Thread: Adding extra brake vacuum capacity for increased braking

Thanks Steve. I will start at replacing the master cyl and work my way through the system. Any idea what might fit if I go down the retrofit path?

Originally Posted by roverrescue

My 1996 130 + Bleed the system, new pads, new rotors not long ago = bad brakes
your answer is:
servo assist can develop hairline cracks

Get someone to jump the pedal while you watch the booster closely. At the ridge where the master is bolted you most likely will see a crack leaking all your hard hearned vacuum to atmo.

The problem is a brand new booster will likely crack before you even get to the death road!
It seems that the manufacturers have forgotten how to make a long lasting booster,
I would look to retrofit or go the tightarse but effective option like me.

I took two hairline cracked boosters. I carefully turned the face and rolled edge out of one and then aligned it to the second booster. Glued the two pieces together with high grade Sikka.
So now there is no flex at the face. And no leaking vacuum equals good brakes.

And btw - a Canter needs more than just a booster upgrade to provide stopping power. Those things bring the suck when you want to stop!

Steve

I think I have a hairline crack in the servo unit. Was wondering if to strengthen a new servo unit it would be appropriate to cut a strengthening patch/piece out of the old servo and then Sikaflex as suggested. Not as good as rolling out as the edge but easier for me to manage and still provide some stiffness to the stress area.

I'm not sure what calipers are on your 130. I assume the front brakes have the calipers with 4 large pistons and vented rotors. I also assume the rear brakes have the same old 2 piston calipers as used with the smaller wheel base Land Rovers.

Under hard braking with an empty short wheelbase vehicle the stock rear brakes were chosen so the don't lock the rear wheels. As such they don't contribute much to overall braking.

The rear brakes could contribute much more to overall braking when there is more traction on the rear tyres, i.e. when heavily loaded and long wheel base.

If I had a 130 with its long wheel base and that weight permanently on the back, I would change the rear calipers to the ones with 4 small pistons as used on the front of a Defender 90. AFAIK Disco I and RRC fron't calipers used the same 4 small pistons.

Increasing the volume won't increase performance but it will give you a better margin of reserve if there's a failure of vacuum supply and you need to use the brakes with the engine off.

I would look at the elec pump options if you're that worried but a good service of the system will probably go a long way to improving the situation. The elec unit will need a reservoir anyway.