[Mgs] Brake shoes

[Barney Gaylord]

Keep the shoes properly adjusted, and use slightly larger modern 
radial tires.  155-80-15 would be close to the orginal 5.60-15 bias 
ply tires for size.  165-80-15 is closest to original diameter to 
make the speedometer and odometer most accurate.  165 is also more 
common and may even be cheaper than 155, and is the largert tire 
recomended for use on 4" wide rims.  That said, a lot of people have 
installed 185-70-15 tires on 4" or 4-1/2" rims with pretty good 
results.  Not real pretty on the narrow rims, but they work.

Keep the shock absorber fluid topped up so the wheels and tires don't 
bounce while on the brakes (especially in corners).  More rigid 
wheels also help reduce bounce and wobble (especially on bumps in 
corners).  That is, 60-spoke wire wheels can improve braking, believe 
it or not.  72-spoke as well (although they look somewhat "busy" on an MGA).

Most alloy wheels will also be stiffer than any factory wheels (wire 
or steel), so as strange as the odd alloy wheels may look on the MGA, 
they can and do brake and handle better (especially on bumpy surfaces).

The ultimate limit for braking is grip where the rubber meets the 
road.  When you can step hard on the pedal and lock up all four 
wheels at any speed, it doesn't get any better than that.  Youi could 
install soft rubber race tires that grip better and wear out a lot faster.

You could install a power brake boster to reduce pedal effort, but do 
not expect it to reduce braking distance at all.

One thing that definitely will not help braking is to screw up the 
front to rear brake force bias.  Installing larger bore slave 
cylinders on the front will only make the front tires lock up early 
before rear tires have developed full force, which would result in 
longer stopping distance.  Installing larger bore slave cylinders on 
the rear only will make the rear tires lock up before the front ones 
have developed full force, also making longer stopping distance.

Installing larger bore slave cylinders all around can reduce pedal 
force, similar to installing a power booster, but also makes for 
longer pedal travel.  You can get similar results by sleeving the 
master cylinder to smaller bore size.  None of that wil increase grip 
of tires on road or reduce stopping distance.

Disc brakes can reduce brake fade (which most people will never 
encounter unless racing).  By the nature of all around good brakes, 
disc brakes cannot be any more powerful than the drum brakes, as that 
would screw up front to rear biase and increase stopping distance.

The factory got it pretty close to right from the beginning, not from 
any magic, more from decades of practical experience, so that's kind 
of hard to beat.

Barney


At 04:06 PM 6/24/2021, Thomas Gunderson wrote:
>How can I improve the standard brakes?
>Tom Gunderson 1957 MGA 1500 rst
>....

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