March 31, 2005
Glenn,
I’m slowly progressing through my project of combining three 1800s into one car. I have a running 1967 with decent body and interior, and two parts cars, a 1968 or ’69, and a 1970 1800E. I have completely stripped the 1800E and the shell just left my driveway (my wife now speaks to me again – is that good or bad?). The 68/69 is nearly stripped and will be leaving on a flatbed, too, in the next week or so.
The fuel-injected B20 and rear with 4-wheel disks from the 1800E will eventually be going into the 1968. I plan on retaining the original transmission with the hydraulic clutch and original driveshaft to ease the conversion. My biggest issue is going to be converting the brakes and master cylinder. I read your posts regarding the early (pre-1968) versus later (1800E) set-ups, and your reference to the 1969 model with dual circuit system for front disks and rear drums with rear pressure reducing valves. There must have been a series of evolutionary changes between 1967 and 1970 with the braking system, as my 1968 model has another configuration…
My 1967 has the early-style, single chamber master cylinder on firewall, with remote vacuum assist, and single circuit, as illustrated in the Haynes manual. My 1970 has the late-style, dual chamber master cylinder with the vacuum assist mounted on the firewall, and dual circuit with rear pressure reducers, also as shown in the Haynes manual. However, my 1968 is very odd – there is a double chamber master cylinder on the firewall, with remote vacuum assist. One chamber of the master cylinder leads to the rear brakes (through the brake light switch) without power assist or pressure reducing valves. The other chamber leads through the servo assist, then through the brake switch and to the front brakes.
The thought of modifying the 1800E master cylinder with power assist to the 1967 seems intimidating (as I think it would require re-engineering the brake pedal assembly and firewall mounting). I was wondering what your thoughts (or other readers') might be on using a combination of the 1968 and 1970 setup. My thought is to use the 1968, dual chamber (firewall mounted) master cylinder with remote vacuum assist unit, and similarly run one chamber (without power assist) to the rear disk brakes – I’m thinking that without the power assist, the rear pressure reducing valves won’t be necessary (this is the same as the current 1968 setup but with disks instead of drums). I would then run the other chamber through the remote power assist, through the 1970 splitter block and to the 1800E front disks. This would be more of a one and a half circuit system than a dual circuit system; but may be a good compromise. Any thoughts would be appreciated.
Thanks,
Kevin Wheeler
1800S + 1800E = 1800SE?
Kevin - It's true that the brake system went through several changes from '67 to '70, but I have a feeling the arrangement on your '68 is not stock. If you'll send me the chassis number of the car, I could look up the equipment in the parts book and tell you what it should have. It could be a transition model, or possibly someone with an eye for practical safety replaced an early single-circuit master cylinder with a dual master cylinder and connected the pipes according to handyman logic. It doesn't matter much whether it is stock as long as it works, but if the car is a parts car, you probably haven't given it a thorough test drive. I would proceed with caution on any non-stock brake system plan, and have a backup plan if it turns out not to work as well as it should.
I would be hesitant to try putting the '70 system on the '67, because as you probably noticed, the fastener array at the firewall is different. You could cut the pedal boxes out of both cars and weld the box from the '70 into the '67. Or you could drill new holes in the pedal box and strenthen the box if necessary by welding in a support plate and/or by welding up the holes from the previous fasteners. This all seems like a lot of work when you can simply use an earlier system that bolts in without modifications. -Glenn.