Disc Brakes

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DirtyShirt
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Disc Brakes

Post by DirtyShirt »

As of now I have the marina disc brake setup on my '64 van. I would like to convert to the MG Midget disc brake, is this even possible without major modifications?

Dave
bmcecosse
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Re: Disc Brakes

Post by bmcecosse »

The Spridget brakes fit straight on - provided you have the '?' shaped bracket for the caliper mounting?
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twincamman
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Re: Disc Brakes

Post by twincamman »

Why would you want to change to smaller discs?
bmcecosse
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Re: Disc Brakes

Post by bmcecosse »

Spridget hubs have the correct 4" PCD for Minor wheels ........
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deano69
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Re: Disc Brakes

Post by deano69 »

How effective/suitable would these disc brakes be for a 'warmed up' 1098 engine? Wolseley 1500 front brakes are difficult to find and becoming expensive to buy.....
DirtyShirt
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Re: Disc Brakes

Post by DirtyShirt »

The reason for the change is the 4" bolt pattern but not for the morris wheels. I have a set of Vega GT wheels that I was going to put on my Bugeye but they were too wide. The GT wheels fit perfect on the Morris Van.
As for the MG brakes working any better than the marina brakes, this is not a UPS race truck, this is just my everyday driver with a 1275 and a 3.9 rear.

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bmcecosse
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Re: Disc Brakes

Post by bmcecosse »

They will be fine - but you need the brackets.
I think this is it.........[frame]Image[/frame]
Although that may be for another caliper - can't remember now - but the concept is the same.
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charlie_morris_minor
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Re: Disc Brakes

Post by charlie_morris_minor »

have you spoken to esm? they might be able to modify the marina hub to the moggy stud pattern.. might be cheaper than swaping over to midget disc setup?
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twincamman
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Re: Disc Brakes

Post by twincamman »

charlie_morris_minor wrote:have you spoken to esm? they might be able to modify the marina hub to the moggy stud pattern.. might be cheaper than swaping over to midget disc setup?
That would be a good plan. The Marina discs are really good, I've managed to stop a Minor from a three-digit speed (on a private test track :D ) without any drama. Don't forget that these are essentially the same brakes as the Dolly sprint, which is a fair bit heavier and faster than the Minor.
67-2door
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Re: Disc Brakes

Post by 67-2door »

If you have a servo fitted it may be ok, but I had a midget disc conversion on my minor without a servo and it was dreadful. Replaced it with standard 8" drums and they're an improvement!

bmcecosse
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Re: Disc Brakes

Post by bmcecosse »

Yes - nothing wrong with 8" drums and of course the 9" version are fantastic! I believe the Spridget discs can be easily uprated by using larger calipers (ex Metro perhaps?). But for sane road motoring - 8" drums are fine.
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IslipMinor
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Re: Disc Brakes

Post by IslipMinor »

The 'J' bracket picture is the right one for Spridget calipers - it is one I posted a while ago!!

Metro 4-pot calipers have the same total piston area as the standard Spridget calipers, so no benefit to pedal pressure, but they do spread the load across the pad more evenly, which is what they are designed to do.

I would definitely look to keep the Marina set-up and change the PCD to 4". The Midget conversion does need a servo to get a reasonable pedal pressure, especially if you then use a harder pad as well.

I have the 'J' bracket drawings for both the Spridget caliper and the Metro caliper - they are not interchangeable. Can email if you are interested.
Richard


bmcecosse
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Re: Disc Brakes

Post by bmcecosse »

I think the Metro uses larger pads though - which is what counts for braking performance - the Spridget ones being miniscule. Can you post up the bracket drawing for the Metro caliper Richard ? Is the pitch much different ?
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IslipMinor
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Re: Disc Brakes

Post by IslipMinor »

The first drawing is for the Metro 4-pot caliper, with either Midget solid discs or Metro solid or vented discs, the second one is for the Midget caliper with Midget solid discs. The mounting centres for the calipers are 3.25" for Midget and 3.5" for Metro.

The Metro bracket is the one I have used since 1998, initially with the Metro 4-pot caliper and Midget solid discs, and for the last 2 years with Metro vented calipers. To use Metro discs requires machining of the disc to fit the Midget hub and, if using the vented disc, machining of the Midget hub as well to give extra clearance for the wider, vented caliper.

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bmcecosse
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Re: Disc Brakes

Post by bmcecosse »

Excellent! Filed away for future reference - although I am unlikely to use these - thanks Richard!
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chrisryder
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Re: Disc Brakes

Post by chrisryder »

Thinking of doing this mod on my minor. Those drawings from Islip are very helpfull!

i can't quite visualize how it mounts though. anybody got a picture of the bracket in place?

please and thankyou :)
bmcecosse
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Re: Disc Brakes

Post by bmcecosse »

The bracket picks-up 3 of the 4 holes on the kingpin assembly - leaving two for the caliper to bolt on. In theory you could just make a simple bracket only picking up two holes on the kingpin - but that 3rd hole on the ? shape will give extra security/rigidity. I would make them good and thick......but of course the caliper must be centred nicely on the disc.
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chrisryder
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Re: Disc Brakes

Post by chrisryder »

oh i see it now, fresh eyes and it was obvious! it says 10mm thick on the drawing. i imagine that is sufficient for stength and centering the caliper.
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