in a standard Mini wooden dashboard?

Also, what size are the standard Smiths aux. dials, just for reference?

Chris

[Big_Adam]

To a degree yes. I think some rev counter and the wiring will give you trouble. If it's a purly mech gauge (oil pressure for example) then it's just a case of finding a pipe to fit it.

Althought, good Dr. Lawson is more knowledgeable on the matter.

[mwalsh]

Standard small gauges are 52mm.

[dklawson]

MGBs covered a lot of years. The answer to your question is "maybe".

Most of the small round gauges will be 52mm as Mike said. That will be the same as a classic Mini's center binnacle gauges. The electric gauges can be made to work but you have to pay attention to the age of the MGB.

MGB through about 1964 used a mechanical tachometer. No good on a Mini.
Also Through 1966 or so they used Jaeger gauges. (Just Smiths in drag). HOWEVER, like the Minis of that period, those early gauges operated without the voltage stabilizer. Don't try using these on a Mini later than 1964 or you'll have to get all the early sending units to match.
As the MGB moved into the 1970s they switched to an electric, rectangular oil pressure gauge. Avoid it at all costs. They can be made to work but the sending units are unique and horribly expensive.
When they switched to the rectangular oil pressure gauge I think they also made the tach and speedometer smaller. Just keep that in mind.
The early electric tachs (post 1966?) were Smiths RVC type. They will not work with electronic ignitions.
The later tachs were RVI type and work with most ignition systems but they are not as stylish.
The mechanical speedos had several different ratios (Turns per mile). Some of the early ones up through the early 1970s will be calibrated for 1280 TPM (the number will be on the gauge face somewhere). The 1280 TPM speedos are very suitable for Minis running 10" tires and a 3.44 final drive. Later MGBs switched to a generic calibration of 1000 TPM which is common to aftermarket gauges but not any Mini I know of.

Well there's a lot more info than you wanted. If you go with the MGB gauges, get the MGB sending units to match. It will save you a lot of headaches. However, the fuel gauge senders MAY have identical calibrations. I don't know for sure. Don't count on the temperature senders being the same.

[The-Womble]

Ok, cool. Thanks for the info. The MGB in question is from 1975. The picture of the interior is only pretty small but you can clearly see small round gauges to the right of the Tachometer:
PICTURE

I'll bear that all in mind, cheers.

[Dan]

MGB through about 1964 used a mechanical tachometer. No good on a Mini.

Mini Spares do make a mechanical tacho drive kit that fits into the timing cover. I've never tried to fit one but it can't be hard to do, the parts in the kit I've seen look well thought out.

[The-Womble]

I'm alright for a tacho was only after the auxiliary gauges like oil pressure and things

[dklawson]

Mini Spares do make a mechanical tacho drive kit that fits into the timing cover. I've never tried to fit one but it can't be hard to do, the parts in the kit I've seen look well thought out.

I wasn't even going to mention that! I had heard the parts were available but didn't want to suggest removing and modifying the timing cover.

I'm not sure what the ratio for the MGB mechanical tachs are. On my Triumphs the tachs have typically been 3.55:1 so you can't hook those directly to the cam. (On the Triumphs the cable driven tachs are driven by a drive gear on the side of the dizzy housing). It's been way too many years for me to remember how and where the cable tach connected on the early MGBs. Perhaps they were cam driven.

[Dan]

Guessing that it's the same setup as the MGA it uses a spur gear but I can't remember how it meshes with the cam. I seem to remember that it's the same gear that turns the dizzy so I'm guessing it's 1:1. Triumphs use the oil pump spur gear don't they?

Anyhow none of this is really relevant but it's interesting nonetheless.

[dklawson]

Triumphs use the oil pump spur gear don't they?

Anyhow none of this is really relevant but it's interesting nonetheless.

The mechanical Triumph tachs I'm familiar with are all driven by a gear on the side of the dizzy housing. Now... indirectly that IS the oil pump drive... but only because the oil pump is directly below and inline with the dizzy shaft so they are both driven off the cam by the same gear.

Keep in mind that those early cable driven MGB tachs will be marked Jaeger, not Smiths. They are very nice looking period instruments but just a little different from Smiths gauges. The very first gauge I ever opened up was a Jaeger tachometer for an MGB.

This may not be interesting to everyone, but it certainly is for me.