mk1 rear disc conversion

[roccodingo]

Simon, I would just buy new ones mate as used ones tend to be full of crud from brake fluid not being changed regularly enough. I can sell you a couple used ones but frankly there really bin material when it comes to braking safety.

Classic Parts Center

folow this input :-Sie sind hier: / Scirocco / Corrado / Scirocco II / Fahrwerk / Bremsen

124.66 Euro each..

[cartertronic]

Thanks mate, I'm thinking I'll source new or aftermarket adjustables...

Looking at aftermarket adjustables from Wilwood and other brands, none seem to be adjustable to reduce brake pressure by anything more than 57% - Brake Proportioning Valves - SummitRacing.com

Apparently this won't be enough as per this thread on vortex: VWVortex.com - Wilwood Porportioning Valve Question

So looks like OEM is the only way to go.. surely this can't be right, what about racing applications!?

[Peter Jones]

They're also still available from Lotus.

[cartertronic]

Awesome, thanks Pete.

Managed to find them for sale for $105.48 USD each x 2 = $250AUD incl. postage

https://www.busdepot.com/brakes/533612151a

Order placed...

EDIT: Gutted, got an email back from them saying the part is obsolete .. i.e. from Classic Parts Center only

[hiho]

VW Golf GTI G60 VR6 Turbo Druckminderer Bremsdruckregler 3/15 | eBay

I think they're ATE part no. 24.6043-1701.3 (a Pug part with the same characteristics) however adapters are required to mate it up to the VW brake lines

[Shadow_Rusty]

Hmmm, not too sure how useful this is to us, but the Lotus guys have been rebuilding 3/35 units to be 3/15 units by changing the spring.
Lotus Elan Central • View topic - GM Proportioning Valves investigation for compatibility

Has anyone checked the spring in a 3/15 unit and compared it to a 3/35 spring?

[roccodingo]

yes, and the only difference is the spring. Looked at getting one of the local spring makers to do me a run of springs for this about 6 years ago, cant find the damned quote...

make sure you clean all the old brake fluid, rust and gunk out and assemble with new o rings.

[Shadow_Rusty]

As my wheel fell off last week due to a failed drum bearing, I'm re-looking into my disc conversion...
I have everything I need, except for the rare as 3/15 prop valves...

However, after speaking with one of my friends who works in a brake shop, he suggested that I just cut off one coil from the spring inside a 3/35 unit, which will lower the '35' part of it.
They had to do it to a car (not a golf) earlier in the week as the rears were locking first, and the technique worked well.

So, keeping that suggestion for a last resort, I then spent several hours trying to find the spring dimensions that Rocco mentioned above, but to no avail.
I did however, stumble accross this post on a Lotus Forum

To progress this to a conclusion I need to know how many people would be interested
I have the spring spec to convert a Vauxhall valve at 3/what ever to 3/15 so I can get the springs made
Spring rate 4.58 N/mm
33mm long
14.1 od
10.9 id
16 gauge wire diameter
7 coils ground ends

I have a wholesale supplier that may be willing to sell his stock all be it limited of Vauxhall valves so that may give us 50 or so
I can get the end that allows the valve to be fitted in the fixed pipe work made to eliminate the problem with stripped threads
Cost at a calculated guess about £35.00 each for a complete replacement unit.

Bob

Indeed, that whole thread is very interesting as the elan uses a similar setup to our Mk1's.
Also, this post from the same site explains the system, and how it works, very well.

So, now the questions are,
Has anyone got a damaged 3/15 they can check the spring size?
Have you stumbled upon the 'correct spring' elsewhere, and are being 'selfish' and not 'sharing'? (lol)
Does anyone have some 3/35 valves fitted that they have modified?
etc.

[sports racer]

Would an adjustable line locker work the same? I've got one that is for preventing the brake fluid building pressure to the rear brakes so you can have the front brakes on (using the brake pedal) and do stationary burnouts on your rear wheel drive car.

Because I can adjust the amount of brake fluid going through the line locker I should be able to change how well the rear brakes work with a flick of the hand.

[roccodingo]

Heritage are selling a non oem equivalent.... still pricey tho..

https://www.vwheritage.com/shop/scir...umbStartRow=33

My last set of genuines were 104 Euro each....

[Notso Swift]

Sports Racer
It isn't a line locker, that is a completely different thing, it is a proportioning valve, and you can get adjustable ones.
They work on a variable pressure increase then they cap and the pressure increase changes (ie lower) and they are a lot cheaper than the Heritage ones, cheapies like wilwood are about $80

It would work
The he only thing is with a diagonal split system you would need two and to balance them, front rear split system is easy, only one, which is what most race cars run (unless they have a $10,000 Bosch Motorsport unit, like a GT3 runs)