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vs brake upgread to vt brakes

RX25SE

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Im running the VS booster with a VT master.

The pedal is not long and spongy.

The VT master has a shallower hole in the primary piston and must be spaced away from the VS booster to retain normal pedal height/feel. As the VT master has a larger bore, the pedal will feel firmer than the stock VS system. (I fitted the VT master first to see how it would feel with VS calipers/discs and almost left it at that. Good pedal feel)
If you retain the smaller VS master the pedal will be low and spongy due to the larger amount of fluid required by the twin piston calipers.

Fitting a VT master to a VS booster without a spacer between will prevent the compensating port in the master from opening and the master can't work correctly.
 

HamaTime™

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Im running the VS booster with a VT master.

The pedal is not long and spongy.

The VT master has a shallower hole in the primary piston and must be spaced away from the VS booster to retain normal pedal height/feel. As the VT master has a larger bore, the pedal will feel firmer than the stock VS system. (I fitted the VT master first to see how it would feel with VS calipers/discs and almost left it at that. Good pedal feel)
If you retain the smaller VS master the pedal will be low and spongy due to the larger amount of fluid required by the twin piston calipers.

Fitting a VT master to a VS booster without a spacer between will prevent the compensating port in the master from opening and the master can't work correctly.

There's always one to post conflicting opinions.

Did you try it yourself, did you do the brake upgrade??

I did, and I used the VT Master Cylinder/VS Booster combo along with the RaceBrakes spacer that goes between the two. Read my thread to which I posted the link above with the problems I had with it. The whole system was Taken off, inspected, re-fitted, bled about 4 times and it still had the worst pedal feel, long and spongy.

VS brakes with the VT master??? What's the point? Retaining the ineffecient and small single piston calipers? Bad idea.

In short, I tried and tested the VS Booster with the VT Master Cylinder combo for over one and a half months and it was the worst.

Spend the extra cash and get the larger, steel, twin diaphragm VT Booster which was designed to run with the rest of the equipment. Best choice I ever made going to the VT Booster.
 

RX25SE

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There's always one to post conflicting opinions.

Did you try it yourself, did you do the brake upgrade??

I did, and I used the VT Master Cylinder/VS Booster combo along with the RaceBrakes spacer that goes between the two. Read my thread to which I posted the link above with the problems I had with it. The whole system was Taken off, inspected, re-fitted, bled about 4 times and it still had the worst pedal feel, long and spongy.

VS brakes with the VT master??? What's the point? Retaining the ineffecient and small single piston calipers? Bad idea.

In short, I tried and tested the VS Booster with the VT Master Cylinder combo for over one and a half months and it was the worst.

Spend the extra cash and get the larger, steel, twin diaphragm VT Booster which was designed to run with the rest of the equipment. Best choice I ever made going to the VT Booster.


Yes there are always conflicting opinions. Especially when the information posted is incorrect.

I have been running the VT brakes for over 3 years and have converted other cars as well, so yes, I have done it.

I machined my own spacer for the master and have never had an issue with pedal feel.

When we did a mates car (before mine) we thought we'd try it with the VS 7/8" bore master and booster (knowing full well that the pedal would be lower and softer) seeing we had both driven a VS with a 15/16" master and the pedal was acceptable. Not so with the VS master so we fitted a VT master.

When I did mine I knew what to expect so I'd thought I'd try fitting the VT 1" master before the calipers to see how the pedal would feel. Much faster reaction and a firmer pedal as you would expect. (remember that Police spec VK used to fit 1' master instead of 15/16" and retained the single piston calipers.)
I was tempted to leave it at that, so no, not a bad idea.
Have you driven a VS with this setup??

I'm not disputing that a VT booster will be a further improvement, but using a correctly fitted VT master to the VS booster will not cause a low spongy pedal.
 

HamaTime™

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Yes there are always conflicting opinions. Especially when the information posted is incorrect.

I have been running the VT brakes for over 3 years and have converted other cars as well, so yes, I have done it.

I machined my own spacer for the master and have never had an issue with pedal feel.

When we did a mates car (before mine) we thought we'd try it with the VS 7/8" bore master and booster (knowing full well that the pedal would be lower and softer) seeing we had both driven a VS with a 15/16" master and the pedal was acceptable. Not so with the VS master so we fitted a VT master.

When I did mine I knew what to expect so I'd thought I'd try fitting the VT 1" master before the calipers to see how the pedal would feel. Much faster reaction and a firmer pedal as you would expect. (remember that Police spec VK used to fit 1' master instead of 15/16" and retained the single piston calipers.)
I was tempted to leave it at that, so no, not a bad idea.
Have you driven a VS with this setup??

I'm not disputing that a VT booster will be a further improvement, but using a correctly fitted VT master to the VS booster will not cause a low spongy pedal.

I hope your not referring to my information posted as being incorrect, since my information is based on real life experience and fitting it myself...therefore not incorrect.

Well I'm glad you have first hand experience with the upgrade. Makes our conversation a bit more credible since we both know what we are talking about now.

What diameter did you machine the spacer? The one from Racebrakes if I remember correctly was 25mm Performance Brake Packages (bottom right of the screen)

I don't doubt that the VT master running with the VS calipers would provide a faster reaction and less spongy pedal, due to the larger bore and being able to push a greater volume of fluid faster, but still that is improving pedal feel and reaction, it will not really improve the efficiency of the brakes. Due to the fact that you are still only getting 1 54mm Piston down onto a 288X23mm Disc....whereas with the twin 42mm Pistons on a 296X28mm disc running with a 1" Master and a twin diaphragm steel booster. Even the theory makes it sound so good, doing the whole upgrade to me is the best decision.

I have driven a VS with stock calipers running a VT master, I have driven a VS with VS booster/VT master (all correctly fitted, fiddled with and trialed to try and get it to work....nothing)

I have had a bad experience with the VT master/VS booster, and I won't recommend it to anyone.

I will also dispute your last statement, as a correctly fitted/spaced VT master/VS Booster combo caused a spongy free play pedal which had no effect on the top 40% of the pedal (aka the free play threshold) and then kicked in.
 

RX25SE

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Here's a pic of the spacer.

IMG_6380.jpg


From memory it was about 6mm thick (I also made a spacer to fit inside the booster at the rear of the primary piston) and I also refitted the VS reservoir.
I calculated the distance from the end of the booster pushrod to the bottom of the bore in the piston and used that distance for the spacer. My mates has no spacer as he just removed the adjusting nut from the pushrod, but I don't recommend this as it will not have a rounded end and will, over time, butcher the bore in the piston.

This setup allows the master cylinder to instantly build pressure the moment the pushrod is moved. No low or spongy pedal.

Perhaps the spacer supplied (in the pic from your link) was too thick? This would cause a very low pedal.
 

ephect

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noones mentioned the shims needed for the VT rotor hubs. These are not needed if you purchase the modified vt rotor with vs hub.

there is a how to also on here
 

justbad4you

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I hope your not referring to my information posted as being incorrect, since my information is based on real life experience and fitting it myself...therefore not incorrect.

Well I'm glad you have first hand experience with the upgrade. Makes our conversation a bit more credible since we both know what we are talking about now.

What diameter did you machine the spacer? The one from Racebrakes if I remember correctly was 25mm Performance Brake Packages (bottom right of the screen)

I don't doubt that the VT master running with the VS calipers would provide a faster reaction and less spongy pedal, due to the larger bore and being able to push a greater volume of fluid faster, but still that is improving pedal feel and reaction, it will not really improve the efficiency of the brakes. Due to the fact that you are still only getting 1 54mm Piston down onto a 288X23mm Disc....whereas with the twin 42mm Pistons on a 296X28mm disc running with a 1" Master and a twin diaphragm steel booster. Even the theory makes it sound so good, doing the whole upgrade to me is the best decision.

I have driven a VS with stock calipers running a VT master, I have driven a VS with VS booster/VT master (all correctly fitted, fiddled with and trialed to try and get it to work....nothing)

I have had a bad experience with the VT master/VS booster, and I won't recommend it to anyone.

I will also dispute your last statement, as a correctly fitted/spaced VT master/VS Booster combo caused a spongy free play pedal which had no effect on the top 40% of the pedal (aka the free play threshold) and then kicked in.

ok im a tiny bit confused? so vt master? vt calipers? but no need for a booster? (and if 1 is iftted is it a straight bolt on? for the booster.) im sourcing all my parts on monday for the job on the maloo on wend? booster or not? i didnt have a vt booster on my old vs(the pedal on that upgrade was 75%good....not like the stopping power of mt vt berlina but not bad)
 

HamaTime™

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From memory it was about 6mm thick (I also made a spacer to fit inside the booster at the rear of the primary piston) and I also refitted the VS reservoir.
I calculated the distance from the end of the booster pushrod to the bottom of the bore in the piston and used that distance for the spacer. My mates has no spacer as he just removed the adjusting nut from the pushrod, but I don't recommend this as it will not have a rounded end and will, over time, butcher the bore in the piston.

This setup allows the master cylinder to instantly build pressure the moment the pushrod is moved. No low or spongy pedal.

Perhaps the spacer supplied (in the pic from your link) was too thick? This would cause a very low pedal.

I'll go measure it later today and edit this post. The pedal feel may be improved, but compared to the VT booster which obviously allows a bigger pressure output than the smaller VS one, pedal feel will be better than with the VS Booster/VT master combo.

noones mentioned the shims needed for the VT rotor hubs. These are not needed if you purchase the modified vt rotor with vs hub.

there is a how to also on here

Yeah your right mate, forgot about them. I'd stick with the standard VT rotors with the hubs, allows more flexibility down the track.

ok im a tiny bit confused? so vt master? vt calipers? but no need for a booster? (and if 1 is iftted is it a straight bolt on? for the booster.) im sourcing all my parts on monday for the job on the maloo on wend? booster or not? i didnt have a vt booster on my old vs(the pedal on that upgrade was 75%good....not like the stopping power of mt vt berlina but not bad)

No you need the VT master, and you will need the VT Booster, yes it's a straight bolt on, however, contact MarkoVR (fellow JC member) for his custom VT Booster Mounting bracket. You will need the bracket to bolt the VT booster onto your VS firewall since the mounting studs/platform is different.

Definately go with the VT Booster, 100% pedal feel.
 

justbad4you

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ok thanks for the info that clears it all up forme...thanks again....havea good1,
I'll go measure it later today and edit this post. The pedal feel may be improved, but compared to the VT booster which obviously allows a bigger pressure output than the smaller VS one, pedal feel will be better than with the VS Booster/VT master combo.



Yeah your right mate, forgot about them. I'd stick with the standard VT rotors with the hubs, allows more flexibility down the track.



No you need the VT master, and you will need the VT Booster, yes it's a straight bolt on, however, contact MarkoVR (fellow JC member) for his custom VT Booster Mounting bracket. You will need the bracket to bolt the VT booster onto your VS firewall since the mounting studs/platform is different.

Definately go with the VT Booster, 100% pedal feel.
 

RX25SE

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I'll go measure it later today and edit this post. The pedal feel may be improved, but compared to the VT booster which obviously allows a bigger pressure output than the smaller VS one, pedal feel will be better than with the VS Booster/VT master combo.

Agreed. The VT booster will provide higher line pressure for the same amount of pedal effort.
 
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