mk1-forum.net

Anybody have a view on whether the post 64 cutaway skirt on the S front really improves brake cooling in practice.
The reason I ask is I am replacing the front panel on my May build 64 S and wondering whether its worth using the later cutaway panel. The car with a 649 cam 1293 will be used for rallying. I think the changeover date was September?

Back in 1960 the 850 works cars had the front panel cut away to improve the cooling of the drum brakes. They even fitted deflectors to push the air towards the brakes. I would say, if they did it, and the factory adopted it, then it was probably worthwhile.

D

I came to a compromise and cut holes out - not sure how much difference it made tho as it still cooked the shoes on a decent road rally

That was my thoughts! Very neat work

Need bigger holes!

D

Dearg1275 wrote: ↑Mon Jan 04, 2021 10:28 pm Need bigger holes!

D

and stop left foot braking as well In the long run it did that on it's own as I put the holes too close togther and the skinny bits were easily damaged by stones. Was ondering next time I do it to use MK3 elf air intake tubes that sit under the wing and point these at the brakes

I wouldn’t think cutting away a front panel will make a hapeth of difference on a historic rally car. Stopping heat transfer through the pads might.

So Pete, how would you reduce heat transfer if someone is serious about it? I picked up a sheet of Teflon and have thought about cutting circles to place between drive flange and disc. Also perhaps Teflon shims between pistons and pads. I have the high grade disc cryogenic treated. One of my favorite Vintage Races is the Jefferson 500 a one hour enduro for small bores. A three point five mile track with 3000 ft. straight. Here where NASCAR four tire stops with fuel 12 seconds there are teams that can't make a required 5 minute stop in five. Stop requires driver to stop in pit, shut down, get out and hold fire extinguisher for fire suited fuel man. It always surprised me how many had issues on the out lap due to cold brakes. A late fall race with cool temps I found it best to drag the brakes a little down the 3000 straight on out lap before the 120 degree turn. Steve (CTR)

Pete wrote: ↑Wed Jan 06, 2021 2:17 pm I wouldn’t think cutting away a front panel will make a hapeth of difference on a historic rally car. Stopping heat transfer through the pads might.

To be honest I have no Idea how much deference it made, but I liked look of it I have to agree the speeds and distances we get upto on historic is not the same as the good ole days, so what is more effective either volume or velocity of the air to remove heat

The better improvment was the best racing material shoes I could find (drum brakes) and DOT6 brake fluid.