Upgrade to dual circuit brakes

[Lotus 50]

My early Plus 2 has the original single circuit brakes. Is it easy/common/recommended to upgrade to the later dual circuit?

[mbell]

It's good but tricky to get a suitable dual master for rhd. For lhd You can fit a early spitfire dual master.

A few threads on here already, including one I started.

[vstibbard]

HI

Nissan had a bolt in alloy (adds lightness ) dual circuit 11/16th M/C that bolts straight in. I've used them on numerous Elans.

The only point to note, is to remember to check to see if it has a residual line pressure valve. If fitted remove it, as its designed for front disk/rear drum brakes. If you buy it from a brake shop they can help you.

The maker and part number is: Tokico JB1117 Dual Bore: 11/16 inch (17.46 mm) (with pushrod) is approx $150-200 here in Australia. You want to get the old Datsun (Nissan) 1200 Version as it has the vertical bolt pattern.

It may also be know as Nissan F10. HEre's a llink to an article of one being fitted to a Lotus Europa.

http://www.lotus-europa.com/manuals/mis ... f10_mc.htm

Note, the same part number is used still on newwer Nissans but they have a horizontal bolt pattern

Other manufacturers produce them so search for Nissan JB1117 dual M/C

Cheers

Vaughan

[mikealdren]

Reading earlier posts on here has finally convinced me that neither the Spitfire nor the Nissan solution works with RHD +2s although they will fit the Elan with remote reservoirs.
The Spitfire part is apparently too long and fouls the inner wing (although you could probably modify this to provide more space). The Nissan part has outputs from the bottom of the M/C and there isn't enough clearance for these although you may manage with banjo bolts on the output.

Has anyone here done either (or anything else)?

[mbell]

Mike is correct about both masters mentioned.

My in-depth thread on this topic:
viewtopic.php?f=42&t=38002

I am still running single circuit. I think I've seen pictures of a shorter spitfire master that might fit but not found vibrate info on it. Also thought about doing an adapter so the master could be mounted at an angle which would allow the spitfire one to fit.

[vstibbard]

Apologies it has bleed ports on right side and bottom outlet ports, the bottom is steel and would take banjo and copper/aluminium washers.
Cheers
Vaughan

[mikealdren]

We must be talking about different Nissan M/Cs, the ones discussed on the thread MBell refers to are underneath but if there is a side entry model and on the correct side of course, that would be very useful. I need to look further. The only ones I have found recently have had too large a bore, usually 13/16" or 15/16"

[vstibbard]

Datsun 1000 coupe JB1117 also fitted to Mitsu Lancer (old RWD ones) One or 2 odd Mazda as well.
Most if not all of those are vertical mount though Datsun/Nissan 1000/1200 coupes from memory etc had vertical mounting holes dual master cylinder 11/16 bore side entry under the part number JB1117 which I checked as I’ve still got the box from the last one I fitted.
The jb1181 is a 3/4 version.


I’ve used them on numerous Elans with integral reservoirs and also using the Tilton remote set up.

[mikealdren]

Many thanks for this. They seem to be readily available in Australia but I haven't been able to find them in the UK but I'll continue searching - postage to the UK makes them rather expensive.

[mbell]

Do the JB1117 matter also have protusions underneath?

My memory was they did and that they would foul the peddle box on a +2.

[vstibbard]

They do, the other option I’ve found ages ago was an 11/16 dual that I understand was off a bed for van, it requires remote reservoirs, no protrusions underneath. I’ll have a look to see if I’ve a picture of it and details of part number in my old book.
What about the caterham dual master cylinder?
Cheers
Vaughan

[pptom]

See my post here:
viewtopic.php?f=31&t=46881&p=338036#p338036

AP/ Caterham master cylinder

[mbell]

Looking at spitfire masters again, there appears to be two different dual circuit masters

64068680 1967-75 "big cap"
74066020 1976-80 "small cap"

I bought and tested 74066020 that was too long to fit. 64068680 looks like it is shorter and might fit. The reservoir isn't ideal as designed to be mounted an angle but probably ok or should be able to find a solution.

I think the caterham would be great but I've never found one for sale or they were very expensive!

[pptom]

They do come up for sale second hand occasionally.
https://www.ebay.co.uk/itm/Lucas-Girlin ... 635-2958-0

I think I just had one on my eBay saved list for a couple of months. Up until I got it I was in the same boat as you, pilling my hair out wandering how to solve the problem.

[Lotus 50]

The federalized Plus 2 would have had dual circuits. Are those parts available and desirable?