23mm M/C myth?

[sexy_gt]

i have a 2000 vts with abs. without me measuring my old 2 port m/c can anyone tell me what size it is? there is nothing stamped on or underneath it :)

reason i am asking is i have a hispec brake kit to fit to the car. hence i have bought a 23mm m/c from a club member. not the issue here.

i had a chat to gmc today about brakes and such. i mentioned that i have a 23mm 2 port from another car that will fit. gmc told me that the m/c i have bought will not make any change as the vts has a 23 as standard.

john at gmc is a great bloke and is very knowledgable. i respect his word. i was lead to believe that my car should be a 21 as standard and this 23 is an upgrade to suit my new 4pots (small 1&1/4" pistons)?

so my questions are what size is mine as standard and to those that have fitted a larger m/c have you felt a difference?

cheers for reading and replies in advance.

stew :panic:

[raunchz]

Anyone on servicebox should be able to tell you the size of mc that vts's came with - I'll log on tomorrow if no-one does it in the meantime - I'm on the iphone

[Andy_K]

One of my old vts's cam with 22 stamped on the mc iirc
I thight this was standard size.

[sexy_gt]

even if its a 1mm upgrade i will fit it. i want a lot of bite from these brakes! i did read they are 23.6?

[chinkostu]

From servicebox


4601 g0
master cylinder
diam 20,6
- w/o abs brakes

4601 f3
diam 22,2
- with abs brakes



4601 f4
master cylinder
diam 20,6
bosch. -
aluminium - p012
- w/o abs brakes

[sexy_gt]

so im looking to match those bold codes on my m/c?

looks like at worst i have a little more to come from my 23mm mc but is it exactly 23mm?

[yr51ocw]

master cylinder wont affect "bite", it will only effect pedal travel and force. By going for a larger m/c you are actually going to need to exert more force on the pedal which is going against the opposite perception of "bite" which is alot of braking force for little pedal force.

[swampy]

Those in bold will be the part number and wont feature on the parts themselves.

[sexy_gt]

master cylinder wont affect "bite", it will only effect pedal travel and force. By going for a larger m/c you are actually going to need to exert more force on the pedal which is going against the opposite perception of "bite" which is alot of braking force for little pedal force.

surely extra force will result in more bite?

if i press the pedal in x amount and get y "force" then surely if i fit a larger m/c and press the same x amount i will get more y "force"?

[Tufty]

Hello mate, let me clear this up for you, the 23mc is an upgrade to you, but not by very much. I have fitted mine with 306gti6 brakes and there is still a tiny bit of pedal travel... However, they are much more responsive, and a bit lighter (less effort resulting in faster bite) So you will have to learn brake points all over again.

Hope this helps mate

Edit, this is what i have found

[yr51ocw]

nope, afraid not. Thats not how hydraulics work.

The pair of cylinders (master, and slave in the caliper) act as a to mulitply the force (much in the same way levers do), changing the ratio of the cylinders changes the ratios of the forces (like changing the length of a lever)

Have a quick google search as I am terrible at explaining things

[sexy_gt]

its ok cheers i understand. like a quickshift throws longer one end less at the other ar the expense of a more stiff throw ;)

[yr51ocw]

yeah you got it. Dont be suckered into thinking that bigger is better. Have a think about that you really want from your brakes. Have you checked the piston area between the old and the new calipers?

I personally am going to be using a smaller than OEM m/c with my 4 pots this year as I wanted a longer, softer pedal to help modulate the braking force with more ease.

[Tufty]

So the "23mm" is that the size of the piston inside? If so, this means it should just disperse of the brake fluid quicker to the correct lines causing less travel?

[yr51ocw]

^ yes, but at the expense of more force required at the pedal to move the fluid

[sexy_gt]

im going to fit the with the standard m/c. i wont think twice about changing it if i dont like the amount of pedal travel.

after all this car gets beaten on a track and the pedal is very important!

[sexy_gt]

^ yes, but at the expense of more force required at the pedal to move the fluid

thing is your legs are very strong. i cant see that 1mm or whatever making a problem?

[Tufty]

^ yes, but at the expense of more force required at the pedal to move the fluid

To be fair though, its not going to be stupid force required? and on track you dont stamp on the brake anyway? you should ease in the brakes?

not having a go at all... Its interesting, done some research and have now learnt something.

but from what i read on a post from swampy, he was saying there is loads of pedal travel with the standard master and 4 pots.

Jason :y:

[yr51ocw]

he was saying there is loads of pedal travel with the standard master and 4 pots.

All depends on the piston size, all 4 pots are different so you need to be careful with that one.

No the difference wont be large. My main point is, bigger isnt better. And perhaps try it with a std m/c before you think you need a different one. I have done this and learnt that I need a smaller one for my car and my driving style.

[sexy_gt]

To be fair though, its not going to be stupid force required? and on track you dont stamp on the brake anyway? you should ease in the brakes?

not having a go at all... Its interesting, done some research and have now learnt something.

but from what i read on a post from swampy, he was saying there is loads of pedal travel with the standard master and 4 pots.

Jason :y:

jase im supprised i havnt snaped my brake pedal some times.

i hammer them on. when you have that much confidence and your car is set up well you will!

[adamskiTNR]

Once my pedal box is done i'm going to have a mission experimenting with different mc sizes. and maybe having to make different pedals to get the braking right. what with no servo assistance

[Tufty]

jase im supprised i havnt snaped my brake pedal some times.

i hammer them on. when you have that much confidence and your car is set up well you will!

Haha, dam man! You know best i guess, done so many track days!!

Il ease into the brakes at first lmao!

I am a bit of a speed freak, so once i get going, i do like to find the ultimate level! and do try to not cross it.

http://img25.imageshack.us/img25/9166/45773825.jpg (http://img25.imageshack.us/i/45773825.jpg/)

[blackie_2k5]

ive got brembo 4 pots on oe vtr m/c get about an inch travel, still plenty to go, i can lock the wheels well before i run out of leverage, and i mean well, takes a week or so to get used to but i actually prefer it now ive had them a while

[Sophia_Bush]

had loads of travel just adjusted the brake bar

[Tufty]

had loads of travel just adjusted the brake bar

how do you adjust the brake bar mate?

[sexy_gt]

had loads of travel just adjusted the brake bar

i have asked about it bedfore and heard is was best left alone?

[raunchz]

had loads of travel just adjusted the brake bar

You can only really take out any 'play' in the pedal - tightening it any further will start to put brakes 'on'/bind

[willsy]

So many components playing a part in braking.

Does anyone know what if any the differences are with varience in Servo aswel?

When i had the 6 pots on the Saxo with the 23.6mm M/C I was still using the original 1.0 smaller servo. Absolutely loved the way the brakes felt but would/could i have benefitted with the larger Servo also - just out of interest

Guess ive just opened up another bit for debate with the Servo anyway

[sexy_gt]

oh dear... i have removed m/c and it does have a small 23 on it. not stamped in but in the cast moulding underneath.

[adamskiTNR]

4pots and six pots alike often don't need any more power applied to them. as most apply pressure to each of the pistons sequentially to give smoother braking and preventing sudden lock up. So a bigger servo would not be needed

[sexy_gt]

its not the number of pots tho its the volume of fluid thats required. 4 small pots could require less fluid than a large single for example.

[sexy_gt]

http://img.photobucket.com/albums/v212/sexy_gt/saxo%20vts/23mastercylinder.jpg

[sexy_gt]

can we agree that the above was fitted as standard?

[adamskiTNR]

yeah, 4 pots and 6 pots each piston is incy wincy

[qrty]

http://img.photobucket.com/albums/v212/sexy_gt/saxo%20vts/23mastercylinder.jpg

Maybe they had them knocking about in the facotry at the time lol!

When I have checked on the Citroen Portal before the previous sizes posted for VTS have always come up!

When I took mine off it had 22 stamped on the bottom similar to above picture and I have replaced it with a 23mm! The only difference was your 23 has a sort of oval shape base where it bolts on! Mine was round with two square tabs where the bolts go through! :wacko:

[sexy_gt]

could you tell difference between 22 and 23?

[sexy_gt]

bump :)

[jonathon5]

Lucky, which side do the pipes come off ?

[sexy_gt]

passenger side outlets

[blackie_2k5]

my vtr had 22 standard, could well have been uprated or used while waiting on a shipment of 22's

or possibley replaced as a spare without even knowing...

[sexy_gt]

fitted my hispec brakes today 1 1/4" piston type. very happy with pedal and bite.

[Mikol]

No saxo's had 23.8mm Master Cylinders as standard. End of discussion.

22.2mm -> VTS (abs)
20.6mm -> 3 stud, VTR, Furio
19mm -> 1.1, 1.4 with solid discs

As recycled through everyone else's posts - it's your call. Bigger bore = higher 'bite', less travel to lock, firmer feel, however less graduation and more leg effort required.

[MikeyW]

Rather than starting a new thread, does anyone know if I need a 4 port or 2 port 23mm MC for my 2001 VTR, non ABS (obviously).

[sexy_gt]

if it has 2 or 4 port fit the same again.

[sexy_gt]

No saxo's had 23.8mm Master Cylinders as standard. End of discussion.

22.2mm -> VTS (abs)
20.6mm -> 3 stud, VTR, Furio
19mm -> 1.1, 1.4 with solid discs

As recycled through everyone else's posts - it's your call. Bigger bore = higher 'bite', less travel to lock, firmer feel, however less graduation and more leg effort required.

not saying i have 23.8 im saying look at that picture it clearly has 23 on it :)

brakes feel great with it.

[chinkostu]

Rather than starting a new thread, does anyone know if I need a 4 port or 2 port 23mm MC for my 2001 VTR, non ABS (obviously).

abs - 2 port
otherwise 4 port