Rear brakes upgrade to AP - THEORETICAL ONLY

I don't have ABS, but I do have an adjustable bias valve fitted into the rear brake line...

Some more info for you.

http://www.the-t-bar.com/forum/9-mgf-tf-pitstop/51924-start-of-ap-rear-brake-conversion

This is an interesting subject, I'm keen to hear your findings - theoretical or otherwise!

It's something that I will get round to one day, but I have been concentrating on the vent.

Once it is on the road I will be starting the rear end refurb and will be incorporating this.

Not sure if the rear hubs are the same, but there was very little alteration needed to fit the callipers.

Thanks for that info Clive. I'd forgotten that you had approached this subject earlier.
The holes in the hub I found were too small and spaced just too far apart. I enlarged them to fit and had to remove a very small amount of the hub casting to get the callipers to fit correctly. As you found, the callipers are then aligned perfectly on the 304mm discs. The discs are a straight swap of course. :yesnod:

Same size on front and back is wrong. i won't want a ride in it

OK, we'll try to remember.

The brake proportioning valve is there to compensate.

stephenj wrote: Same size on front and back is wrong. i won't want a ride in it

Non AP cars have 240 front and rear......

Plus David has the bias valve to compensate for any potential lock up.

As for the separate handbrake, Volvo has used a separate mini shoe arrangement for years with no issues and handbrake-less disc calipers!

If the 304 all round arrangement can avoid the brake fade from the crappy ( Rover 800 parts bin ) rear 240 setup then it has to be a step forward.

I understand all the reservations about this leap into the unknown, but please be assured that I am not in the business of dangerous modifications. Many cars have a separate handbrake system. My Nissan has disc brakes all around with a drum handbrake for instance and as Adam points out the original MGF brakes are 240mm discs all around with the same size brake pads.

Additionally the proportioning valve allows me to set the brake balance up to get near perfect front/rear split. I can have as little as 20% of original brake pressure going to the rear callipers. The final setup will be carefully adjusted off public roads, actually on a disused airfield with a huge area for compensating for any errors.

MGZT/Rover 75 use a BMW designed rear brake with discs for stopping and a mini drum inside for handbrake.

Well, I finally got around to fitting the modified hubs with the 304 discs and AP 4 pots to the rear. Bled it all up, turned the brake bias valve to minimum rear pressure and ventured carefully out onto the roads.

Well the doom mongers were right, I've actually injured myself. :omg:

I think I have suffered haemorrhages to both my eyeballs. Caused by the g-forces of the utterly awesome braking ability of the car. :bust:

O.M.G. I need to try them in the wet to set up the bias valve properly so am erring currently on the side of caution. The fronts will still lock up first but adjusting the valve to allow a touch more pressure to the rears means that it only locks up at the front under hard braking. Which feels a bit like driving into a tree!

I still haven't fitted the handbrake callipers. I need to sort out some brackets and hopefully re-route the handbrake cables so that they come out at the front of the hub rather than the rear.
Does anyone know the route where the cables run from the firewall to the hubs? edit Found the route.