Hi all. Going to install HRP pedalbox/column in the Mk1 Rocco and will be running standard Gti brakes with DS2500 pads on the front. Can anyone tell me the correct master cylinder size for the front and rear and which brand does everyone use/recommend? Do people run remote reservoirs into the engine bay or is there enough room under the dash? Thanks for any help. Adam
I was looking at two of these: https://www.rallydesign.co.uk/product_info.php?cPath=562_582_583&products_id=4046 With remote reservoirs in the bay. Will 0.625 front and rear be right with the standard brakes? Cheers
That should be about right although you'll need a bias valve for the rear. If the rear still locks up too easy then use a 0.7 rear.
Just an update on this. Got all the above fitted inc new lines and braided hose and have bedded in the new discs/pads. I now have a very firm/wooden pedal that requires a lot of effort to push, so much effort that I can’t heel and toe whilst maintaining the desired pedal pressure. I do have sparrows legs but I think the issue lies with the car not my pins! I am literally pushing it as hard as I can. I don’t mind the feel of the pedal but the effort required seems excessive. Also the bias bar is wound pretty much towards the rear as there wasn’t a lot of rear braking force on the brake rollers. Should I wind the bias forwards, will this help with the effort required or am I going to have to change the master cylinders? Might there be something else I am missing? Any help from wise heads greatly appreciated. Adam
On the run out today I was locking the rears under hard breaking so figured it must be too rear biased regardless of what the rollers say. So I have wound the bias bar more to the front not realising it was so easy to adjust. On the short trial after adjusting I know have a softer pedal with more feel and stopping power. I will take it out tomorrow for a proper run tomorrow and see if it needs further tweaking and has fixed the previous issues.
Just an update on this. After winding the bar forwards it did help with the braking ability but they still required a lot of force. I wouldn’t call the brakes confidence inspiring and the car is about 300bhp/tonne so I really do need to get this sorted. If I changed the master cylinder size would that help? I did think these were about right for the setup but the effort needed is too much. I was also looking at these: https://momentummotorparts.com/collections/mmp-wilwood-big-brake-kits/products/9-4-239mm-mmp-wilwood-slim-line-4-piston-1-38-caliper-upgrade-mk1-rabbit-jetta-cabrio-scirroco-caddy Would just upgrading the calipers help my cause? I would really appreciate any expert advice on this as I don’t want it to become expensive trial and error. Thanks