69 FJ40 Brake Master upgrade

[mrtodds77]

My old one line brake master cylinder went out. I wanted to upgrade it to two lines to separate front and rear. But I have very limited space between the firewall and the carb. The only 2 line master cylinder that would fit is the 75-80 version. But all the pictures show it with a booster. Can I use it without a booster or is it going to be too hard?

Also another option I considered was getting a line splitter or proportioning valve but not sure what to do or get. I think I am getting in over my head.

Any help would be appreciated.

 

[vcrusher]

My old one line brake master cylinder went out. I wanted to upgrade it to two lines to separate front and rear. But I have very limited space between the firewall and the carb. The only 2 line master cylinder that would fit is the 75-80 version. But all the pictures show it with a booster. Can I use it without a booster or is it going to be too hard?

Also another option I considered was getting a line splitter or proportioning valve but not sure what to do or get. I think I am getting in over my head.

Any help would be appreciated.

 

[vcrusher]

sorry was using my phone to reply press wrong button.
I bought the master cylinder kit from Man a fre for my 1969 with stock engine. I installed all disc brakes and upgraded all my lines, no booster. Easy to install and no issues stopping.

 

[65swb45]

Here’s a pic of the Mark’s Off Road non-booster firewall adapter on my 69 FJ40

No clearance issues

 

[mrtodds77]

That kit is 350. I got the other master cylinder for $89 from cool cruisers. Not sure what those in line blue things are in their kit? The Jegs proportioning valve is only $30. I’m staying stock drums for now. Got all the 10mm to 3/16 brake line Adapters from Napa for $15. I got 50 ft of NiCopp lines for $25. Not sure those blue inline things are worth $200.

 

[mrtodds77]

That looks like the stock 70-75 brake master. That won’t fit in mine because I have the Holley carb that sits a little closer to the firewall. But you ran that without a booster when the manual shows a booster for that kit originally. So that gives me hope that I can run the 75-80 brake master without a booster.

 

[65swb45]

Can’t speak to fitment with a Holley; it’s definitely a fatter carb.

I’ve never seen a kit on my website, but the adapter is still on the Specials page at $40.

 

[mrtodds77]

Thanks Mark, I saw that and wondered why I couldn't just drill out the firewall but if it allows me to reuse my brake push-rod that is a definite plus. I am really tight though, I think I have 1/8 of an inch between my outer fill bowl and my Holley Air Cover. That nice looking nimble adapter looks like 1/2 inch thick. I will have to re-measure. I will post pictures of what I have. I see that you used that master cylinder without a booster. Does a booster make that much of a difference? Do you think I will need a Jegs Proportioning Valve or something similar? I am keeping all my stock drums for now.

 

[mrtodds77]

 

[mrtodds77]

Cool Cruiser's makes this one too. It's a little more but it might solve my space problems. Only one bowl to keep track of. It says good aftermarket for 80-90. Mark do you think this would still work without a booster?

 

[65swb45]

I would definitely stick with the MC you have and try to find one of @Downey aluminum air cleaners that offsets the filter away from the MC.

 

[FJ40Jim]

Do the brakes work OK now, in terms of pedal effort?
If yes, then stay with a 1" bore MC.

If the pedal is too soft, truck stops too well, go to the 1-1/16" MC off a later big toyota (T100? Sequoia?)
If the pedal is too firm, drop down to a 15/16 (1-ton minitruck) or 7/8 MC (Cruiser, mini).

Pic of a 1" MC off 92? 4Runner on early firewall, no booster, plenty of clearance.

 

[mrtodds77]

Thanks for the wise advise and pictures. The breaks worked fine in terms of effort using the old 1” master cylinder. I just don’t feel safe with a one line MC especially off road where I can easily brake a line or spring a leak. I like the look of the two bowl MC. You have the 90+ MC without a booster so I think I should be ok. My grand mother may not be able to drive it but I am ok with that.

 

[Archie 1962 FJ25]

Even better use 92-94 Toyota Camry brake master (ABS model), these are 1” bore and OEM Toyota. Best part you get to keep 3 bolt pattern on firewall. You can convert single reservoirs to dual as well. Holes on firewall may need slight modification but end result will be a purity.

 

[mrtodds77]

Interesting Option. The three bolt pattern looks larger than the earlier style. It would be hard to modify those to be a little larger? Can you expand on what mods you had to do there?

 

[FJ40Jim]

The holes are about one hole diameter off. The weldnuts have to be knocked off the firewall, holes closed, new holes drilled, new weldnuts installed. Not difficult, but takes a while. It's why I chose the $50 adapter & 4bolt MC. Saving myself several hours of fab time was worth more than $50. For a person that likes to cut & weld, or is going for the most OE appearance, the 3-bolt is a good way to go.

 

[mrtodds77]

Ok that’s not going to work for me. I am not a welder. If the triangle holes don’t match exactly then it’s much easier to go with the 4 bolt adapter and enable myself to go with a lot more OE options. Thanks Jim

 

[Rigger]

I bought the two bowl master from @65swb45 along with his firewall adapter. No booster. I’m happy with the brakes. I do have four wheel discs though, so different from your setup. I hope this helps.

 

[mrtodds77]

Ok. That’s almost the same setup I am going to try to install. I am glad you like the breaks and no booster needed. Thanks for sharing your picture. Looks like you converted from 10mm to 3/16 on the break line out of the MC. What did you do connecting to the first 9mm connector?

 

[Rigger]

Looks like you converted from 10mm to 3/16 on the break line out of the MC. What did you do connecting to the first 9mm connector?

I went with all new brake lines. My prop valve is American thread and everything else is 10 mm metric.