Author Topic: S1/S2 Front Brake Calipers. Were they 12 or 14?  (Read 264 times)

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Offline 314159td

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S1/S2 Front Brake Calipers. Were they 12 or 14?
« on: Tuesday,May 21, 2024, 08:00:12 PM »
For the longest time I assumed that my Europa had Girling type 12 calipers, as peering behind/under the wheel revealed only one clamping bolt on the bottom, like a type 12. Little did I know, there's something between the 2 bolt type 12s and the 4 bolt type 14s: three bolt type 14 (14p?) They have 48mm pistons, like a 14 would.

I went to remove the front calipers so I can bug my rebuilder, and found these. Googling the casting number got me to an FVP rebuilt caliper that's listed as fitting all Series 1 and 2 Europas (67-71). It also lists a 48mm piston, so some parts directory definitely has type 14 listed as fitting early Europas.

I'm trying to ascertain if my car left the factory like this, because it seems that it did. They looked a little tight around the dust shield (probably designed for 12 and the same part as a Mk1 or 2 Spitfire), but fit just fine. I don't see any evidence of mucking with the brakes or plumbing or etc.
The only place I've seen it mentioned that the early Europas used type 12 calipers are on forums including this one. That finally took me to the obvious solution of pulling up the parts book, which shows type 14s as being for a Series 1 (and 2) car. The pistons listed, 36J6000, are 48mm type 14 pistons.

Given all that, I'm fairly certain that not all (any?) early cars rolled out of the factory with type 12 calipers.  My concerns of overbraking the fronts by installed 14s are also likely unfounded in that case.
« Last Edit: Tuesday,May 21, 2024, 08:03:16 PM by 314159td »

Offline 314159td

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Re: S1/S2 Front Brake Calipers. Were they 12 or 14?
« Reply #1 on: Tuesday,May 21, 2024, 08:07:57 PM »
I'm also seeing 36J6000, 036J6006, and 036J6071 in various places of the parts manual as caliper pistons for the S1 and 2 cars. As those are lotus P/Ns I'm going to assume something about the piston spec changed along the way. Maybe Lotus wanted a different alloy or tolerancing, or Girling updated their spec and Lotus changed the P/N to keep old and new stock separate. Hopefully unimportant.

Offline EuropaTC

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Re: S1/S2 Front Brake Calipers. Were they 12 or 14?
« Reply #2 on: Tuesday,May 21, 2024, 10:25:48 PM »
John is the S1 expert on here, has gathered an impressive amount of data on the S1 so he's the most likely to be able to answer this one.

As for those calipers, they look the same as those fitted to my '68 Elan when I got it and replaced with the later top entry calipers early in my ownership. The '63 Elan S1s apparently had type 12 calipers and it's rumoured the first S2s also had type 12's, changing to side entry 14s before the S3 came out around '66. I was told by a local specialist that the side entry calipers weren't as rigid as the top entry, 4 bolt affairs hence I changed them rather than overhaul the originals. 

Given the first Europa was announced in late '66 making it in development around '65 and sold as a light, cheaper car to replace the 7, they could easily have been using old stock type 12 calipers. Against that, several road tests of the period mention "heavy duty brakes off the latest GT6/Vitesse" which doesn't sound right, but who really knows what went on 50-odd yrs ago ?

Offline jbcollier

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Re: S1/S2 Front Brake Calipers. Were they 12 or 14?
« Reply #3 on: Wednesday,May 22, 2024, 06:38:04 AM »
I'm not that much of an expert on S1s, especially early ones.  Serge Sleurs has chassis # 460002 and had "4-bolt" calipers on his.  Whether original or not, who can say for sure.

https://www.youtube.com/watch?v=UUJuW6Ho2LY