I've got a 67fj40. What is the easiest and best way to convert my single circuit master cylinder to a dual circuit? Keep in mind that I have all new 9mm steel/rubber lines. Did toyota make a 9mm dual circuit master that I can bolt up to the firewall. I know some plumbing will have to be done as well. May need some ideas on that too. Thanks!
How to convert a single to dual master cylinder (1 Viewer)
- Thread starter 67FJ40
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Primarily, follow you brake lines from the MC and find the spot that is easiest to separate the rear from the front.
I have done two different versions. The first is that I adapted a corvette master cylinder to a 67 FJ45. I ran a new steel line to the tee on the passenger side that goes to the rear. I replaced the tee with a right angle fitting from a later model FJ40. The front axle line I ran directly from the MC.
l have also done power on the same generation vehicle. The biggest problem is moving the vacuum booster away from the brace in the firewall. I fabricated a standoff bracket that would move the booster out from the firewall to clear the brace. From there, the plumbing was the same as noted above on the manual system. JT Outfitters has a extension bracket similar to the one I built. The use a minitruck booster. I used the late model FJ40 booster from the 1977 period.
Lastly, one of my customers had someone build their brake system and they just cut the firewall brace out and mounted the booster directly on the firewall. I didn't care for that method, opting for the extension bracket.
All of these systems work fine.
Don
I have done two different versions. The first is that I adapted a corvette master cylinder to a 67 FJ45. I ran a new steel line to the tee on the passenger side that goes to the rear. I replaced the tee with a right angle fitting from a later model FJ40. The front axle line I ran directly from the MC.
l have also done power on the same generation vehicle. The biggest problem is moving the vacuum booster away from the brace in the firewall. I fabricated a standoff bracket that would move the booster out from the firewall to clear the brace. From there, the plumbing was the same as noted above on the manual system. JT Outfitters has a extension bracket similar to the one I built. The use a minitruck booster. I used the late model FJ40 booster from the 1977 period.
Lastly, one of my customers had someone build their brake system and they just cut the firewall brace out and mounted the booster directly on the firewall. I didn't care for that method, opting for the extension bracket.
All of these systems work fine.
Don
Search should reveal lots of threads on this topic, some quite detailed. I've never heard of a 9mm dual master. You will likely need to use either some custom brake lines (9mm fittings on one end, 10m on the other) or adapters.
When I did mine the first time. I cut the brace on the fire wall. It looked good and did not go that bad. I got into bigger tires and more wheeling and changed it. I thought it flexed the fire wall. I fixed the brace and made an adapter for the fire wall. I would up running all ne brake lines as well. Like it was stated above I had to make my own lines to go from 10mm to 9mm. I would never cut the brace again if I do another conversion.
it would be nice if JT, Cruiser Corps or one of the suppliers would put together a conversion kit for the older cruisers- i bet they would sell quite a few of them- include everything- lines, fittings, MC, booster and bracket.. beats having to peice together a bunch of parts and have to worry about it they work or not-
i gladly paid SOR an arm and a leg for thier 9mm brake line kit when i re plummed my 67-
i gladly paid SOR an arm and a leg for thier 9mm brake line kit when i re plummed my 67-
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- #7
Thats what I was thinking. I just bought all new steel lines and rubber lines from SOR to redo the whole system. I wish someone would put together a MC and adapters for a upgraded dual circuit system. I would think Mark or SOR would do it. Probably sell a butt load. I would buy it for sure.
hmmm, have you contacted Mark?
I cut my firewall rib, would not do it again. With how heavy duty the brackets are to hold the steering wheel and pedal that firewall rib was doing nothing. My bigger problem was the stud for one side of my geo metro booster hit the support bracket in the drivers compartment, causing a big headeache cutting out enough space to put the nuts one. I would go with the adapter. My concern was how close it put my setup to the carb, I layed it out both ways and decided against the adapter, but wish I had gone that route do to my mounting issues. Happy with the end result.
2x on planning to do all new brake lines. Once I decided to replace the axles and put in a dual circuit I decided to replace all the brake lines at that time. When removing the old ones that were working fine I was shocked at how easily the cracked and crumbled when I tried to move them.
2x on planning to do all new brake lines. Once I decided to replace the axles and put in a dual circuit I decided to replace all the brake lines at that time. When removing the old ones that were working fine I was shocked at how easily the cracked and crumbled when I tried to move them.
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- Thread starter
- #12
I've not contacted him yet but have looked into it on his web site. I know, its probably best to just give him a call.
- Thread starter
- #13
9mm junctions needed
Any of you guys have any 9mm brake line junctions you would like to sell? I have a post in "wanted parts" but not gettin much feedback.
Any of you guys have any 9mm brake line junctions you would like to sell? I have a post in "wanted parts" but not gettin much feedback.
