Making the best of stock king pin / swing axle drum brakes

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CaliforniaMilleGhia
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Making the best of stock king pin / swing axle drum brakes

Post by CaliforniaMilleGhia » Fri May 18, 2018 2:50 pm

Hi

if you are using stock drum brakes (class rules) on an early ghia how can you make them the best possible ?

Is there any conversion to use dual front brake cylinders like a bus uses ? Maybe a backing plate from another car like a Volvo or ??????
Is there a little wider brake shoe as the stock ones do not go all the way across to the edge ?

What is the best brake lining to use for street / road use that do not have to be "heated up"
Probably from Porterfield .

Rear Brakes : will a larger rear brake cylinder help anything ?

Wider rear brake shoes if available for stock drums ?

Drums : does drilling "cooling" holes help , or is there any tricks to do with stock cast drums ?

The idea is to have a street car to go for a drive to the store , but also will stop when driven hard up in the Malibu hills when the brakes heat up...

Thanks for your ideas and please tell me if I forgot anything :)

wreck
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Re: Making the best of stock king pin / swing axle drum brakes

Post by wreck » Fri May 18, 2018 4:56 pm

early type 3 rears are larger and are almost a bolt on . you just need to shorten the drum where it slips on to the axle . They make a big difference . you may be able to get the shoes relined with a better material . Also source a 17mm master cylinder .
http://www.shoptalkforums.com/viewtopic.php?t=127619

FJ camper has put up a lot of good info .
No matter where you go , there you are !

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sideshow
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Re: Making the best of stock king pin / swing axle drum brakes

Post by sideshow » Fri May 18, 2018 6:15 pm

356 era brakes are a dual leading shoe stock'ish period correct brake.
Yeah some may call it overkill, but you can't have too much overkill.

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FJCamper
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Re: Making the best of stock king pin / swing axle drum brakes

Post by FJCamper » Sat May 19, 2018 12:46 pm

Better Drum Brakes?

Hi CalifMilleGhia (as in Millemiglia?)

Drilled drums are a really nice improvement. We ran disc front and rear drilled drums on our swing axle Pan American Ghia (3rd in class, 2007) CH Topping in California a drilled our drums for us.

Do I understand you are restricted to stock drums in front by a rule, or by period-correct choice? I've done both myself.

Like Sideshow said, 356 front brakes are a dual leading shoe system, similar to some early VW busses. Not many VW tuners adopted Bus brakes to the Bug because at the time, it was practical and fashionable to just bolt on a 356 drum assembly to a Ghia or Bug. Grafting Bus front brakes to the Bug is a lot of work, involving welding and many axle-related changes.

As for 356 Solex carbs copies for a 36hp VW, a cheaper route is the Kadron (Solex copy) that was derived from the 356 Solexes, but the Kads come with 28mm venturis minimum and a 36hp needs 24 venturis.

FJC

CaliforniaMilleGhia
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Re: Making the best of stock king pin / swing axle drum brakes

Post by CaliforniaMilleGhia » Sat May 19, 2018 7:04 pm

Hi

there is a California Mille like the Italian one so thats what I would like to build to , and period correct drum brakes are needed..... and brake fade is going to be a big problem ,

So no Porsche drums or disc brakes , and when you look at them they need to look stock , along with not much wheel clearance on a Ghia anyway ..... I will ask my buddy what Barndoor front brakes look like , maybe they will give a clue :)

So the best stock drums possible and best brake shoe material , do you have a photo of the pattern that you had drilled ?

I have heard you can do Cryogenic Tempering on drums , any other Voodoo things that I can waste $$$$ on :)

And can you run "modern" brake fluid with old parts ? will the rubber seals survive ? at least the modern stuff does not boil !

As far as the Solex copies , they will look period correct on the early motors , Kadrons will just look wrong ,
I can get "real" early Solexes but the Indian ones are cheap and if an easy tweek to get right can be repeated on other motors ,

Thanks for your advise , you have the hours on the track that most of us will never have

Cheers

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FJCamper
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Re: Making the best of stock king pin / swing axle drum brakes

Post by FJCamper » Sun May 20, 2018 1:20 am

If you can get a decent 32picb copy, I'd go for it. And you'll have the right venturi size.

And yes, Porterfield will reline your VW shoes with better material. We use Porterfield pads in R4 and R4S compounds.

Ventilate the brake backing plates extensively. I don't have the drilling pattern, but C.H. Topping is still in business and they'll know how to do it.

I do recommend a rear camber compensator and if you think running a 19mm front sway bar is too radical, the 1950's tuners would clamp two stock front sway bars together. Remember, the Porsche Speedster got the front sway bar first, then the Ghia, and finally the Bug.

The only really big job is modifying Type 2 front brakes to fit. Run DOT 4 fluid, no synthetics, etc. A trick is to run a larger brake fluid reservoir exposed to cooling air. Everything helps. Back in the bad old days, they tried everything, including heat-sinked brake lines and even water-cooled brake lines. Speaking as one who has cracked a brake bleeder and gotten steam out of it, I know about boiling.

17mm is the stock VW brake master cylinder size for the pre-1966 era. 19mm was for early 911's.

Good luck

FJC

CaliforniaMilleGhia
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Re: Making the best of stock king pin / swing axle drum brakes

Post by CaliforniaMilleGhia » Sun May 20, 2018 10:29 am

is there a way to mount the front sway bar with an adjustable fulcrum point ?
then it could be "adjusted" easily :)

I will look at the bus brakes but may end up using the stock bug ones...

is there any reason to gusset the front trailing arms and spindles ? I know thats what the 356 racers did and the VW off roaders ,

Again thanks for your help ,

CaliforniaMilleGhia
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Re: Making the best of stock king pin / swing axle drum brakes

Post by CaliforniaMilleGhia » Sun May 20, 2018 2:20 pm

I just went out and pulled a stock early bug drum out of the pile ,

the surface is 45-50mm across but the stock shoe is 30mm across.......UMMMMMM

wreck
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Re: Making the best of stock king pin / swing axle drum brakes

Post by wreck » Sun May 20, 2018 4:29 pm

Have a look at early type 3 big 5 stud rear brakes . they just about bolt right on.
No matter where you go , there you are !

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sideshow
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Re: Making the best of stock king pin / swing axle drum brakes

Post by sideshow » Sun May 20, 2018 4:41 pm

I'm not sure better rear brakes would help if anything, it is hard to make them fade with less than hooligan skills.
Since you seem unwilling to change the brakes, the only real alternative is to lighten the vehicle.
Yeah some may call it overkill, but you can't have too much overkill.

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FJCamper
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Re: Making the best of stock king pin / swing axle drum brakes

Post by FJCamper » Sun May 20, 2018 6:45 pm

Image

The wonderful old 32PCIB from my book on Kadron tuning.

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Special Racing Software

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Making it strong -- yes, if the rules allow.

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Not on two wheels. One wheel! Too much front roll stiffness.

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What not to do.

FJC

Steve Arndt
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Re: Making the best of stock king pin / swing axle drum brakes

Post by Steve Arndt » Mon May 21, 2018 10:37 am

"Performance Brakes" in California makes very high quality semi metallic shoes. That will help.

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