alternate master cylinders/swaps

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Piledriver
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alternate master cylinders/swaps

Post by Piledriver » Fri Aug 03, 2018 10:52 pm

Looking for a list of source vehicles or (preferably) part numbers for larger bore master cylinders.

I know the late Bus masters (22mm/22mm) are a good option in an iron master cylinder.
From memory (and other posts) they need the pushrod shortened about 10mmish.
22 or 23mm is about the right range for my setup, brembos out back (2x28,2x30) with padgid factory pads, wilwood superlites out front(4x31.75") with pfc14s..

I'd personally prefer an aluminum master as they seem a bit more (internally) corrosion resistant.

Some of them may need the pushrod shortned, or nuts on the master side and such.

I'm lookin at it as my setup works awesome, but the travel is a bit more than I'd like, and the pedal effort is actually too low for my taste.
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Ian Godfrey
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Re: alternate master cylinders/swaps

Post by Ian Godfrey » Sat Aug 04, 2018 3:07 am

coolrydes (Mendeola) has a aluminium master cylinder that is close to your description
https://www.coolrydescustoms.com/store/ ... INDER.html

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davidt
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Re: alternate master cylinders/swaps

Post by davidt » Sat Aug 04, 2018 3:28 am

Hi, you could try changing the brake pedal ratio. This requires you to cut of the plate that the push rod connects to and weld on a longer version. This will increase your pedal effort and reduce the pedal travel. I fitted vented front discs with Volvo 4-pots, rear discs with Suzuki SX4 rear calipers and a 68-69 L/H/D T2 master cylinder into my R/H/D 1302 Superbug. I still had about 2-3in of pedal travel but after changing the pedal ratio, I now have about 1in of travel and a nice firm pedal which gives great brake modulation and control.
Hope this helps as it is a great mod.
Hooroo

David Thiele

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Lanner
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Re: alternate master cylinders/swaps

Post by Lanner » Sat Aug 04, 2018 11:33 pm

The mendeola one is a vw mk4 golf mc..

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Piledriver
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Re: alternate master cylinders/swaps

Post by Piledriver » Wed Aug 08, 2018 2:33 am

Lanner wrote:
Sat Aug 04, 2018 11:33 pm
The mendeola one is a vw mk4 golf mc..
Thanks for that, precisely the sort of info folks need to know to make purchase decisions.

I'm hoping to put some part#s to the various compatible masters, and what caliper they would be best used with.
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Piledriver
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Re: alternate master cylinders/swaps

Post by Piledriver » Wed Aug 08, 2018 10:43 am

OK, std power Mk4 masters are 19mm, so the larger bore version seem to be for manual brakes or a big brake mk4, gtI/GLX, vr6 critters etc.
The -90 cabriolet master looks ~identical to the Mk4, but is 13/16" bore. (likely same as Mk1 GTI)


VR6 critters (GLX et al) get the 23.8mm bore version,
Vanagons had 23.8mm, with horizontal flange. 251611021C
Looks like late bays were 23.8mm too. 211611021
(earlier) Bay busses 22mm
-90 Cabriolet, 20.6mm
Stock late T1/T3 19mm
The water cooled masters have an angled flange like a 1302/1303 so some mods needed to car to install depending on target.
All these can be had from $35-$180 depending on brand and supplier.

It appears that some Mercedes use the same masters as VW, and may have a 25mm flavor, Googleresearching...

I will come back and add part numbers if someone doesn't beat me to it.
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H2OSB
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Re: alternate master cylinders/swaps

Post by H2OSB » Wed Aug 08, 2018 5:24 pm

Pile--

I'm trying to confirm the 19mm size for the MK4 MC with the angled flange. Can you link?

I certainly don't need anything larger than 19mm for my brakes, however, I would interested with regard to quality and corrosion resistance

H2OSB

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Re: alternate master cylinders/swaps

Post by Piledriver » Wed Aug 08, 2018 6:55 pm

https://www.dormanproducts.com/p-78223-m630833.aspx is an example.
non-abs.
If you are staying at 19mm, I would only consider the swap if replacing the master anyway, as the lines will need adapted for layout.
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H2OSB
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Re: alternate master cylinders/swaps

Post by H2OSB » Wed Aug 08, 2018 8:53 pm

That's 23.8mm

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Piledriver
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Re: alternate master cylinders/swaps

Post by Piledriver » Wed Aug 08, 2018 11:06 pm

My bad, thats the non-abs one.
The "normal" ABS ones are apparently 19mm.
Dormans website has search.

I will probably end up with a late bus or vanagon 23.8mm unit as it will bolt in a T3.
I'll try to find an aluminum version.
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H2OSB
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Re: alternate master cylinders/swaps

Post by H2OSB » Thu Aug 09, 2018 12:02 am

The Dormans site is nice, and yet, confusing. When searching for the part in question, in my case, I used a 2003 Golf, four parts were listed. Basically, one with bore of 3/4ths and one with a bore of 15/16ths. Then each is offered with a new reservoir attached. However, if you scroll all the way to the bottom for the specs list the bore of each as substantially larger (relatively speaking).

Confused
H2OSB

DerrickfromNC
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Re: alternate master cylinders/swaps

Post by DerrickfromNC » Thu Aug 09, 2018 5:48 pm

Here is some discussion from GermanLook.com regarding the use of 944 and 911 turbo MCs
https://www.germanlook.net/forums/showthread.php?t=9444

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Re: alternate master cylinders/swaps

Post by TZepeSH » Sat Aug 11, 2018 12:32 am

I've been also reading on master cylinders to use with the 944t brakes. On germanlook, the most consider using the stock 19mm pump ok. However the original Porsche pump is 23.8mm, so I would rather consider a larger pump and mechanical booster.
Now with the 944na brakes I like the softer feeling and longer pedal travel using the bug pump. I wouldn't mind the same for the 4 pot. I also had 944 pump and I felt like I had less brake control with the harder pump.

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