drum brake conversion to front only disc brakes & rear drum

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Donald Pirch
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drum brake conversion to front only disc brakes & rear drum

#1 Post by Donald Pirch »

The drum brakes on my 1960 356B just don't get it done in stopping the car in emergency situations - scary as the brakes don't lock up at all. My mechanic Jack Staggs says he has done all he can, but says the material on brake shoes is the real cause as the "good stuff" is no longer available.

Are there good conversion kits out there for my car and who handles them? Is there a better way to make my brakes work better? Help please.

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David Jones
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Re: drum brake conversion to front only disc brakes & rear d

#2 Post by David Jones »

Try this Donald. Just do the front discs, the rears are way too much work mainly because of the handbrake issues.
http://www.airkewld.com/Classic-Porsche ... p/4602.htm
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Pascal Giai
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Re: drum brake conversion to front only disc brakes & rear d

#3 Post by Pascal Giai »

I have a CSP kit on my 59 A Coupe for years and really feel safe while driving fast.
The day I replaced my Normal engine for a SC with big bore kit, the drums were not enough...

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E Rutherford
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Re: drum brake conversion to front only disc brakes & rear d

#4 Post by E Rutherford »

Don,
Jack is very well respected for his skills in the 356 community, so my suggestions aren't second guessing those skills. These suggestions are more for you to evaluate your expectations of the brakes.

It has been my experience that when a customer complains about the drum brake car not stopping, most of the time its because the new brake shoes were not arced to the drums. Pulling the drums, inspecting the shoes almost always reveals less than 50% of the shoe touching the drum during braking. Also, when new shoes are installed they DON"T wear themselves in! Anybody who tells you that, turn around and leave. Arcing shoes to freshly turned drums is critical to a good stopping car. There are still vendors out there that will do this, myself included.

Locking up the brakes in a panic stop - You certainly should be able to lock up the brakes, by accelerating in reverse and slamming on the brakes on dry pavement. Going in a forward motion, not sure I would want to do that on dry pavement. I do a very hard brake test to see if there is any pulling left or right on dry pavement, but never have seen how fast one must go to skid the fronts on dry pavement. I seen a few windshields up close just doing the hard brake test for pulling.

You can still get different brake shoe lining compounds that will stop you on a dime. But for every step forward (quicker stops), there is an equal step backwards (much faster wear on the drum lining).

At the end of the day, you have to feel confident about your car when you get behind the wheel. So if converting to front disc brakes gives you that confidence, go for it.

Hope this was helpful

ed
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Mervyn Hyde
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Re: drum brake conversion to front only disc brakes & rear d

#5 Post by Mervyn Hyde »

David that Willwood kit looks outstanding quality. I see that it does need a master cylinder change, but is a proportioning valve (F/R) needed? BTW I find that since I have re-lined my brake shoes with new, medium-to-hard, kevlar/ceramic based material, I can get straight line lock up on panic braking. With the original Energit linings, they were diamond hard after all these years and I couldn't get decent braking, matter how well adjusted they were and how good the drum lining was. Great improvement in braking now.
Last edited by Mervyn Hyde on Sat Aug 19, 2017 2:17 am, edited 1 time in total.
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David Jones
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Re: drum brake conversion to front only disc brakes & rear d

#6 Post by David Jones »

I hooked up a set of the Willwood disc brakes on a friends outlaw recently. Unfortunately he had bought the VW kit and it is not set up for the rear disc handbrake set up on a 356 so I had to make some mods to make the handbrake work. If you are not equipped to make the changes it would not be a good idea to try and install discs all round. I do not think a proportioning valve is included in the kit and I do not believe one is needed.
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Martin Benade
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Re: drum brake conversion to front only disc brakes & rear d

#7 Post by Martin Benade »

My stock drums work very well going forward but don't seem particularly strong in reverse, when I have 6 trailing shoes and only two leading shoes.
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Graham Kerr
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Re: drum brake conversion to front only disc brakes & rear d

#8 Post by Graham Kerr »

If you want something that is dirt cheap you might want to try fitting 944 front disc brakes. I did some basic measuring and then made a bracket to take the 944 caliper. I put rebuild kits into the calipers and fitted new pads and the car stops really well. I didn't retain the dimensions as it was something of a one off at the time but you can see from the pic the basis of the bracket. Of course this gives you a 5 on 130mm PCD but as my intention for the finished car was to run Fuchs wheels so this was no problem for me.
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