Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Brakes

Well done griffo! There is no other logical explanation but to blame the MOT testing. A 30% difference would have shot Grumpy2 right off the road!
After confirmation with another tester, a warning to the MOT would be a kindness to the first tester and his clientele. I would not mention anything, at
any point, to the second tester.

PADS,

There has been two manufactures who made calipers used on Morgan trads since June 1993, AP Lockheed and then Caparo after 2006. The
calipers look different but function identically. They both have a minor problem (aside from being much heavier than necessary), namely the MMC
pads do not fit well. Caparo was upset about that when I visited them and they examined my car. (At the time, we were experimenting to see what
it takes to change a pre-June 1993 (Girling) front braking system to a post-June 1993 (Lockheed/Caparo.

Their engineers immediately noticed an edge had developed on the original MMC pads. It upset them and they immediately called the MMC purchasing
contact but nothing resulted. I later spoke with MMC service and two of the savvier UK dealers. They chamfer these pads as a matter of course.

I have tried all sorts of pads on my trads. Testing and tweaking Morgans is a fun hobby for me. Among these pads, I also tried racing pads.The 3-4 of
these I tried from the UK and the US, are not to my taste. They are not much sense on a road car as they are noisy and brutal on discs. The best
all-round pads I have found are from the USA, a recommendation 30 years from John Sheally II (though no one is definitive on everything).
Porterfields, their R4-S compound. Merely bed them in properly. So few do that and it
matters. Only takes a few minutes. After the first shocked pleasure first using them, I sent Porterfield them rear shoes to strip, and refurbish in the same
compound. I brake much better and pads/shows have proven kind to discs/drums. One thing. Porterfield is not overly bright (or werent' the ;ast time I dealt
with them 20 years ago. You are safest to send them your old pads and shoes. It is also much cheaper. If you have no old parts or are reluctant to be
without brakes, ask your Morgan dealer to save you the last old set he removed.

Google it. Porterfield R4-S Review. They perfectly suit the best use of a trad.

Lorne

I had a long conversation with Cain about the best pads/ shoes for my 2009 4/4 (Caparo) and he said that for a road car, by far the best was Pagid. I can confirm they have excellent all round performance and are less sensitive to temperature, good when cold and they don't fade when worked hard, when others would.
Unless there is something badly wrong with one of the calipers, a 30% discrepancy seems unlikely to me.
Occam's razor says it will pads and/or hydraulics.

Certainly true on a rolling road given a Mog with the power of a Roadster.

I take all the above points as sound individually but there’s a contradiction when taken as a whole.

I can’t remember the figures but for the sake of clarity I’ll provide estimates. Front left 200, front right 260, rear left 200, rear right 200. Indicating a weakness in the front left calipers yet the car brakes in a straight line when the brakes are applied either gently or with force.

Contrast that with the results from yesterday on my Z4 which were front left 258, front right 265, rear left 198, rear right 206.

The contradiction is the Morgan and Z4 both pull up straight and true, the front results show a variance from balanced only with the Morgan.

Ps. The tester is long established and well respected in our village, the garage had been testing cars with the correct up to date kit for years and years.

Could this be due to the Morgan being a very light car?
It would be interesting to see if you got the same results if you had someone sitting in the passengers seat.

Hope you find the problem

If the brake system on the car is functioning correctly - this would be my bet. A degree of roller slippage.

12+ stone of tester sitting on one side will have an effect, add in the variable grip of the roller texture / cleanliness, and tyre pressures must be bang on equal or your contact patch is different, were the tyres wet ? or the rollers wet from previous vehicle test ?

Remember, when they test the brakes it's the test rollers actually driving the wheels, so lots of potential variables on the contact patch

My 4/4 is so light that it jumped out of the roller during the front brake test... on the first attempt, when the MOT employee pressed too hard and too fast. I also think it's better to go somewhere else and have a passenger with you during the brake test.

Yeah, mine too. Now they get two blokes in it to test. The previous garage I used to take it to had the old plate system, and the 4/4's track was too narrow to fit on the plates properly so they used to road test it with an old style Tapley inertial meter.

Never had a problem with my CRZZ6 tyres that are super sticky.