Alternate 240Z rear brakes...?

[GKR_17]

I suspect the drums are cast iron, not steel. Using iron instead of aluminum is not a safety issue. Sure it will run hotter, but iron will take it where aluminum will not. Aluminum is very rarely used in brakes, and for good reason.

If you really want to talk safety I move we ban the stock drums.

[Ron Earp]

I suspect the drums are cast iron, not steel. Using iron instead of aluminum is not a safety issue. Sure it will run hotter, but iron will take it where aluminum will not. Aluminum is very rarely used in brakes, and for good reason.

If you really want to talk safety I move we ban the stock drums.

Yep, I think you're right on the cast iron. Been awhile since I looked though.

Now on the "ally drums" I'm pretty sure that is an ally drum, with fins cast in it, with a steel insert. Carbotechs can handle the heat and I was just talking with those guys a few weeks ago and they have a compound for shoes that can handle even more heat than the previous versions.

I'm not a Z historian but are these ally legal in the first place??? My 260Z shop manual doesn't show drawings of finned drums, but of round drums with no fins. Were the fins added by NIMSO for performance reasons and were they listed as an alternative part number by Datsun/Nissan?

I'm with you though. I'd like to ban the blasted things for selfish "don't want to ever work on a drum brake again" reasons, but I am logical enough to know that isn't something to pursue. Funny how one of my prime motivators for getting a new IT car is to get something that doesn't have drum brakes and carbs.

[dspillrat]

Every 240 I've ever pulled apart, had fins.......

Now I have seen 3 vented rotors as well....vented rotor caps that is.....

Didn't realize the olds came with drums.... I Need a letter penned Jeff...

David

[GKR_17]

I'm with you though. I'd like to ban the blasted things for selfish "don't want to ever work on a drum brake again" reasons, but I am logical enough to know that isn't something to pursue.

I was really kidding, but was trying to say that if safety is the arguement then make them run the iron drums. I vote a big no to the disc swap. Not sure how to handle the Olds, I'd rather it get pulled than be a precident further creep.

[JeffYoung]

Somebody send a letter in....we need to get that Olds exception deleted.

[pballance]

Yep, I think you're right on the cast iron. Been awhile since I looked though.

Now on the "ally drums" I'm pretty sure that is an ally drum, with fins cast in it, with a steel insert. ................

I'm not a Z historian but are these ally legal in the first place??? My 260Z shop manual doesn't show drawings of finned drums, but of round drums with no fins. Were the fins added by NIMSO for performance reasons and were they listed as an alternative part number by Datsun/Nissan?

...............

They were all finned Ron. Aluminum drum with steel insert. They can be re-sleeved if you will. Not cheap but it can be done. I think JohnC at Betamotorsports was looking into that for one of his customers. Also, the new aftermarket's are cast and are without fins.

My drum backing plates are vented and there was evidence of a rear ducting system being attached to the rear control arms at one time. One of the previous owners of my car ran it in enduros on the west coast.

While I agree it would be nice to do away with the drums, as a Z racer I wll argue that it is against the class philosophy and an allowance should not be made. Like Jeff, I have another Z waiting in the wings that actually has discs all the way around

BTW, I will try to get a picture or two up for the Nissan fans. I have a buddy that has a Nissan IMSA GTP in his shop. Pretty neat car.....

[spawpoet]

"My drum backing plates are vented and there was evidence of a rear ducting system being attached to the rear control arms at one time. One of the previous owners of my car ran it in enduros on the west coast."



It was always my understanding that the cast drums were preferred on z's for enduros anyways. I don't know from personal experience, and have no idea if it's true, but the internet lore was always use the alloy drums for auto-x and sprint races, and the cast for the long races because they dealt with extended periods at high temp better.

[Eagle7]

They were all finned Ron. Aluminum drum with steel insert.

If that's the case, then how can a steel aftermarket drum be considered a legal equivalent?

[JeffYoung]

It's unclear if the cars ever came with steel drums. If not, I agree, it's technically illegal.

But, I sure wouldn't want to be the guy who protested that.....

If that's the case, then how can a steel aftermarket drum be considered a legal equivalent?

[Ron Earp]

If that's the case, then how can a steel aftermarket drum be considered a legal equivalent?

It wouldn't be.

I just spoke with Riley at Lynchburg Nissan, probably the best Z parts man in the country. He says that Z cars came ONLY with finned aluminum drums. The 510s used steel drums, and of course those guys switched to Z drums for the competition setup.

So, steel aftermarket drums are technically illegal as no Z car was ever equipped with them. Since the aluminum drums are NLA (even Ebay only pulls up one drum right now) we are in sort of a pickle.

Riley also passed on other information about the drums. They were produced for Brembo/Nissan from a company in Italy. Brembo owns molds, but the other company does the production and they pulled the plug on production with only a few 100 orders for year. The molds are tied up at the company and it'll take a 1000+ unit order for them to do another run of them, which isn't going to happen.

Now, switching a 240/260/280 to disc rears isn't as easy at it sounds. According to Riley the 280ZX stuff does not bolt up, but, other OEM parts do. One is supposed to use a Maxima caliper bracket from 83/84 and 200sx calipers/rotors, from 82/83, mounted upside down to pull it off.

So, 240/260/280 drum brake racers might need to consider lobbying for some sort of rule change because racing with steel drums is technically illegal.

[lateapex911]

Regarding the GM issue, if the ITAC were to get a letter asking for the removal of the exception, I think it would be seen as a reasonable request, and we'd discuss the merits. IF we supported the removal, we'd add a "sunset clause" of a year or two for the Calais nation to source the parts.

FWIW, 1st gen RX-7s face a similar issue. Engine parts are NLA. There is a plating system available aftermarket, but the finished plating differs from stock in material, but not performance, and is therefor illegal.

[Greg Amy]

So, 240/260/280 drum brake racers might need to consider lobbying for some sort of rule change because racing with steel drums is technically illegal.

GCR/ITCS 9.1.3.C says, in part:

"Documentation of the superseding parts or assemblies must be supplied to the Club Racing Department and the appropriate part numbers listed on that particular model’s specification line."

If you saunter down to your local Nissan dealership and order a pair of rear drums for a Z-car, what will you get? I'll wager a dollar you'll get a pair of steel drums. As such, the steel ones are not only legal, they're the only legal new part for the car. So, no lobbying needed, all one needs to do is provide the Club Racing Department with valid documentation that the aluminum parts are no longer available, and ask them to spec on the line that steel equivalents are expressly legal (although I can't imagine anyone dropping the money and effort to protest you for that). Contact Paul St. Clair at NisMo; I bet he can provide that to you same-day via FAX or email.

On the other hand, if you guys really think you'll get rear discs approved for the car simply because the aluminum drums are no longer available, well you're smokin' the funny stuff -- and this month's Fastrack should have put that idea to bed pretty quickly... - GA

[spawpoet]

Anyone have a clue how much it would cost to have warn out drums re-lined?

[Ron Earp]

On the other hand, if you guys really think you'll get rear discs approved for the car simply because the aluminum drums are no longer available, well you're smokin' the funny stuff -- and this month's Fastrack should have put that idea to bed pretty quickly... - GA

No Greg, I think if you read what I and others have written nobody here (except for the thread starter) is going to ask for disc rear allowance. I simply wrote what Riley passed on to me so that folks could see what was involved with putting drums on the rear of a Z car. It isn't a simple swap over from a 280zx.

My mistake in my post was writing "lobbying for a rule change" when I meant lobbying to have steel drums approved. I had forgotten about the part supercede pathway and I'm sure that Lynchburg Nissan/Riley will provide this documentation.