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inboard discs
kango - 18/12/06 at 07:38 PM

SEARCHED but did not find any thing.
Has anybody modified the Sierra rear end set up to inboard discs?
This could reduce the unsprung weight at the wheels and make for easier brake lines. (no flexi pipes)
The uprights can also be designed lighter as they will not have to teke the BRAKE force only the acceleration force.
Will be a mission to bleed, but that is only once, when the car is built.


erwe - 18/12/06 at 08:00 PM

I did it with bike brakes
www.seven-nl.tk (rear section)



Ivan - 18/12/06 at 08:08 PM

Although the advantages that you mentioned are real there are several disadvantages also - the main ones of which are cooling and hastle to do safetly.

I think it would be easier and possibly cheaper in the design stage to find unsprung weight savings by simpler means such as lightweight calipers, optimum disc selection (you can go smaller with proper cooling ducts and/or possibly use motorcycle discs and calipers at the back (handbrake problem?)) , lightweight wheels and tyre selection.

A chat with the tyre producers technical advisors highlighted the fact that there is a variance of as much as 2 kg per tyre between different manufacturers of similar types of road tyres - something I had never even thought of before.

I see "erwe" has just beaten me to it - maybe I'm wrong about hastle to do


Ivan - 18/12/06 at 08:15 PM

Thinking about the bleeding - in my Cobra that has inboard discs I put a hatch in the rear bulkhead that gives easy access to the brakes from the cockpit so bleeding no problem.

Anyway I found that you have to bleed the brakes more regularly on a car that isn't used as often as your commuter just to renew the fluid because it doesn't get hot as often.

Ewe - how did you handle the handbrake?


erwe - 18/12/06 at 08:17 PM

Main reason to use these disks and calipers was that I have them on my first car (which is road legal now). Very light and very good braking. Because this setup doen't fit in my 13"wheel I did it this way.
I did a few races with this car and didn't had any difficulties or overheating yet.

And I always like to thing the hard way


JoelP - 18/12/06 at 08:34 PM

i believe you need to make sure your diff has good oil seals, as oil on the discs wont help at all. I love the idea myself, just wish i was handy enough to do it!


erwe - 18/12/06 at 08:38 PM

quote:
Originally posted by Ivan
Ewe - how did you handle the handbrake?


On this blue car there is none..
On my first seven I used a wilwood master cilinder in the rear brake line, simple but it works.
Not SVA I believe....


ed_crouch - 18/12/06 at 09:48 PM

My TVR 390SE has inboard rear discs, it uses the Jaguar XJS system.

Its actually really good, but they got a bad reputation because theyre a right bugger to work on, and hence people didnt bother to maintain them. Any system will stop working if its not maintained.

The only difficulty is that you have to disassemble the rear suspension to get the discs off: this takes about 25 hours for both sides on a Tiv, but then i did take the time to fully recon the whole lot.

Ed.


Richard Quinn - 18/12/06 at 10:34 PM

Sorry, bit of a hijack here:
Anyone in the UK successfully SVA'd with bike brakes? We use them all the time on the grassers and it got me thinking...


James - 19/12/06 at 12:35 AM

quote:
Originally posted by erwe
I did it with bike brakes



That looks extremely cool! Wish I had the skills/tools to produce that!

Cheers,
James


kango - 20/12/06 at 03:22 AM

Thanks
So I take it that this idea gets the thumbs up.
How about some more detailed photos of the mounting brackts.

What is best, mounting to the GB or the chassis