Adapting a Ford Festiva master cylinder to a S2 – Part 1 - Fabrication

[Grumblebuns]

I came across the Ford Festiva master cylinder as a promising candidate for a replacement S2 master cylinder and decided to see how I could make it work for the S2. The main requirement for my conversion was not to make the conversion permanent but to allow reverting back to the stock S2 master cylinder if I later changed my mind. This is what I came up with.

The master cylinder is from a 1988 thru 1993 Ford Festiva (Pic 1):
-non stepped, 0.75” tandem bore
-dual ports on right hand side, M10 x 1.0 metric fittings
-integral plastic reservoir w/low fluid level sensor
-mounting lugs oriented horizontally (east/west)

The most obvious issue was adapting the horizontal orientation of the mounting lug holes of the Festiva MC to the stock vertical mounting system. My solution was to design an intermediate mounting flange welded to the stock MC extension box (Pic 2 & 3).

There is also an issue with moderate interference between the Festiva MC flange and the original mounting bolts of the extension box (Pic 4 ). There are two options to overcome this problem. The first is to  ground out a couple of notches on top and bottom edge of the MC to clear the bolts (Pic 5). I chose this option. In retrospect, I should have cut out the bolts and drill and tap the stock holes for a 5/16” NF stud. This second option would have made for a cleaner installation and still allow using the stock MC if wanted to go back.


The second issue is the pushrod system used by the Festiva,  It's a straight rod fitting about an inch into the center of the primary piston (Pic 6&7). The Europa does not have a  pedal stop to prevent the pushrod from pulling out of the primary piston. The solution used is identical to the Courier MC conversion, a washer between the extension box and the frame (Pic .

New brake lines will have to be run from the Festiva master cylinder to the two three way junctions on the front bulkhead. Metric fittings, M10 x 1.0 on the master cylinder and 3/8” x 24 for the junctions.

The swap out and road test of the Festiva MC on 65/2501 will be performed in a couple of months. I just replaced the unknown installed front pads for EBC Green Stuff pads as reference pads for testing the stock versus the Festiva MC. I need to get some experience of stock MC with the EBC pads. My gut feeling is that the Festiva MC will perform identically to the Courier MC. I'll post a follow up evaluation after my road test.

My final thoughts.  With Spitfire MCs still readily available,  the Festiva conversion will probably not be the first choice in alternate master cylinder conversion for the Europa . Most of the effort with the Festiva MC was as a fabrication exercise, seeing if it would be possible to overcome the issues needed to adapt it to the S2. A more detailed explanation with additional photos is available in my Dropbox account at:

https://www.dropbox.com/s/1ttog0n2pp21r10/Adapting%20a%20Ford%20Festiva%20master%20cylinder%20to%20a%20S2%20-V2.odt?dl=0

Joji Tokumoto
Fallbrook, Ca

[EuropaTC]

Hi Joji,

Good photos on that Dropbox link, very sharp & clear.  I'm all in favour of these sort of mods, using alternative parts to keep our cars on the road seems a great idea, especially as if they are modern parts they could well be more durable or at least easier to get hold of.

But, (and bearing in mind I haven't seen a lot of Europa variants) what on earth is all that linkage and extra box section part about ? Is it something that's on Federal cars to move the master cylinder away from the chassis ? All new to me and I'm wondering just how it goes together. Do you have a photo from the wheelarch with it all assembled ?

Brian

[Grumblebuns]

Hi Brian,

I had posted round eight photos to my thread but only one showed up. I'll see if I can add the rest of the photos.

In regards to the Federal and I suppose all LHD S2 master cylinder "mounting bracket" , it's needed to clear the steering rack. From the accompanying pictures, without the extension box, the reservoir will not clear the steering rack.
The photos are from my Ford Courier conversion but the MCs are similar in layout. The box is also angled to the left to clear the spare tire. On my Courier conversion, the lines entering the ports had less than a 1/4" clearance from the spare. It's the reason why I believe the factory used banjo fittings for the brake lines at the stock MC.

My little exercise gives a few more options in the future as part sources dry up.

Joji

[EuropaTC]

ahh, thanks for those later photos, I'd never have guessed it went into the front bodywork like it does. 

Your post is well timed, I've just spent ages trying to replace the steering bellows and ended up having to drop the master cylinder because it was very cramped and I was concerned over splitting the new bellows. A short adapter/spacer would make a lot of sense as my UK RHD car, like yours, has the cylinder very close to the rack.

Looking how low that reservoir is I think those residual pressure valves would work well there, the reservoir is probably equal height or even slightly lower than the front calipers ?

Brian

edit to add...    in your first post you mentioned that this option wouldn't be as easy as the Spitfire M/C alternative as that has the correct bolt pattern.  AFAIK the spitfire one is only available as a 0.7" bore and this Ford is a 0.75" non-stepped bore. So if you're not happy with the pedal travel of the 0.7" or decide to put larger piston or 4-pot calipers on the car, then the 0.75" bore is attractive to reduce pedal travel.

[Grumblebuns]

Morning Brian,

You've opened up a couple of new topics here. The LHD TC/TCS has a cast aluminum oval spacer to extend the MC past the steering rack to allow the reservoir to clear the rack. Looking at where the MC would have to be mounted on a RHD TC/TCS, space is tight to say the least. I remembered your posting on installing a Spitfire MC where you had to install a remote reservoir and some modification to the front bulkhead. You guys are pretty limited in what will fit in the allowed space. I have my TCS up on ramps so I took a quick look at the relative position of the stock MC to the calipers. The cylinder top of the Girling appears to be slightly below the bottom of the calipers, the reservoir top is just below the top of the caliper. AFAIK, no RPV required.

Looking at the underside of my TCS this morning gave me an idea of how to adapt the Courier or Festiva MC to the TCS. I removed my failed boosters years ago but kept the stock TCS MC. Once I get the engine swapped out, I plan on installing a smaller bore MC. I already have experience with the Courier and the Festiva swaps so I'll be going with one of those. New Spitfire MCs are fairly expensive over on this side, close to $100 each.

In regards to the 0.70" vs. 0.75" difference in bore size between the stock/Spitfire and the Courier/Festiva MCs. I wonder if it's possible to feel the difference in pedal pressure with everything remaining the same except for the MC bore size. When I converted 65/1086 to the Courier, pedal pressure felt slightly harder. I discounted that due to differences in pad material as compared to 65/2501* which had the stock Girlings.