MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGB Technical - Big Brake Kit - where from

Hi all, I am converting my MGB GT to Ford Zetec power. It's been approved by the local SVA equivalent here in Norway with the demand that the brakes are upgraded to or beyond the original V8 brakes, so I thought I'd fit a big brake kit. What's the best place to get such a kit as they all seem to supply different contents in their kits? Moss? Brown & Gammons?
N.C. Nielsen

Try www.britishV8.org there several articles/advertisers who can supply the sort of braking system you are after 0just lay in a big stock of tyres
Andy
ap lestocq

Take a look at Bill Guzman (of Classic Conversions in California) kit:

http://www.classicconversionseng.com/

Another option is that of Jim Hall's kit (of MG Five Speed in Florida):

http://www.mgfivespeed.com/

Rick Ingram

You can up the brakes all you like but it isn't going to stop you sooner or better unless you also change the tyre width and/or compound. Brake effectiveness i.e. retardation is controlled by the tyre contact patch with the road, as you should *always* be able to lock the front wheels with steadily increasing pedal pressure. Increasing just the fronts can also result in *reduced* overall braking performance if you end up with lower hydraulic pressures, as that will reduce braking effort from the rear.
Paul Hunt

http://www.zeus.uk.com/calipers.php

I have these and they do stop you, very quickly

K Harris

Hi,

You can also go for Austin Princess 4 pot brake calipers. You can search for them on e-bay, buy new or search at junkyard. You will have to use longer bolts (same as on TR 6, 4 pcs) new flexi hose (metric on caliper side and imperial on standard B pipeline), you will have to "shave" a bit back plate and install B V8 discs (I use cross drilled). Since Princess use two oil feeds you will have to bridge them with short pipe, or make internal connection between chambers.

Alternatively you can add spacers and use Peugeot 505 vented discs. Spacers are same as are used on Escort applications, so you can buy them from Ford specialists (www.burtonpower.com).



toni

Paul I think we understand the concept of having bigger wheels in order to fit bigger disks which substantially increase the braking surface area. But fitting those brake kits mentioned before your statement does in fact improve braking. I dont think I have to go into the 4 pot vs. one. It seems like your saying forget putting four pots on, and even vented disks. It is a great saftey improvement over stock brakes. I dont see how you can argue against it.
James

Hi all, I think I need to give some more info on my car; It's a 67 GT mkI which I am performing a Ford ZETEC engine swap into. That should give me approx 160BHP. Engine swaps and other changes made to cars here in Norway are covered by VERY strict rules. NAd it is because of a demand that I upgrade the brakes to pass my engine swap that I need the bigger brakes.

I run 185/65/15 Pirelli P6000 tires so have about 20mm wider contact patch than original. I agree that in reality the ability to lockk the brakes in all conditions is all that really is need, but the Norwegian equivalent to the SVA has ruled for bigger brakes (alteast V8 dimensions).

I have been in touch with Jim Hall at the Five pSpeed Company but every time there's talk of shipping costs he goes silent/stops replying to my e-mails.

I've already bougt Bill Guzmans 4 link kit, so I know he'll ship, but I thought I'd see what else there is out there. Moss' kit looks really good.

Do remember that the UK£ is 9,5 norwegian kroner and that the US$ is 7 norwegian kroner, so finding a decent priced kit int he UK looks like the way to go.

NAny more leads, maybe to someone that do moss parts and is willing to discount?

Thanks to all that have replayed
N.C. Nielsen

Bigger discs and *wheels* also won't make any difference to how well you stop, it is the *tyres* that make the difference. Fitting bigger brakes i.e. larger surface area simply means that you can lock the wheels with a lower pedal pressure. All very well and good, but that reduces braking force at the rear at the same time (unless you increase the size of the rear slave cylinders as well) which will *reduce* overall braking effect.
Paul Hunt

Hi Paul, I agree, but unfortnatly the SVA-man has ruled for bigger brakes than stock, so bigger brakes are what I need regardless of the original brakes capacity.
N.c.nielsen

Rules is rules!

V8 brakes are thicker than 'normal' brakes, but the diameter is the same.

EBC do a kit with thicker disks using standard calipers (need a bit of filing in my experience) and thinner pads - V8 swept area I think. Such a kit should be in the spirit of the rules?

Otherwise, Moss UK has kits but they are monstrously expensive.

BTW, it is the effective diameter of the disk brake that determines the braking torque - not the size of the pads or the thickness of the disks.

Neil
Neil

There is a kit offered by http://www.frontlinecostello.com
Just have a look and you will find adequate brakes at a very reasonable price, compared to some strange offers on the web.

BTW, if yo go for the light 2 litre Zetec the normal brakes should be adequate and those used in a allmost stock V8 even more.
On my roadster, i stayed with the stock setup although it was dyno tested at 122 rwhp (B-series engine). The V8 was tested at 188 rwhp and the stock V8 setup shows it's limits at this stage!

Hope this helps

Ralph

Ralph

Agreed thickness of the discs is irrelevant, except in as far as fading goes. But all other factors being equal more pad surface area will offer greater retardation for a given pedal pressure than smaller.
Paul Hunt

Paul,

I don't agree. Brake torque is a function only of force, diameter and friction coefficient. Size is not a factor, other than as regards heat and wear.

Neil
Neil

I have a pair of new not recon princess four pot calipers surplus to requirements. Complete with fast road type pads they will operate effectively with V8 discs either std or grooved types. If these are of interest to you E mail me direct. I hope this post does not infringe on site rules. I use this setup on my own supercharged BGT.

Jim
jim soutar

Neil - you can't be saying that no matter how large the pad area is, or how small, the retardation effect is the same?
Paul Hunt

Paul,
I am. The friction force between two surfaces is the product of the applied force and the coefficient of friction. The brake torque is the product of the friction force and the effective diameter. Racing brakes often have large diameter disks, even rings, using only the outer edge.
Neil
Neil

This thread was discussed between 23/01/2009 and 29/01/2009

MG MGB Technical index

This thread is from the archives. Join the live MG MGB Technical BBS now