Lotus Elan and Lotus Elan Plus 2 Forums

Has anyone fitted a tandem master cylinder to a RHD +2?

There's a Nissan Sunny (1200) part that seems to work on the standard Elan but there's not enough space in the front of the pedal box for it, my rough measurements show about 14cm and the Nissan part is about 16cm long.

thanks
Mike

I have a +2 and my racing colleagues have told me the tandem cylinder from the Triumph Spitfire 1500 could be fitted.

Thanks, it looks ok but the big question is will it fit a +2? Has anyone here actually installed one?

I've tried looking online to find the dimensions but no success so far.

mikealdren wrote:Thanks, it looks ok but the big question is will it fit a +2? Has anyone here actually installed one?

I bought one and was unable to fit it. On my RHD car the master is too long and fouled on the corner section of the bulk head. I've seen recently a custom peddle box for a +2 (Facebook group) that angled the master this:
- gave the extra space needed
- corrected the slop of the fluid reservoir

On a LHD it would be on straight section and would likely fit.

Looking online there does seem to be multiple variants of the master. RImmerbros shows a an export version that looks shorter:
https://rimmerbros.com/Item--i-GRID005772

Not sure if its the right bore diameter thou. Which brings in a critical question servo assisted or not? If you have servos there lot of larger diameter master options around. It just the combination of tandem and small bore that is difficult.

It might be you can find a different variant on the master (supply or year/model of car) that would fit. The one I got had the large reservoir lid on it.

I have one. Its a caterham AP racing master cylinder.
Not sure if they still sell them, I have a feeling the new ones are the wrong bore size. Mine was second hand.
Fits with no bodywork modifications, no servo on my car
I did lots of research a while back, can't remember why I didn't go spitfire, but this one was bolt in although I had to connect the brake hoses before it was secured to the pedal box. I think most of my info came from this forum, although, of course some of it will only apply to LHD cars.

Another picture

Thanks both, the Caterham AP system looks good and I guess that AP still make them. Bet they're expensive!?!?

I know a Caterham engineer so I'll explore further.

Mike

If you Tandem Master cylinder what's the situation with your Insurance company. It's a big mod from original homologation/type approuval
Alan

I would say that it's a smaller mod in terms of performance than fitting the Spyder Sierra discs and calipers. It gives the car a significant safety improvement, the single circuit system would not have passed the EEC regulations in the 1970s as the handbrake would certainly not provide enough secondary braking.

Having looked again, I had measured the available space incorrectly and the Nissan M/C might fit. I'm looking to source a 2nd hand part.

The challenge with the Triumph part is that outlets are on the wrong side so the brake pipes would need routing over or under the M/C.

mikealdren wrote:I would say that it's a smaller mod in terms of performance than fitting the Spyder Sierra discs and calipers. It gives the car a significant safety improvement, the single circuit system would not have passed the EEC regulations in the 1970s as the handbrake would certainly not provide enough secondary braking.

Strange cars were imported into France by "Royale Elysée" no problem (single master cylinder).
It's not if we consider it an improvement, it's a question of "Type approuval/Homologation".
If you have a bad accident the car will be inspected and Insurance companies go by the rules.
I'm sure the car would not pass "le Mines " here in France. Part of the French MOT is also checking to see if the correct size of Tyres have been fitted.
Alan
corrected royale not champs

Compliance testing evolved in the 1970s and by the time I was brake testing cars for Vauxhall at Millbrook (about 1978, in addition to ultimate stopping performance and fade performance, cars had to meet a lesser secondary braking standard, a standard that could be met with a single failure. Vehicles with good handbrakes could sometimes meet this with single circuit brakes but dual circuit brakes and pressure limiting valves on the rear circuit were becoming common.

It seems that France and Germany in particular are becoming stricter on homologation than the UK. We can still modify cars more freely here although it's important to keep the insurance company informed.

Will the factory dual master not fit?

I think it is the same as Europa except for the reservoir, which I think is NLA

Very interesting, I didn't realise that there ever was a tandem M/C but looking at the parts list, there was in the USA. Has anyone ever fitted it to a UK car and, more importantly, are they available? I suspect they are some sort of standard Girling part.

The USA/federal cars had a large diameter master and dual servos. So the master cylinder isn't suitable unless you want to have dual servos on the car.