Outer Limits 4x4 Board

Ok guys just needing to know what Master cylinder i need to run in a mates 45 series.
I have searched and am getting some conflicting info.

It has a 60 series front diff in it ( with discs obviously) And i am about to fit a rear 60 diff so it will have the single cylinder brakes on the rear.
The car is a 73 model with a 2f in it with a twin cylinder master.
Is a 60 series booster and master able to be fitted and what is involved.
Or is there an easier solution.

Cheers Nottie

a 60 series master should bolt to a 40 series booster (did in my rig).

there are all sorts of options like removing residual valves from the front circuit etc... but end of the day, using what was engineered in the factory for those brakes is probably best.

dunno if the booster bolts up to a 40 firewall tho.

I have just done the same to my 45. Left the 45 booster as is and got a new master cylinder from a 60 series and bolted to it. Brakes work a treat.

greg

Cheers Guys
Thats what i had in mind to do but thought maybe a 60 booster might have been bigger.
Anyways ill be off to get a 60 MC then the whole brakes will be pretty much 60 series
Cheers

60 booster is bigger, not sure if its required though. I did 60 front disc conversion, 60 rear drum conversion (just to get rid of those annoying twin cylinders) and used 60 booster, master and proportional valve. I used the booster because I had one handy and it made sense to keep the whole brake system as per 60. Would probably be fine with the 45 booster though.

If you do decide to fit a 60 booster you'd need to bend the curved lip on the firewall brace so its straight to clear the bigger booster. Also because the master cyl mount is not centered on the booster you'll have to mount it upside down or it will foul on the bonnet lip. You can see i the pic how snug a fit it is.



Also as you can see in the pic you'd need to loosen off the booster to get the clutch master off if you need to replace it as the booster covers a portion of it.

When I did my front and rear disc conversion on my 40, I used the master and booster that was in there.. Just removed the residual valves and away I went.. Too easy.. The master bore is 1 1/8 inch, so pedal effor is a bit high, eventually I'll change to a 7/8 master for better pedal feel.. I suspect the 60 setup is similar to my 81 40s factory front disc, theres a combnation valve under the master cylinder on the booster, I believe this handles residual pressures, pressure differential warning switching and proportioning.. Maybe this could be adapted to your application..