Princess 4 pot calipers

[amalgamated users from prior forum]

Message originally posted by: Lee
I have come accross a pair of Princess 4 pot calipers and discs.Has any one had an experiance of fitting these to a Marina based roadster. If so what was involved in fitting these.
Thanks
Lee

[gaddbrose]

Re: Princess 4 pot calipers

Hi Lee I have fitted the 4 pot calipers to a Berlinetta, its a straight fit with no mods and some improvement but I've never heard of them fitted to a roadster. Good luck if you can..

[jon_cox]

Re: Princess 4 pot calipers

Hi Lee,
These are a common fit for marina's. If you read the owners club forum there is alot of advice. But to summarise: The mounting holes are for metric bolts and therefore the marina bolts are too small so the caliper can "waggle". This is overcome by using the princess bolts and retapping the marina holes in the upright. Alternatively you can make or buy inserts to convert the diameter. HiSpec brakes sell them. Also, they are too big to fit under 13" wheels - this should not affect you with your lovely new ones. You must have the larger diameter master cylinder 0.75 NOT the earlier 0.7 as the 4 pot design requires the movement of more fluid resulting in a longer pedal travel. The marina disc is too small diameter wise so you will suffer pad overlap ie. a small amount of the brake pad is not in contact with the disc. This will need to be looked at regularly so as not to effect braking performance. The pads will also tend to wear at a slight angle due to the disproportioned pressure.
Don't forget that the extra braking power will change the balance front to back and generate more heat.
Must be time for the brake bias bar and twin master cylinder conversion. Check this out for a bolt on solution http://www.compbrake.co.uk/brake_p4.htm
Can even keep the servo with this idea.
Hope this helps

[amalgamated users from prior forum]

Re: Princess 4 pot calipers

Message originally posted by: Lee
Jon
Thanks for the advice I think I may come up with a few problems...1, I use a single master cylinder from a MK1 van and pedal box as there was no room for a servo with the carbs and I use a remote servo. 2,It is only single circuit not dual.

[jon_cox]

Re: Princess 4 pot calipers

Lee,
1. Single circuit no problem. Use a link pipe from one inlet to the opposite inlets bleed nipple. This is standard practice. You can also use a T piece but this requires 2 flexible hoses which is the expensive option.
2. If you have a standard girling fit master cylinder then this can be replaced with a larger capacity one. Compbrake are the cheapest I have found.