The 'E' Type Forum

Hi all
Does anyone know what caliper/discs are allowed for Appendix K class racing. In the back of my mind is a dim light illuminating a sign showing Mk9 front calipers and carriers, the lights not bright enough to track down and purchase a set hence the question.

TIA
Pat

try Dennis Welch motor sport for remanufactured Mk9 callipers. best to be sat down when reaching the price section.

There is a pair of MK 9 front caliper carriers on e bay at the moment for £500!
However, that is just the start. Unless you can find adaptors you will need the LWE uprights as well, not at home at moment so can't quote you the XR part numbers.
MK 9 are steel piston assemblies so will need the alloy ones with hard anodised bores. The modern re pro's are not the same as original as the piston seal is in the bore not on the piston which allows for a modern metal backed pad.
The original LWE pistons are/where bespoke with large pad backing shoes as far as I have researched as I have a few sets of them and is what I Have fitted.
There are varying types / quality / engineering solutions, some not so well thought out, just remember the physics of heat rejection and transfer!!
RS panels supply quality sets of all the above and have done for years, they will be competitively priced you should try there and do a deal before DW in my experience.
They all seem to be 2 1/8" which was std LWE, works were bigger.

Thank you oth for informative replies.

my Series 1 semi-lightweight has MK9 calipers and 12“ discs on the front. Take a look at FIA homologation sheet number 100, as you‘ll find what is allowed in there.

They were first used on the works long nose D-Types as the pads are like moderns and were far quicker to change during Le Mans type endurance events than the 6 pucks of the standard caliper.

This all suits me, as even expensive Mk IX brakes are far cheaper than the correct 6 pots used on all other Ds. I bought a pair of caliper bodies today actually, and David Manners has the 12.125" discs on offer at 75 quid plus VAT. That is the cheapest I've found by a long chalk. I intend using the DW adapter bars to fix the Mk IX calipers to Series 1 uprights.

Pete

Morning Pete,
You are spot on re the origin of the large caliper single pad on works Long Nose D's, not a lot of people know that .
However, despite the FIA seemingly allowing the 12 1/8 inche discs they are not correct for a LWE. When these larger discs are used you can't use the LWE/Long Nose D pad retaining bridge piece as it fouls the inside of the rim on 15" wheels, you might be ok with 16's. You also can't use the quick release pip pin as original, smaller short bolt is needed. An original MK 9 caliper body might need machining to provide additional clearance for the 12" disc. The aftermarket body's from the key suppliers have the mounting lugs lengthened and redrilled to step them further from the upright to allow the larger disc. Somewhat proves the point that the correct LWE disc is smaller in diameter!
Cheating comes in all forms, the fact that the MK 9 body looks stock perpetuates the myth that the disc where 12".
Regards,
Michael

here is what is mounted on my Series 1. The calipers can be bought new at Denis Welsh.

Factory upgraded brakes:


Reinforced brake hoses:

Dawnpatrol wrote: ↑

Sat Nov 17, 2018 9:51 am

However, despite the FIA seemingly allowing the 12 1/8 inche discs they are not correct for a LWE. When these larger discs are used you can't use the LWE/Long Nose D pad retaining bridge piece as it fouls the inside of the rim on 15" wheels, you might be ok with 16's. You also can't use the quick release pip pin as original, smaller short bolt is needed. An original MK 9 caliper body might need machining to provide additional clearance for the 12" disc. The aftermarket body's from the key suppliers have the mounting lugs lengthened and redrilled to step them further from the upright to allow the larger disc. Somewhat proves the point that the correct LWE disc is smaller in diameter!
Cheating comes in all forms, the fact that the MK 9 body looks stock perpetuates the myth that the disc where 12".
Regards,
Michael

Thanks Michael. Clearance should all be fine under a 16" correct peg-drive pressed alloy Dunlop (not the thickly-ribbed cast alloy 15s or even same style 16s)

Will work something out on QR pin, but am not entering Le Mans or Spa, so time is not of the essence :-) I'm sure I'll come up with something. If not, then even a stock part will do.


Who makes them except DWM? I can get new standard for $150US and use the DW adaptor brackets. Do you happen to know if the round MkIX adapters can be sawn in half and the rear half fit the caliper to the S1 upright spacing? Agree on paddock gamesmanship, but for me the giveaway would be six hole discs rather than 5, no?

Hi Peter,
RS Panels do both disc sizes and yes with 6 holes for the peg drive hubs.
I've not had an original MK 9 Disc in my hand to measure thickness. But the fact that the original LWE 11.25 disc has a XR part number prefix means it is made from a stock part, not always from the finished stock part if you know what I mean, the blank disc could be just drilled to a pattern that suits the peg drive hubs instead of 5 holes for the splined hub or steel wheel hub, also machined down on the diameter, it then gets the XR number, same with the rear discs. You could redrill the front MK 9 disc yourself?
I'm not sure what you mean wrt to round MK 9 adaptor bracket being cut in half?
The issues are, as far as I can tell are;
Is the DWM remanufactured MK 9 calliper body absolutely the same as original wrt off set and other critical dimensions? If so then their adaptor should compensate for those that think the 12" disc is correct. Also then, the item would be suitable for a Full LWE set up with the uprights and steering arms, but would not allow the 12" disc.
It would however, allow the STD spec MK9 calliper to fit to the STD series 1 upright possibly with the clearance issues I mentioned with 15" wheels. Should also mention the outer piston body would need to be heavily dressed back on the shoulder as well.
Unless DWM do two adaptors;
One for the big calliper to the std series 1 upright.
Plus one for the big calliper to LWE upright to allow the larger disc.
Then the remanufactured body would have to have two versions, std and large offset.
Hence my statement that the homologated brakes are not 12” discs, otherwise you cannot use the STD MK9 body.

Regards,
Michael

I assume you have seen the latest addition to this thread: http://forum.etypeuk.com/viewtopic.php?p=108898#p108898

NOS LWE Brake discs with Jaguar part number:


LWE Calipers:

Hi David,
Yes I did thanks. The discs look correct but that is a Dunlop pt number, the Jaguar XR number should be stamped on the edge of the disc if they are original.
The callipers are unusual, I have pictures somewhere of those fitted to PS1175 before Adrian Neweys ownership and always wondered what they are off. They look to be a much more recent 3 pot design and therefore not homologated, probably why they where removed.
The uprights also listed are interesting having the lower front lugs cut off?