Author Topic: GT6 uprights and 'standard' hubs.  (Read 1961 times)

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Offline StephenH

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GT6 uprights and 'standard' hubs.
« on: Saturday,January 25, 2014, 01:46:34 AM »
Hmmm.... best laid plans.

Finally back home for long enough to fit my Europa Engineering vented disc upgrade.
Small problem, not enough diligence on my part before ordering parts from the UK.
Turns out my Europa has GT6 uprights and stub axles, therefore different bearing sizes.
Larger ID both ends, larger OD outer and smaller OD inner.

Doh!

Before I get to carried away with the lathe and start carving up the nice new hubs so that I can make the bearings fit, anyone else blazed a similar trail before?
I'm currently digging around the various online bearing resources to see what I can get, maybe there is a 'simple' answer (I can hope).
Also noticed the online SKF catalog has an error, the standard Europa listing is for GT6 sized bearings, not Herald/Spitfire as they should be.

I better measure the rear axles before I get too excited with the bearings and disc conversion that end as well.......
Stephen
54/1690 1969 S2

Offline EuropaTC

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Re: GT6 uprights and 'standard' hubs.
« Reply #1 on: Saturday,January 25, 2014, 09:12:51 AM »
I'm assuming the new kit comes with alloy hubs set for the smaller Europa/Herald/Spitfire bearings ?

Now this is a pure guess, but can you simply replace the stub axle on the upright with one from a Herald/Spitfire and get away with it ?  I admit I don't know for sure but I'd guess that the vertical upright was the same casting for all the range, and to fit larger bearings they just added a larger stub axle ?

If not, then rather than mess up some nice new hubs you could machine the stub axles to suit ?
 

Offline StephenH

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Re: GT6 uprights and 'standard' hubs.
« Reply #2 on: Saturday,January 25, 2014, 11:36:36 PM »
I'm assuming the new kit comes with alloy hubs set for the smaller Europa/Herald/Spitfire bearings ?

Correct, I ordered as standard size as I neglected to confirm the axle size and couldn't find any reference to upgrade in the previous owners notes and receipts.
That will teach me to make assumptions when ordering parts :-[

SKF don't list any bearing sets that will magically make my day, the Japanese companies make some weird bearing sizes so I will delve around the web resources a little more before I give up on that front.

I am sure I could fit the smaller axles but that seems a backwards step so if any machining takes place it is on the hubs.
The outer bearing isn't a big drama, bore out the hub and should be fine.
The inner bearing is smaller OD (by about 20 thou) so what I will probably have to do is bore out the hub a little and shrink a sleeve over the bearing.

Tomorrow I will be pulling the rear stub axles for the first time, wish me luck :help:
Stephen
54/1690 1969 S2

Offline EuropaTC

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Re: GT6 uprights and 'standard' hubs.
« Reply #3 on: Sunday,January 26, 2014, 03:21:19 AM »
Another random thought.

I changed the calipers on my Elan to the larger GT6 ones and now remember that I had to buy caliper mounting brackets as well. It might be worth checking that your new calipers will fit on your existing mounting brackets just in case the PO also changed those as well. The mounting brackets themselves have the same 4 bolts to fit to the upright but there is about 1/4" difference in the caliper part.  I think it was 3.25" to 3.5" on the type 16 calipers so worth checking before you start on a irreversible mod to the new hubs. 

Offline StephenH

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Re: GT6 uprights and 'standard' hubs.
« Reply #4 on: Monday,January 27, 2014, 12:39:43 AM »
The kit from Europa Engineering (Banks) includes new calipers and mounts to go with the slightly larger diameter ventilated discs.

Leaving the original discs (well they are off a Cortina GT, so not quite standard) for the moment while I decide what to do.
Machining the hubs seems feasible, although I could also have a new set made from billet, it's only metal and money :)

Meantime the rear disc conversion is proceeding, slowly.
A bit hot here at the moment and looks like the next week will be more of the same.
Not so good in the shed with thin walls and no insulation in the roof.
Stephen
54/1690 1969 S2

Offline LotusJoe

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Re: GT6 uprights and 'standard' hubs.
« Reply #5 on: Monday,January 27, 2014, 11:58:08 AM »
Seems to me the best bet is to switch back to Spitfire uprights and spindles. Have you checked with Richard? He may have already faced this issue and has a solution.  :confused:
Joe Irwin
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(The Classic Barn Find)


Offline StephenH

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Re: GT6 uprights and 'standard' hubs.
« Reply #6 on: Tuesday,January 28, 2014, 03:04:09 AM »
Have spoken with Richard and he has offered a few suggestions.
Helpful as seems is his normal way.

Return the hubs and he will machine up some dedicated replacements.
Machine the hubs I have to suit the bearings.
Machine the stub axles.
Replace the stub axles.

I'm thinking about it for the moment, no need to rush.
Stephen
54/1690 1969 S2