As you all know...been working on 3291R for a couple years...and I think it may be time to address the existing master cylinder issue...it slowly weeps fluid out (I think, through the rear seal...but...and, while I can bleed it to a solid pedal that lasts for a few months, obviously it's not a case of 'just keep doing it and it will get better.")
So...I've collected a bunch of candidate MCs:
1. OEM Toyota F10 pickup
2. TRW Triumph Spit slope top .70
3. Original TCS cylinder (slope top)
4. From my parts stash of breaking up 4 S2s...a couple of S2 masters in serious need of rebuild, with a spare new, in the box, S2 reservoir.
Now, having removed the boosters, I've a non-boosted brake system. I'm thinking that (assuming I will re-plumb and remove the excess bundy going to the back then returning to the front...) the most satisfactory results may be found by sending the S2 MCs out to Apple and resleeving/rebuilding to S2 spec (stepped bore, etc). However, I'm wondering if there is enough clearance to use the large reservoir (as on the S2), with its increased capacity, in place of the slope top original TC style without having to do fiberglass surgery.
The advantages to using the Lotus-spec MCs is that
1. There would be no need to do bundy splicing to account for the feed port location on the master...and if I can fit the larger reservoir without carving fiberglass...well, that would be a plus too (not that I'm against it in the goal of increasing the capacity....),
2. Removing the out-and-back tubing for the front calipers would simplify and remove multiple splices to account for the booster and PDWV removal, and
3. The bores are close enough by using the S2, (accounting for the different size of the rear brake cylinders) for the car's dynamics (as far as I can tell).
Open to thoughts.
