Dual master cylinder

[builder618]

Years ago I saw a post about a volvo duel master cyl. repacing the single in a Elan S2 for safety. I intend to run with no emergency brake ( not that it ever worked anyway) , but in the 40 years since I last ran the car, I have gotten old and conservative-- or just old, so the redundency would be nice. i don't care about originality, after 40 years of ownership, I do what I want. I am sure a balance valve if needed is an easy adj. So do we have a source or at least a model # for said master.

Thanks

[UAB807F]

Hi,
There have been quite a few threads in the last year or so about dual circuit brakes and folks have used different sources of master cylinders. This is one thread with lots of current info for example;

http://www.lotuselan.net/forums/elan-f14/tandem-master-cylinder-t19064.html

but you can find plenty more by searching for "tandem master cylinder", etc. There's also a debate over bore sizes, "to servo or not ?" and whether or not you keep to standard front calipers or use the larger 16P ones from the +2, etc. Personally I went for a 0.7" bore from the later Triumph Spitfire, etc, but with a remote reservoir mounted on the inner wing by the airbox. Lots of choice with the kit car suppliers (caterham, westfield, etc) or classicar automotive if you're in the UK.

Brian

[Galwaylotus]

I did pretty much the same thing - 0.7 inch bore, remote reservoir on the wing - but I bought a new AP Racing tandem m/c as used (I believe) on Caterhams. Eliminated the servo and installed GreenStuff pads on the front with steel braided Aeroquip hoses on all corners. Very satisfied with the result.

[builder618]

Thanks for the info, the .7" bore size seems to be the controlling factor. I am doing a frame up so everthing will be new. Being that we drive on the correct side of the road in Fla. USA the remote res. should not be needed. Intend to reinforce mounting area with large plate to contol flex at master mount.

Thanks guys, open for anymore comment available.

[Jeff@Jae]

Finding a dual circuit .7" brake master cylinder seems pretty easy but finding one with ports on the correct side for a LHD Elan seems pretty tough. How is everyone dealing with the plumbing of the available master cylinders with the left hand outlet ports ?
I wouldn't call the handbrakes an emergency brake but as a parking brake they do the job well. If they don't work well after adjustment seems to to either result in brake drag or not working at all the culprit is usually the missing little spacers in the operating arm. For some reason the little bolts in the fork of the rods connecting the bellcrank to the calipers is smaller than the hole in the operating arm. Without that spacer adjustment is hopeless.

[gerrym]

Jeff, I posted some years ago details of installation of the Spitfire 1500 tandem master cylinder. Hydraulic connections are on the right hand side of the master cylinder (that true right looking forward to nose of car from drivers seat with the master cylinder as installed in the Lotus). Remote needed and no big deal.

Regards
Gerry

[carsmutley]

i know this is an old topic, just wondering if anyone has pics of a Spitfire tandem master using a remote reservoir ? cheers

[UAB807F]

i know this is an old topic, just wondering if anyone has pics of a Spitfire tandem master using a remote reservoir ? cheers

here ya go.....

elan-dual-circuit-brakes002a.jpg (79.35 KiB) Viewed 894 times

and with the remote mounted on the inner wing

elan-dual-circuit-brakes004a.jpg (75.93 KiB) Viewed 894 times

reservoir was (i think) from a landrover with the low fluid warning switch incorporated. It's wired into the handbrake light because I didn't want to add any more warning lights. The bracket is home made from aluminium sheet.

Brian