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Indy brake pedal ratio
Echidna - 18/12/08 at 11:06 PM

Hi! Could anyone give me the brake pedal ratio of the stock MK Indy brake pedal? Any pictures will be appreciated too! Thanks!

Mark G - 18/12/08 at 11:22 PM

Don't know about the ratio but I've attacted a couple of photos for you



mackei23b - 19/12/08 at 08:14 AM

Here are some pics of mine





Cheers

Ian

[Edited on 19/12/08 by mackei23b]

nick205 - 19/12/08 at 12:41 PM

You can set the ratio (to some extent) by drilling the clevis hole where you want it (within reason).

02GF74 - 19/12/08 at 02:15 PM

quote:
Originally posted by chris mason
The pedal ratio is somewhere around 3:1

you'd be better off trying for a different set up if possible, and try to get nearer to 5.5:1

Chris



yeah - that struck me too 3:1 is a bit low.

5:1 is what you should aim for; most of the the pedal boxes are lke this.

Echidna - 19/12/08 at 04:59 PM

I know that 3:1 is quite low! In my own setup for my Haynes Roadster i made it around 5.7:1.

Then, in the case of the MK Indy if you drill the clevis hole lower to increase the pedal ratio, the angle of the clevis will be greater, because the MC is fitter quite high on the backplate.
In my case i fitted my MC as low as possible to achieve the lowest angle between clevis and MC axis possible.
If you drill the clevis hole lower on an MK pedal, i think that the greater angle between MC axis and clevis will give problems to the MC reliability. What do you think?

[Edited on 19/12/08 by Echidna]

Echidna - 19/12/08 at 05:05 PM

To understand what i mean: Rescued attachment Indy Brake Pedal fitted 2.JPG
Rescued attachment Indy Brake Pedal fitted 2.JPG

Echidna - 24/12/08 at 05:43 PM

Anyone?

Bluemoon - 27/12/08 at 06:05 PM

Did something similar to you photo, but not as high an angle (low pivot point). Had to make my push rod conical at the end to stop binding with the end of the cylinder (use an HT M8 bolt, ground end to around M6 size).. This is all before SVA and it's not been on the road..

I think making an angle plate to tip the master cylinder up a but might help (not done this).

U2U if you want more info.

Dan

[Edited on 27/12/08 by Bluemoon]

Echidna - 27/12/08 at 06:22 PM

I think i got an idea... Rescued attachment Indy Brake Pedal fitted 2.JPG
Rescued attachment Indy Brake Pedal fitted 2.JPG

Bluemoon - 28/12/08 at 12:15 PM

I'd not recommend that, there is a lot of pressure on the rod in an emergency! Last thing you want is the rod bending at the new bend... Then no brakes...

Your idea is sound apart from that.. If you engineer a sufficiently strong push rod design it would be o.k. but it would be simpler to move the master cylinder down a bit, or angle it..

Dan

RobH - 30/12/08 at 10:38 AM

Hi All

This subject has been talked about a lot before.

I thought this link might be of interest

Linky

Rob