Early Model to Late Model Brake Master Cylinder Conversion

SwerveMonkey

Well-Known Member
I am considering converting the brake system over given the lack of availability for early model parts, I'm not sure if anyone else has decide to take this path.
I thought that swapping over would mean less chance of being in the same predicament with my early model woes.

Tried to search through forums to see if anyone else has done this other wise I'd volunteer to do a write up of sorts detailing things.
partially have images ready to document the change as well.

UPDATE 02May24: Sourced a "bracket" from a local you-pull junkyard as well as ordered supporting pieces from DF.
One hurdle i have tripped on is the change from one size to another in the bolt size for one of the master cylinder ports.

UPDATE 10MAY24: most of the process has been posted below, if there are any corrections please add to the thread and I'll edit posts as necessary, Thanks : D
 
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SwerveMonkey

Well-Known Member
As mentioned in build instruction videos there are difference between early and late model master cylinders and respective supporting components.
The late model has a smaller gap between the ports for the reservoir... this will not matter much aside from having the correct adapter.

Swapping out the master cylinder forces the change in the brake booster as well...
Again the late model has a smaller footprint for the part that goes into the brake booster to be actuated...
the Early model cylinder has a 46 mm diameter whereas the late model's is shrunk to 43.6 mm.
also the length of the rod in the power booster is shorter in late models.

For the stand point of converting only whats needed, i retained the early model reservoir... If you do want to swap to the late model reservoir then DO NOT FORGET to order the reservoir relocation adapter too.
 

SwerveMonkey

Well-Known Member
unfortunately I do not have pics of the Early model brake assembly package...
From RIGHT to LEFT the following items will need to be sourced from either parts store, ebay, or a local junk yard...
  • Late Model Bracket - about 1/2" thick squarish peice that WILL stabilize the booster when used, in my case pulled from a 2009 non-SS model in a local you-pick yard
  • Compatible trim/year Brake Booster - package shipped by fellow builder, but also found in local you-pick yard
  • SS trim Master Cylinder - bought from amazon
    • angled fittings from Red Oak [sourced from DF ]
    • SS trim Master cylinder adapter w/retainer [ DF again ]
    • Brake Line Fittings - one salvaged from the old MC, one from the junk yard that matched
one thing to note on the fittings is that they are both the correct threading and size to fit the new SS Master cylinder; however, the hex-heads are different sizes
a bit annoying but with the proper preparations I am sure that these can be made to match.

HERE is a link with more detailed information about the brake line fittings...
 
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SwerveMonkey

Well-Known Member
With the components set and everything matching thus far, its time to prep for flange work
really all that is needed is just cutting off the flared ends of the existing lines to replace the fittings.
I didn't grab a picture but a mini pipe cutter tool (~ 9$) would work well... link from a quick amazon search.

I did grab a snapshot of the bit i used for de-burring, I hear that is very important to de-burr the end for a smooth transition/flare

For the flaring tool set i simply grabbed one of those lending tool sets from the local auto shop.
 

SwerveMonkey

Well-Known Member
As a side note, always remember to put the fittings on first BEFORE setting the flare...
I've stumbled so that you can fly :p

I made the mistake of attempting to do a bubble flare and it is NOT recommended...

took an educated guess that the master cylinder port needed a double flare since it was a conical profile when looking at it...

after actually reading the manual and taking some time to ensure that the lines were seated correctly in the tool...


the double flare conical profile fits up to the cylinder ports nicely
 

SwerveMonkey

Well-Known Member
Of course a flush & brake bleed is recommended as the system has been exposed to the air, and in my case exposed to a high humidity condition that may have caused the problem of having fluid in the Booster.

Not sure if the brake fluid was like this before having been exposed for the work period, but it definitely should not be this mucky ...
Be certain to also bleed the Clutch system as well if you have a manual
 
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