Corona Drums to Discs

[Mlaser]

Just after some advice. Buying a corona, does a 13sec qtr and its running drums, obviously not cool. Anyone have any ideas what would suit for reasonable dollars.

[Jim]

you might need to provide a bit more info than that..
what model and year of corona? what was the original engine? whats in it now?

is it the rear drums you want to replace? the first shovel nose corona had drums all round, but all the others were front disc.

the st141 and RT141 Avanté had disc brake rear end, so you'd need the avanté rear discs, calipers, backing plate, hand brake shoes (I think they are an in-the-disc hand brake mechanism on these?? Steve? :p) and the master cylinder, as the disc/drum master has a compensating valve in it, and can cause the rear discs to drag if you dont remove it.

[Mlaser]

its a 1975 corona, all drums

[Jim]

what diff? engine? you really need to give a bit more info if you can. the '75 corona is a double wishbone front end from memory...

[8>Darren<8]

Secoh,

You seem to know a lot about the Corona disk brakes, can you try to answer a question for me?

I picked up a set of rear disk backing plates, calipers etc off an ST141 with a live rear end. It all bolts up to my Celica diff with only one problem, the axles end up with about 5mm of end float because of the thicker alloy backing plate on the disk setup. Do you know how this is overcome on the corona?

I thought the outer race may have been thicker on the disk brake corona but the wheel bearings listed for both the ST141 and the RA40 are the same. I'm guessing they either must have used a spacer or the disk brake diff has a shallower bearing recess... any idea's??

Darren.

[hakosuka]

Certain model shovel nose Coronas did had factory front discs - Tte 1600S sedan and hardtop, which was sold in OZ and the 1600 GT5 hardtop (also sold here but in really tiny numbers).
They had a twin piston Dunlop or Girling system, and the caliper was the same as that used on the Jaguar E Type.

The first Coronas - all locally assembled - of the next shape (around 1970) had drums in OZ - naturally high spec Jap models had discs available, and discs were available later on this model, before the 1974 2000 model which had front discs standard for the Oz market at least

[Jim]

What Hakosuka said :p


CressidaV8...Ummm...*scratching his head* I havent come across that myself, My first guess would be that the rear wheel bearings were of different thickness but it seems you have already checked that.

Most toyota rear live beam axles have a machined step to locate the backing plate, this is probably deeper for the rear disc backing plate due to it's additional thickness from being made of aluminium, compared to the pressed steel drum brake backing plate. this is probably the problem.

I'd suggest consulting with an engineer about having spacers made for the bearing, unfortunately I suspect that the spacers will need to be between the bearing and axle flange, which'll mean taking the rear wheel bearings off and replacing them as it's usually a destructive removal job. :(

Have a look as this is only a guess. Most of the mods I have done on cars have been on early mitsus and Crowns.

[8>Darren<8]

Thanks Secoh, thats what I was going to do but trying to avoid.

I'll get some spacers turned up for it.

Darren.