Another disk brake conversion......

[Glenn]

Looking through some old magazines while cleaning up here, I found this interesting vented rotor conversion for what must be early Mazda's. I have no idea what actual models but the rotor bolts up to the hub in a very similar manner to a GT. ( I don't recall now if the GT rotor is tapped for bolts, or the hub is tapped)

This conversion gives vented disks and a new caliper completes the picture. The rotor itself is about 10", similar to a GT and they claim 13" alloy wheels will still fit too.

Does anybody recognize the calipers? The ad was from 1997 by the way. I removed contact details as I doubt they are still available as a kit. Plus I don't know if they are actually compatible with GT. Offset of the hat section looks similar though.
Might be another starting point though............

[PR91]

New caliper looks Commodore.
GT rotors and hubs are clear drilled. They use bolts and nuts.

[PR91]

A conversation that uses common discs that sit over drum brake hubs along with common calipers to fit inside 13 inch wheels is currently underway too.

[Glenn]

A conversation that uses common discs that sit over drum brake hubs along with common calipers to fit inside 13 inch wheels is currently underway too.

interesting, Brett. Any more clues?

[Glenn]

New caliper looks Commodore.
GT rotors and hubs are clear drilled. They use bolts and nuts.

VL turbo and early V8 models had an alloy finned caliper but that's not it. I have a set here on my hotrod.

They have much deeper fins on top.....

what's interesting is that the earlier Commodores used a 22mm thick disk, the TP Magna uses 24mm.

[CQGT]

My Gt convertible has girling brake calipers fitted. Another modification done by previous owner/owners.
I had them overhauled about 4 years ago and the brake specialist told me they were off of an Avanti. He was probably going
by the kit that he used as Avanti is front wheel drive and are mounted forward of the axle and have 12mm threaded holes.
I picked up a set of calipers from a wrecker from a XT130 Corona. Hole centers are the same only are 12mm drilled. !0mm on GT.
Have been trawling through all the Nissan & Hyundai parts listings for a 12/10mm hollow dowel. No luck. 14mm has been
closest. Still looking.

Dave.

[dave]

On the subject of discs, I might be close to cracking a replacement rotor at minimal cost, but like any other exercise like this, it may rely on a bulk purchase.

I will keep you posted; I didn't want to post a separate thread for it until I was certain of costs and that we could even get it done....


Cheers,

Dave

[Glenn]

My Gt convertible has girling brake calipers fitted. Another modification done by previous owner/owners.
I had them overhauled about 4 years ago and the brake specialist told me they were off of an Avanti. He was probably going
by the kit that he used as Avanti is front wheel drive and are mounted forward of the axle and have 12mm threaded holes.
I picked up a set of calipers from a wrecker from a XT130 Corona. Hole centers are the same only are 12mm drilled. !0mm on GT.
Have been trawling through all the Nissan & Hyundai parts listings for a 12/10mm hollow dowel. No luck. 14mm has been
closest. Still looking.

Dave.

what is an Avanti ?

Do you mean you need an 'adapter' to sleeve the 12mm hole down to 10mm ? That could be turned up in a lathe.

Like all these conversions, one needs to recognise what is available now, relatively easily. Like in the past, we used the early Sigma stuff. Now getting very hard to get and mostly worn out anyway. I doubt DBA etc cater for new rotors these days.
The TP Magna rotors are very easy and cheap to get as there is still demand for them, from Magna owners but also a lot of conversion use this rotor. It has its problems though, wheel size for one and finding a caliper to suit 28mm rotor. From what I have here, a TP Magna caliper won't fit. However, it might be there are two types of caliper fitted to TP's.

[CQGT]

Sorry. Spelt it wrong. AVANTE. Toyota Corona.

Dave.

[Glenn]

Sorry. Spelt it wrong. AVANTE. Toyota Corona.

Dave.

thanks

The Avante seems to have 5 stud wheels so I guess the brake rotors on your conversion are off something else.
Are they solid or vented ? Do you know how thick the rotors are ?

The Corona XT130 has 4 studs though.

The brake catalog does not list any available disk brake parts for these models.


For the Australian market, there were two Corona Avante models sold between 1983 and 1987: the ST141 with a 2.0-litre 2S-C and the RT142, fitted with a 2.4-litre fuel-injected 22R-E.

[PR91]

A conversation that uses common discs that sit over drum brake hubs along with common calipers to fit inside 13 inch wheels is currently underway too.

I was privy to seeing how this conversation is coming along this morning....
Looks very nice, fits inside standard 13 inch wheels, uses commonly available parts, and will work well.
Honestly..... I'm surprised at how neat it all is and looks like it came from the factory.
I believe once developed they may be offered on a change over basis, but that's depending on its success and time will tell.

[Glenn]

A conversation that uses common discs that sit over drum brake hubs along with common calipers to fit inside 13 inch wheels is currently underway too.

I was privy to seeing how this conversation is coming along this morning....
Looks very nice, fits inside standard 13 inch wheels, uses commonly available parts, and will work well.
Honestly..... I'm surprised at how neat it all is and looks like it came from the factory.
I believe once developed they may be offered on a change over basis, but that's depending on its success and time will tell.

sounds excellent , Brett. If it's that good, it should be popular. Proviso of course that parts are easy to get.

Ref "change over" does that mean the sedan hub has to be machined though ?

[PR91]

A conversation that uses common discs that sit over drum brake hubs along with common calipers to fit inside 13 inch wheels is currently underway too.

I was privy to seeing how this conversation is coming along this morning....
Looks very nice, fits inside standard 13 inch wheels, uses commonly available parts, and will work well.
Honestly..... I'm surprised at how neat it all is and looks like it came from the factory.
I believe once developed they may be offered on a change over basis, but that's depending on its success and time will tell.

sounds excellent , Brett. If it's that good, it should be popular. Proviso of course that parts are easy to get.

Ref "change over" does that mean the sedan hub has to be machined though ?

Yes. Only slightly a couple of mm on the outside diameter I'm told so the rotor will slip straight on.
Apparently its so minor that when looking at the finished one you couldn't tell the difference to an original without direct comparison.

[PR91]

Oh, and I believe the parts were sourced from a local wrecking yard that had 4 or 5 of the same cars available, so supply shouldn't be any problem.
And new rotors are available over the counter from 2 different manufacturers as well.

[Glenn]

Oh, and I believe the parts were sourced from a local wrecking yard that had 4 or 5 of the same cars available, so supply shouldn't be any problem.
And new rotors are available over the counter from 2 different manufacturers as well.

all sounds good, can't wait to hear more........ solid or vented?

what about stud length, for alloys

should work for GT's i imagine also.

[BULLITT]

mate hurry up and tell us . we are sitting on the edge of our seats ..one of my.... to do jobs .... are the brakes on the 90 ...so would be great if local bits fit ...well done boys ...davo

[PR91]

Oh, and I believe the parts were sourced from a local wrecking yard that had 4 or 5 of the same cars available, so supply shouldn't be any problem.
And new rotors are available over the counter from 2 different manufacturers as well.

all sounds good, can't wait to hear more........ solid or vented?

what about stud length, for alloys

should work for GT's i imagine also.

Vented.
Stud length is the same as normal as the rotor just replaces the drum.
GT's will require a change to sedan drum brake hubs, and depending on the upright, might need sedan versions as well.

[PR91]

mate hurry up and tell us . we are sitting on the edge of our seats ..one of my.... to do jobs .... are the brakes on the 90 ...so would be great if local bits fit ...well done boys ...davo

No specific details will be given until it's tested and proven.
Also, if it's a changeover process, those who have put alot of time and effort into it will charge for their services, which is fair enuf too, but I velieve a 'kit' is being considered, in that the hubs are changeover, new caliper plates, all mounting hardware, hoses, etc will be supplied, and you'll be advised as to what rotor and caliper to source, so it's a proper bolt on conversion.
Only early days yet, so don't expect this in the next week tho.

[Glenn]

Oh, and I believe the parts were sourced from a local wrecking yard that had 4 or 5 of the same cars available, so supply shouldn't be any problem.
And new rotors are available over the counter from 2 different manufacturers as well.

all sounds good, can't wait to hear more........ solid or vented?

what about stud length, for alloys

should work for GT's i imagine also.

Vented.
Stud length is the same as normal as the rotor just replaces the drum.
GT's will require a change to sedan drum brake hubs, and depending on the upright, might need sedan versions as well.

I need to look at both hubs but assumed GT would be similar at the wheel mounting face anyway ?

[Glenn]

mate hurry up and tell us . we are sitting on the edge of our seats ..one of my.... to do jobs .... are the brakes on the 90 ...so would be great if local bits fit ...well done boys ...davo

No specific details will be given until it's tested and proven.
Also, if it's a changeover process, those who have put alot of time and effort into it will charge for their services, which is fair enuf too, but I velieve a 'kit' is being considered, in that the hubs are changeover, new caliper plates, all mounting hardware, hoses, etc will be supplied, and you'll be advised as to what rotor and caliper to source, so it's a proper bolt on conversion.
Only early days yet, so don't expect this in the next week tho.

my sneek peek.... looks great !