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Hello,
My brake drums are pretty shot on my 73 Z and I was wondering how big of ajob is it to replace the drums and shoes and is it worth it or should I replace my front calipers with the 4 barrel upgrade?
What gives me more stoping power my drums or the disk?
Which is cheaper?
Anything special I need to know about these drum to work on them??

Dustin Morris
 

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I replaced my rear drums with new aluminum drums from NAPA (Made in Italy). Watch out --- a ridge in the outer groove that fits over the backplate needed to be ground down to mate properly.
I'm in the process of upgrading to the Toyota 4 piston caliper in front. This should be fine for daily bonzaii runs, but for autocross or more, you will likely want disk in back. I'm not an expert though.

> Hello,
> My brake drums are pretty shot on my 73 Z
> and I was wondering how big of ajob is it to
> replace the drums and shoes and is it worth
> it or should I replace my front calipers
> with the 4 barrel upgrade?
> What gives me more stoping power my drums or
> the disk?
> Which is cheaper?
> Anything special I need to know about these
> drum to work on them??

> Dustin Morris
 

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482 Posts
Brake info

> Hello,
> My brake drums are pretty shot on my 73 Z
> and I was wondering how big of ajob is it to
> replace the drums and shoes and is it worth
> it or should I replace my front calipers
> with the 4 barrel upgrade?

You're asking two different questions here. First, if you're stock rear drums are worn, then most likely you would need to replace them or have them turned. It is not a big deal to remove it, unless the drum is stuck to the hub. It is removed by just banging it gently from the back until it pops off the hub. No screws or anything, it relies on the wheel and lug nuts to keep it in place as well as a light press fit. If it is stuck, you can apply some gentle heat with a torch to loosen the fit, then try tapping it off. A little cussing helps.

Second, about the Toyota 4 pistons. The 4 pistons offer a larger pad and more brake pressure. You should install the Master cylinder from a 280ZX. It's bore is 15/16 compared to 7/8 for a 240Z. Braking will be significantly improved. I would recommend it. They bolt right on, no modification necessary except minor tubing bending and removal of the dust shield. Maybe add some stainless braided lines while you're at it. A better pedal feel, and most likely your originals are worn anyway.

> What gives me more stoping power my drums or
> the disk?
The ability of a braking system to stop a car or anything else is dependent upon several factors. One is the coefficient of friction, or the amount of force required to make the material start to slip. The higher the coefficient, the harder it will be to move. Second, is brake torque. Think of this as a lever. For instance, you use a 'cheater' bar to get highly torqued nuts off right? The reason this works so well, even though you can't lift more weight, is that it uses the mechanical advantage of the bar length to multiply your force, enabling you to turn the nut. The same idea is used with brakes. The farther away the caliper is from the center of the hub, the more pressure it can apply over a greater area, thus better braking. This is why 11 discs are better than 10. Think of a spinning wheel. The center may move at 50rpm, and the further you get from center, the less rpm the wheel moves. This means less work will be involved in stopping the wheel the further away from the wheel you get. Lastly, heat must be considered. This is the downfall of drums, since they cannot dissipate heat as fast as they generate it. Discs, however, have a large surface area that is directly exposed to air, enabling them to radiate heat rather easily and quickly.

> Which is cheaper?
I prefer discs, due to the ease of changing pads, and rotor inspection as well as better stopping ability. But, there are plenty of drums in junkyards in good condition, and as long as they are plentiful, they will be cheap.

> Anything special I need to know about these
> drum to work on them??
They can be a b**ch to get off at first.
 
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