Rear Z Drums

[Ron Earp]

Z fellows, I don't think my rear drums do much braking and I want to learn how to get them to do some braking.

My wheel cylinders and drums are in good order. I use stock shoes (might bemy problem). When I check my brakes I'm getting plenty of fluid back there and my brake proportioning valve that can restrict rear fluid is fully open. When I go to service my brakes I do have some shoe wear, but not much. Sure, there is dust back there, but my drums are blue and cracking to pieces, far from it. I've been running the same set of shoes for like a year.

Do I need to use Carbotech shoes? I'm adjusting my brakes out as far as possible either manually when I service my rears, or by using the parking brake. I can tell slight differences when I get them adjusted out, but I still don't feel like I'm getting a lot of braking back there. Definitely can't lock them up, or at least, the fronts are far and away locked up long before the backs think about it.

Any pointers?

[Parrish57]

I tried for a long time to use Pep Boys shoes but they were always either ineffective, glazed over, or crumbled under pressure. I went to the Carbotech rears and stepped up my brake program a TON. They don't last very long but that's racin' life. If you want to play, you got to pay.....

[jrvisual]

I am the Regional distributor for Airotech brakes. They are nearly as effective as improperly adjusted stock shoes and offer 100% weight savings over Carbotechs or any other shoes. Reduce that all important unsprung weight.

One change in driving technique is required for use. To apply the Airotech brakes one must release the clutch and let the engine engage on each downshift.

Airotechs are only $300 a set and come with a lifetime warranty. They are guaranteed to never wear and will also extend the life of your drums.

[spawpoet]

Steve, How long do the carbotechs last if your using you rear brakes enough? We've had better results in auto-x with the carbotech shoes as well. Also what do they run new? I got mine from somebody who just wanted to get rid of a couple of sets.

chris

[spawpoet]

Jeff that had me rolling on the floor, but now has me asking how tight is too tight on the adjustment? Just figured out Sat. that I've been using Airotech shoes on my right side the last two events. I thought if anything I had been a little tight on my last adjustment, but I was a good bit loose on the right and them drum came right off. Left side seemed fine, and the drum took a little finagling to get off like i thought they should.

chris

[Parrish57]

I am the Regional distributor for Airotech brakes. They are nearly as effective as improperly adjusted stock shoes and offer 100% weight savings over Carbotechs or any other shoes. Reduce that all important unsprung weight.

One change in driving technique is required for use. To apply the Airotech brakes one must release the clutch and let the engine engage on each downshift.

Airotechs are only $300 a set and come with a lifetime warranty. They are guaranteed to never wear and will also extend the life of your drums.

Sign me up!! 100% weight savings! I'll buy 3 sets....

[Parrish57]

Steve, How long do the carbotechs last if your using you rear brakes enough? We've had better results in auto-x with the carbotech shoes as well. Also what do they run new? I got mine from somebody who just wanted to get rid of a couple of sets.

chris

I'm told that I probably adjust them too tight but I prefer being able to stop. Mine last about 3 races (depending on the length of course) and they are about $125 per set. I've said this a few times today but here goes: If you want to play you've got to pay!

[jrvisual]

Steve,

I don't want to rip you off. Unless you have 3 cars, I won't sell you three sets. They are guarantee to never wear out.

Just sent the $300 to my paypal account and remove your old shoes and you will be good to go.

[jrvisual]

http://www.ctbrakes.com/pads/nissan.html

I don't see the rear shoes on the carbotech site. Where do you get them?

[Parrish57]

Just call them on the 800 number.... They'll fix your wagon!

[jrvisual]

"Carbotech™ 912 Kelated Metallic™: An advance organic-metallic compound specially formulated for drum shoe applications in lighter weight race cars and/or high performance street vehicles. High friction coefficient of 0.46 to 0.48, providing excellent braking without any risk of lock-up. Very good brake modulation throughout the entire brake pedal travel range, with excellent wear characteristics, providing an outstanding value. With a price-point significantly below other compounds offering similar performance, 912 ™ is an excellent choice for the budget-minded racer or high-performance driver. Optimal recommended operating temperature range is from ambient to 650°F."

Are you using this drum specific compound?

[JeffYoung]

Porterfield has an off the shelf race compound as well, R4, that you can order on line for the same ($129) price.

[jrvisual]

I may have some new Porterfield shoes in the boxes of brake parts that I bought from the guy in VA. I'll look next weekend when I am home. I know I have new front pads, not sure about the shoes. You are welcome to try them if I have them. The more experimenting you do the less I have to do.

[JeffYoung]

Check the compound type. Apparently R4 is good, R4-S is not.

[irondragon]

Ron:
You have joined the Club!!
Now you know - Datsun Z-cars, at least the 240-280 series, don't have any rear brakes.
This explains why we are on the brake at the 300 marker and get passed by all the cars that don't show any lights until the 100.
Ah, but after we get out of the turn we have buckets of acceleration to pass the little pissants.
What to do about this?? Not much
Rear shoes from Carbotech, or Nismo Greenstuff if you can still get it, will help.
Diligent attention to rear brake adjustment will aslo help, a little.
If your car has a working hand brake you can use it to tighten up the rear brakes by pulling up on it a bit during the race.
But your best solution to this is to make sure your motor pulls like a steam locomotive, which it certainly can.
Best Regards Bill Miskoe Iron Dragon Racing

[JeffYoung]

After 5 laps, my car has no FRONT brakes either. No wait, we've mostly licked that one.

I am a long lost cousin of the Z, in the sense that I too am shackled with the front discs/rear drums albatross around my brake pedal. Ron and I work on each others cars, and we have both noticed the same thing. With stock compound, you can put the bias adjuster all the way back and not get much rear action (much less any lock up), stock shoes seem to last forever, and there just at much brake dirt back there.

I'm making the switch to Carbotechs or P-fields since I have to step up my program to compete with Steve's NASA fuel powered Z. Here was a suggestion I heard that seemed to me to be a BAD idea.

Put a proportioning valve in the front circuit in order to crank DOWN the front brake pressure. Hence, giving LESS front brake (bad in my view) but more rear bias (the intended result).

I say no no no no but interested in the collective wisdom of the Cult of Zness.

[Ron Earp]

. Here was a suggestion I heard that seemed to me to be a BAD idea.

Put a proportioning valve in the front circuit in order to crank DOWN the front brake pressure. Hence, giving LESS front brake (bad in my view) but more rear bias (the intended result).

I think that is a Super Bad Idea.

The result is that you've not actually increased the absolute rear brake effectiveness at all. It remains the same. What you've done is increased the relative rear brake effectiveness in relation to the front by reducing the front effectiveness. Since the fronts are doing most of the work, your stopping distances are going to increase.

I'll not be party to rigging that one up for you, but if you do it I'll video you from BEHIND going into turn 1!

Steve or anyone else, what do Carbotechs look like? Any distinguishing marks? I've got lots of shoes with the Z spares kit, I just don't know what any of them are. And, since the ones on the car seem to be made from Everlast I've not really looked at the spare shoes in any detail.

[JeffYoung]

They are a whiter/lighter material. Remember also that they expand making it a beeyotch to get the drums off.

Agree with you on the prop valve in the front line. Reducing the brakes that actually work ain't making no sense to this flyboy.

[Ron Earp]

They are a whiter/lighter material. Remember also that they expand making it a beeyotch to get the drums off.

How could it be harder? The last time you and Jeffrey had to cut the drums into tiny little pieces.

[JeffYoung]

Those were Carbotechs I think. Steve P. will post here. He's the one, and Rex I think, that told us about it. They swell on first use.