The Cal-look Lounge

Hi guys

I am renewing the 5 stud rear brakes on my bug and was wondering if there are any simple upgrades that I can make while I'm at it

I think I remember reading that you can use 1303 drum front cylinders as an upgrade ,as they are slightly larger ??

don't have the money for type 3 or 356 drums but any tips welcome

Regards Ron

Ron, do you have front discs? If so, you can use front wheel cylinders in the rear drums to get the balance back a little, especially as the front tyres will probably be quite skinny. Go for the latest parts that will fit, so '66 drums and internals (I'm guessing you're putting them on the '59), and you may even be able to space the drums out a little to fit later (wider) shoes.

Hi Neil

yes they are for the '59 . I've front drums at the minute but will change to discs when funds allow

I am collecting late 60's 5 stud drums and backing plates this weekend as the 59 ones were really small  and used the early two bolt cylinders.   

Would you not use larger cylinders when you have drums up front  ??

that would disturb the brake balance ron.
front discs are stronger so then you can upgrade the rear brakes, too, to regain a good proportion.

maybe I'll go for standard cylinders for now then

Try to find someone to arc the shoes to the drum...

What tyres are you using front and rear?

Bruce

155 up front and 205 70 15 rear

Jim

could you explain "arc the shoes ""

Thanks Ron

Arcing the shoes is rarely done today, but it is one of the best ways to improve stock drum brakes.  First the drum is turned then the shoe is ground to ensure that the shoe is the the same shape as the drum and makes contact over it's entire surface.  The brakes last longer when this is done and they work better.  I had a pair of front brake shoes last over 100k miles and they had worn evenly and not down to the metal.  You will probably need to find an old garage to do it.  In the U.S. the EPA has pretty much stepped in and stopped it because the dust from the process is unhealthy.

When your car was designed, it was intended to have the rear tyres the same as your fronts.  You have done two things that have reduced your car's braking ability. 

First, you have replaced the light 155 tyres with heavy flywheel tyres.  For that, you need more rear braking capacity.  The second thing you've done is increased the diameter of the rear tyres, giving the existing brakes less leverage.

The low cost cure is to increase your rear brakes as much as you can.  That means to go all the way up to a 1302/1303 front wheel cylinder, installed in the rear.

thanks for you help guys, looks like I've some work to do  ;D

Regards Ron

Big motor's = bigger stopping power , tread carfully  :)

Ron it only as fast as your right foot wants it to be. ;D

Arcing the shoes will not "improve" your drum brakes, but it is intended to make them work as best as possible when new shoes are installed.
Beetle drums are 9 inches in diameter new, their wear limit is 9.065". Drums are "turned" to remove grooves, ridges and general defects. If they are within wear limits, then they are fit for service.
New shoes are made by laminating or riveting the lining to the shoe. They are made with a lining material that is one consistent thickness. This can make the new shoe's radius over 9". To make the lining contact the drum properly, the shoes can be "arced" to the diameter of the individual drum. A shoe arcing machine is a sander with a jig that holds the shoe firmly in place. You set the machine to radius the shoes to almost match the diameter of the drums. I say almost because actually you want the new shoes to be radiused to a slightly smaller diameter than the drums. You want the shoes to contact in the center before the ends contact. A new shoe that is properly radiused and arced to the drum will "rock" when it is placed in the drum by hand. You want the center of the shoe to contact first. The difference is very slight, only .030" or so. The mechanical force of the brakes being applied will force the shoes into the actual diameter of the drum.  This was done to ensure that you will have 100% performance from the new shoes right from the start. If not done, the ends of the shoes can contact the drum first, you will have less mechanical advantage, and  they may chatter, resonate or make noise on application. And, arcing the shoes is removing some of the lining material, so in theory, it should not increase the life of the linings .
When OSHA (Occupational Health and Safety Administration) stepped in and said Asbestoes dust was unhealthful to breath, that eliminated the arcing of shoes to drums. When you install new shoes nowadays, you can only hope that the radius of  the new shoes will be slightly smaller than your drums. If not, they will just have to wear in. You may not have 100% effectiveness right from the start, but they will eventually conform to the diameter of the drum just by wear.
So, at the end of the day you still have 9" brakes on the back of a stock Beetle.
Type III rear drum brakes or rear discs are the way to better brake overall performance IMHO.

Thanks for your reply , very informative

Regards Ron