need help pricing drum brakes

I would like to purchase them when you determine a price

Ebay is always an option

[email protected]

 

jlk, what do they include, just the drums, or the entire assembly?

john

 

Is it possible to reline cast aluminum drums?

john

 

John: Yes, new liiners can be installed. We have had Crosthwaite & Gardiner in the UK do them for us.

 

We have had success in the US

 

Were they originally made by casting the drum over a cast iron insert? At the end of the day casting all new drums might be easier than repairing old ones, but it can - without a doubt - be done!

 

Thanks Tom and Dyke, when you get a chance could you send me or post the contact info?

john

 

John: I will let Tom furnish the American contact info first, as they will be easier to work with due to the proximity. If you need the UK info, let me know.

Kare: Ferrari used two methods of alloy drum manufacture:

1. Most drums and all street cars that I know of used an iron (meehanite) liner shrunk into the alloy drum. We have had (on a 250 TR) liners rotate inside this type drum under severe usage. We have "pinned" the liners in place, but with only some success.

2. Some of the race cars ( 410 Sport, 290MM, 290-335 Sport and 412 MI and maybe others) used the English "Alfin" process with the drums made by Wellworthy in England. This uses a iron liner with heavy serations on the outside circumference and the drum is cast around the liner so as to "lock" the liner into the drum. This is the superior method, but is more difficult to produce and more expensive.

3. All the Ferrari drum liners are suceptible to "cracking" under hard usage. I would bet that most drum braked Ferraris today have one or more drums with cracks in the liners.

 

Thanks Dyke. You got my curiosity about the cracks now. I'll look more carefully, though, seems to me you may be referring to the racers and not tourers.

john

 

John: Unfortunately, almost every drum braked street Ferrari I have had apart had at least one drum with some minor cracking (some had more than one drum with cracks). Sometimes the cracks are only surface cracks and sometimes they go almost completely through the liner. To put your mind at ease, in every case with the street cars, the cracks were not going to be a factor in driving safety, so we left the drums alone. What you do have to watch out for is that the cracks will cause a "high" spot in the drum liner and you may need to carefully grind the drum to eliminate this "high" spot.

 

Another issue is corrosion between the liner and drum which can drastically impede heat transfer - this is usually uneven leading to the drums performing well until they get hot when they start snatching as the drum goes out of round. Obviously this is exacerbated under racing conditions.