Chevy Booster and Master Cylinder on FJ40

[Chipcraft]

Hey There,
I just picked up a `69 FJ-40 which I'm in the process of finishing a restore. I'm reworking the brakes and was wondering if anyone had ever used a Chevy Booster and Master Cylinder on an FJ40. Does anyone make the firewall adapter and pedal linkages for this application?

thanks!

 

[dgangle]

First, a 'restore' doesn't use anything but FJ40 parts correct for a particular vintage. I think you are talking more about a resto-mod.

I looked into this a while back but using Toy booster. No exp on the GM/GM deal but if you are interested in what I found out, please read on.

Several companies make an adapter to go from a Toy booster to a GM MC.

Rockstomer makes this



Sky Mfg makes this



or one can make their own like this



What attracted me to it was these MC's are CHEAP. However, I could find no one that used one of these with anything but Dana axles under their Toyota FJ40 or minitruck. Additionally no one could tell me the pressures developed or the presense of residual valves.

What axles and brakes do you have or plan to run?


here's some read:
http://home.4x4wire.com/erik/4runner/brakes/
http://www.sky-manufacturing.com/new/detaproduct.php?id=233
http://www.sky-manufacturing.com/new/detaproduct.php?id=216
http://rockstomper.netfirms.com/sho...alog/product_info.php?cPath=22&products_id=65
http://www.4wdandsportutility.com/tech/0904_4wd_2001_toyota_tacoma_prerunner/index.html

 

[Tankota]

Holy Crap dangle! That's impressive how much info you presented. I'd give you a gold star for this post!

Okay, back to the original post. I tried a chevy truck booster and MC after seeing an old school local guy who ran a buick 455 in his cruiser since the early 70s had one on his. Had to drill new holes in the firewall and the thing never quite worked right. Ended up using a toyota pickup one which goes through the original holes in the firewall. I had stock axles which is why I don't think it worked right...brake pressures and volumes may not quite match up.

 

[fieldsken1]

man a fre sells the booster master and adaptor

 

[fieldsken1]

man a fre sells the booster, master and adaptor

 

[Tankota]

Oh, and I used one out of a blazer (booster and MC) so it stuck so far out that the MC was almost even with the front end of my SBC valve covers. Looked a bit out of place.

 

[kyot4x4]

i used a M/C from a corvette with a 1 inch bore and a 7inch double diaphragm booster from a hot rod shop. i have 4 wheel disk brakes. the corvette master is for disk brakes. no residual check valves. i mounted the booster on the firewall just had to drill new holes for mounting.

kyle

 

[Chipcraft]

Wow! Thanks for all the information. I am using the stock axles with disk brakes. I'm starting from scratch, as I have no lines run or anything yet. Here is my "canvas":

Here is the booster / MC I could use if it will work (not sure what it came off of):

Ideas?

 

[60fj25]

With your style firewall rib you will need to space the booster out from the firewall. The spacer is basically a piece of pipe sandwiched between two flanges, one with the toy bolt pattern, the other with the chevy. I needed to make a smaller adapter for the clutch master which shows up better on the pics (FJ40 mc to FJ25 firewall)

Any muffler, brake, machine shop should be able to make the adapter. You are on your own to make a longer actuating rod.

 

[Chipcraft]

Based on the posts made so far it sounds like an adjustable pressure divider between the front and back is a must. Any recommendations?

 

[Combat Chuck]

The booster you've snagged looks like its out of a mid-eighties Suburban (I've got an identical one sitting in my parts pile) As far as a "divider" goes, you have two ports for two sets of brakes, so what you may need is a proportioning valve to make sure the front brakes get the better pressure. Wilwood makes a good one, as does Jeg's, or just about anything from Summit Racing should work. Just make sure it's adjustable. You'll also need a whole mess of adapters to get the brake lines to mate up.

 

[Chipcraft]

I found this firewall adapter on jtoutfitters.com it looks to be what I need to get started.

Toyota Early FJ40 45 Land Cruiser Brake Booster Adapter - JTOutfitters

 

[Chipcraft]

Should I use 1/4" tubing for front and back lines?