> Concerning the Toyota caliper upgrade
> 1. Why is this a good upgrade for my TR3A?
> (which has been sitting for 20 years)
Paul, I'm in the minority here, but IMO it isn't a good upgrade for a TR3A.
It doesn't increase the swept area (which would improve resistance to fade),
so all it does is reduce brake pedal effort. As long as your right foot can
muster enough force to lock the original brakes (which I've never found to
be a problem), then reducing pedal effort isn't going to help.
It's also going to upset the front/rear balance pretty badly, so you're
going to need larger rear wheel cylinders to maintain the balance. Balance
is important because tires stop best while they're still turning. If they
lock completely, they don't brake nearly as well. So, if the front wheels
lock before the rear wheels get to maximum braking, you get less total
FWIW, on my current daily driver, the stock front brakes already lock before
the rear brakes get close. Since I'm already running .70" rear cylinders, I
plan to go to .75" rears. I don't even know if larger ones are available
> 2. Are we talking about the front wheels only or all four?
Front only. I know someone that was working on adapting rear discs to a TR4
last time I saw him, but it's a considerably larger project.
> 3. I am an amatuer mechanic, should I attempt this?
Without meaning to sound insulting, if you have to ask, it would probably be
better if you don't. Especially since these are single-circuit brakes, a
mistake can easily be life-threatening. You (or someone) is going to have
to flare some hard lines, and if one of those flares fails, you'll be
relying on the emergency brake to stop. And they don't stop so good ! (Try
a panic stop with the e-brake sometime when there are no other cars around.
I think you'll be unpleasantly surprised.)