Guest sam1990rhodes Posted January 18, 2017 Hi All, Have fitted some Brembo's to my 2.0 16v (now 20vt), the brakes feels spongy now, no where near as good as I expected Brembos to be. My suspicion is that the Brake Servo or Master Cylinder isn't pushing enough fluid to the callipers, but has anyone got any knowledge/experience of this? cheers. Quote Share this post Link to post Share on other sites
g0ldf1ng3r 13 Posted January 18, 2017 Hi All, Have fitted some Brembo's to my 2.0 16v (now 20vt), the brakes feels spongy now, no where near as good as I expected Brembos to be. My suspicion is that the Brake Servo or Master Cylinder isn't pushing enough fluid to the callipers, but has anyone got any knowledge/experience of this? cheers. unsure for brembo's specifically i do recall dragon saying that hi HiSpec 4 pots gave a spongier feel than standard but believe they were still very good at stopping i hope so as i have just had some Billet 4's fitted Quote Share this post Link to post Share on other sites
VEEDUBBED 0 Posted January 18, 2017 Also depends on the master cylinder diameter and if you have abs. Have a look using the search, it's been covered before recently. Quote Share this post Link to post Share on other sites
swiftkid 1 Posted January 18, 2017 Have you upgraded to VR6 master cylinder or are you still on 16v one? If not my moneys on master cylinder, I've seen a few discussions in the past. I've got a set of wilwoods to go on with big pistons so I'm likely to have the same issue. Quote Share this post Link to post Share on other sites
mic_VR 3 Posted January 18, 2017 Yep, this is a common problem with the use of 4-pots. The master cylinder would ideally be upgraded at the same time. Mine feel soft on the initial push of the pedal but keep going and they're amazing. You learn to drive around it after all while... which is interesting when you drive a modern car for the first time and it feels like you've stamped on the brakes! :lol: Quote Share this post Link to post Share on other sites
g0ldf1ng3r 13 Posted January 18, 2017 Yep, this is a common problem with the use of 4-pots. The master cylinder would ideally be upgraded at the same time. Mine feel soft on the initial push of the pedal but keep going and they're amazing. You learn to drive around it after all while... which is interesting when you drive a modern car for the first time and it feels like you've stamped on the brakes! :lol: that is pretty much what dragon said Mic cant wait to get my VR back & give the Billet's a try :) Quote Share this post Link to post Share on other sites
mic_VR 3 Posted January 18, 2017 You not got that back yet?!?! Quote Share this post Link to post Share on other sites
Guest sam1990rhodes Posted January 18, 2017 Cheers Guys, will be on the look out for a VR master cylinder then. IIRC they're shorter than the 16v ones? could kill two birds with one stone as the 20vt engine sits too close to comfort to the valver MC. Quote Share this post Link to post Share on other sites
Guest sam1990rhodes Posted January 18, 2017 Also depends on the master cylinder diameter and if you have abs. Have a look using the search, it's been covered before recently. I have ABS, how is this going to cause an issue? Quote Share this post Link to post Share on other sites
g0ldf1ng3r 13 Posted January 18, 2017 You not got that back yet?!?! ha ha no my mechanic has been ill & it was christmas 3 days after they arrived the brakes are fitted, as per pic in my build thread, but the sill hadnt been welded i have the valver to use in place so am pottering in that. got 34.5mpg on the MFA on my 14 mile journey to work this morning, not bad for an old bird :D Quote Share this post Link to post Share on other sites
Dox 22 Posted January 18, 2017 I have ABS, how is this going to cause an issue? If you trigger the ABS into fault you'll find a reduction in pedal travel and a less spongy feel to the pedal too. New pads can also give a spongy feel to until they've bedded in Quote Share this post Link to post Share on other sites
Rado87 10 Posted January 18, 2017 I had similar issues on my VR when I swapped all the calipers, discs, pads and fluid change. There are two bleed nipples on the ABS pump and one on the master cylinder too. Sent from my iPhone using Tapatalk Quote Share this post Link to post Share on other sites
Rado87 10 Posted January 18, 2017 Once o bled these out the brakes were spot on. I'm sure you probably knew this but thought I'd mention it! Sent from my iPhone using Tapatalk Quote Share this post Link to post Share on other sites
VEEDUBBED 0 Posted January 18, 2017 I didn't say it would cause an issue if you had abs, I meant that it should already have the bigger master cylinder fitted already, opposed to the smaller non abs version pump. Sounds like there's still air in the calipers. Quote Share this post Link to post Share on other sites
Guest sam1990rhodes Posted January 18, 2017 I didn't say it would cause an issue if you had abs, I meant that it should already have the bigger master cylinder fitted already, opposed to the smaller non abs version pump. Sounds like there's still air in the calipers. Ok mate cheers, ill try a rebleed. Quote Share this post Link to post Share on other sites
VAG-hag 0 Posted January 18, 2017 Did you change your lines to braided? Mine feel a little soft compared to a modern car but really no worse than std. Quote Share this post Link to post Share on other sites
marks2 0 Posted January 18, 2017 (edited) I'm not sure which brakes you went from / to but if you take the G60 caliper it uses a 54mm piston. If we assume 0.5mm of piston travel then the each piston displaces 4580 mm cubed or 9161 for a pair. The Porsche 996 caliper (996.351.425) uses a pair of 40 + 36mm pistons. Using the same 0.5mm of piston travel all 8 pistons displace 18,196mm cubed which is slightly less than double the G60 caliper. Assuming of course my math is correct. Now I know this theory is flawed as the G60 is a floating caliper and the Porsche a fixed but it goes some way to explain why the pedal travel is increased Echoing the previous posts whilst I would expect more travel your brakes should not be spongy. I too think you have air in the system. Edited January 18, 2017 by marks2 Quote Share this post Link to post Share on other sites
Guest sam1990rhodes Posted January 18, 2017 Did you change your lines to braided? Mine feel a little soft compared to a modern car but really no worse than std. Braided hoses front and back and lines all replaced with copper. Quote Share this post Link to post Share on other sites
Guest sam1990rhodes Posted January 18, 2017 Thanks everyone, ill bleed the system again and report back. Quote Share this post Link to post Share on other sites
VEEDUBBED 0 Posted January 18, 2017 Sam, when you do re-bleed the System, try and use a pump Like the Sealey Version that has a pump handle that pressurizes its own bottle filled with brake fluid. I try not to use the two man method of pumping the brake pedal to the floor, there's always the risk of buggering the internal seals on the pump that's 20+ years old and has had the internal seals working only a few mm's of travel during all those years.. Not saying it WILL happen but you never know mate.. I Quote Share this post Link to post Share on other sites
Sleprock01 10 Posted April 6, 2017 Hi everyone Sent from my SM-G930V using Tapatalk Quote Share this post Link to post Share on other sites
Guest sam1990rhodes Posted April 6, 2017 Hi :) Quote Share this post Link to post Share on other sites
mandipvirdi 10 Posted August 2, 2017 Hi all, I have the g60 front brake upgrade, however my brakes are also a bit weird. They sometimes brake with the pedal high, and then a second or so after its as if the pressure is released and then i have my foot quite far down to make the brakes work. The car stops and stops very well. Reckon this will just need bleeding again? Quote Share this post Link to post Share on other sites
Dox 22 Posted August 2, 2017 Rear compensator seized? Quote Share this post Link to post Share on other sites
mandipvirdi 10 Posted August 2, 2017 Sorry for being a numpty here, but what does that do? Quote Share this post Link to post Share on other sites
