Why don’t we see more 964’s with dual master setups?
#1
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Thread Starter
Why don’t we see more 964’s with dual master setups?
In going through all the possibilities for the 964 brakes and having read Bill V’s numerous responses about the master cylinder size- or lack of sizes- I started to wonder about the possibility of dual masters. It seems like a good solution all around- no booster needed, adjustable bias allowing for different settings to accommodate track conditions, street use, rain etc. Just to be clear I doubt I will ever go that way because I already have enough projects and need to get the brakes sorted as easily as possible.
Anyway it occurred to me that the dual cylinders are a good, if not the best, solution for many of us regarding the use of larger calipers as well as addressing bias. Dual masteres with adjustable bias are a better solution that simply removing the bias valve or even adding an adjustable valve. People go as far as adding CAE shifters, larger lighter brakes, fully adjustable dampers not to mention re-gearing and 10’s of 1000’s on engine work- but I have yet to see what seems like a very effective mod in terms of dual masters. Am I missing something? Is it because of the removal of ABS?
Interested to hear thoughts on this for sure. I did find one lonely facebook post by Rothsport racing:
https://d.facebook.com/story.php?sto...78&__tn__=%2Cg
Anyway it occurred to me that the dual cylinders are a good, if not the best, solution for many of us regarding the use of larger calipers as well as addressing bias. Dual masteres with adjustable bias are a better solution that simply removing the bias valve or even adding an adjustable valve. People go as far as adding CAE shifters, larger lighter brakes, fully adjustable dampers not to mention re-gearing and 10’s of 1000’s on engine work- but I have yet to see what seems like a very effective mod in terms of dual masters. Am I missing something? Is it because of the removal of ABS?
Interested to hear thoughts on this for sure. I did find one lonely facebook post by Rothsport racing:
https://d.facebook.com/story.php?sto...78&__tn__=%2Cg
#2
In going through all the possibilities for the 964 brakes and having read Bill V’s numerous responses about the master cylinder size- or lack of sizes- I started to wonder about the possibility of dual masters. It seems like a good solution all around- no booster needed, adjustable bias allowing for different settings to accommodate track conditions, street use, rain etc. Just to be clear I doubt I will ever go that way because I already have enough projects and need to get the brakes sorted as easily as possible.
Anyway it occurred to me that the dual cylinders are a good, if not the best, solution for many of us regarding the use of larger calipers as well as addressing bias. Dual masteres with adjustable bias are a better solution that simply removing the bias valve or even adding an adjustable valve. People go as far as adding CAE shifters, larger lighter brakes, fully adjustable dampers not to mention re-gearing and 10’s of 1000’s on engine work- but I have yet to see what seems like a very effective mod in terms of dual masters. Am I missing something? Is it because of the removal of ABS?
Interested to hear thoughts on this for sure. I did find one lonely facebook post by Rothsport racing:
Anyway it occurred to me that the dual cylinders are a good, if not the best, solution for many of us regarding the use of larger calipers as well as addressing bias. Dual masteres with adjustable bias are a better solution that simply removing the bias valve or even adding an adjustable valve. People go as far as adding CAE shifters, larger lighter brakes, fully adjustable dampers not to mention re-gearing and 10’s of 1000’s on engine work- but I have yet to see what seems like a very effective mod in terms of dual masters. Am I missing something? Is it because of the removal of ABS?
Interested to hear thoughts on this for sure. I did find one lonely facebook post by Rothsport racing:
#3
wouldn't it be easier to install adjustable brake bais valve like race cars have. https://www.maximummotorsports.com/A...orts-P687.aspx
#4
wouldn't it be easier to install adjustable brake bais valve like race cars have. https://www.maximummotorsports.com/A...orts-P687.aspx
#5
Rennlist Member
you can use a Tilton with ABS. With that car, I'm going suggest durability + adjustability is the reason. A friend has a 993 with a tilton setup. You can also add motorsport ABS to these (my shop has an M4 setup in a 993 they are building). You can also add an adjustable bias to the setup as it exists now. Will require some plumbing. The tilton setups with a balance bar are effectively infinitely adjustable and very fine grained.
Why? Well I'm not sure you can add assist with the tilton setups. (maybe you can?)> its sort of that line for full on race car vs. street balance.
Why? Well I'm not sure you can add assist with the tilton setups. (maybe you can?)> its sort of that line for full on race car vs. street balance.
#6
you can use a Tilton with ABS. With that car, I'm going suggest durability + adjustability is the reason. A friend has a 993 with a tilton setup. You can also add motorsport ABS to these (my shop has an M4 setup in a 993 they are building). You can also add an adjustable bias to the setup as it exists now. Will require some plumbing. The tilton setups with a balance bar are effectively infinitely adjustable and very fine grained.
Why? Well I'm not sure you can add assist with the tilton setups. (maybe you can?)> its sort of that line for full on race car vs. street balance.
Why? Well I'm not sure you can add assist with the tilton setups. (maybe you can?)> its sort of that line for full on race car vs. street balance.
The water cooled cars seem to be more in need of a better ABS than the air cooled. These cars are the ones that suffer from 'ice pedal", I've seen it on all models right up to 993GT3RS
In general I am really leary of most after market ABS changes, I've seen several Cayman/Boxster installs that were questionable at best. The best brakes i've seen on one of those cars was a dual master setup
#7
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Does anyone know the diameter and stroke of the 964 RD/LW twin brake master cylinders. It looks like they are the same with single outlet. Does not like it would be hard to set up. Are the lines run through the ABS unit or bypassed (ABS removed)?
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#8
19.05/17.78mm(3/4//7/10") also works giving the same bias ratio but changing the pedal ratio to 28.96 which is getting low for non boosted brakes, though a fit driver should be fine
#9
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Thanks Bill - you have such a great knowledge when it comes to Porsche brakes. The group is really luck to have your expertise available.
Follow up - could you/would you run the brake lines through the ABS or just by pass?
Follow up - could you/would you run the brake lines through the ABS or just by pass?
#10
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Thread Starter
If I recall correctly this car has no Abs. The trunk looks like a trunk should! -edit- take a look at the pic above!
And yes- I too consider myself lucky to have Bill on board! Thanks Bill!
pete
And yes- I too consider myself lucky to have Bill on board! Thanks Bill!
pete
#11
PS I just reran the #s, originally I forgot to change the rotor size and rear caliper piston sizes
the 19.04/17.78 gives a range of 1.338 to 1.991 w/ a pedal ratio of 31.15 this is right where you would want to be
the 17.78/15.88 gives a pedal ratio of 37.22, this works ok for normal use but is not desirable for hi perf/track use
the next stp up would give a pedal ratio of 26.8 this is again getting too low, it would take a lot of leg