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Volkswagen Brakes
The stock front and rear drums provide sufficient braking for a stock weight air cooled VW. The only problem with the stock setup is that it does require frequent adjustments and braking fades if the driver is braking aggressively. The stock braking setup is also made for street use, which is configured differently than what you might want to run on an offroad vehicle.
Like most passenger cars, 75-80% of a stock VW Beetle's braking power occurs at the front tires when on paved roads. This mismatch of front and rear braking occurs as weight/traction is transferred to the front of the vehicle under hard braking. But for offroad braking over loose terrain, stock proportioning that allows the front brakes to brake harder than the rears will cause the front end to lockup and slide, which results in a loss of steering ability. And since stock VWs are light in the front, this phenomenon is intensified. Offroad modifications such as moving the fuel tank to the rear of the vehicle and adding larger tires in the rear further magnifies this problem.
So for street use, the best thing you can do for braking, other than learning advanced driving skills, is to replace the stock front VW brakes with disc brakes. And the best thing for a VW used strictly for offroad use, is to increase the braking ability of the rear brakes.
Front Discs
For street autos, replacing front drum brakes with disc brakes will make a noticeable improvement on braking, especially if you are braking enough to notice fading.
A great "stock" VW conversion for Type 1 Bug with a balljoint front end (4 lug) is to use parts for/from a VW Karmann Ghia with a ball joint frontend. You will need to remove the stock spindles on the Type 1 you are converting and install the disc brake spindles, calipers, rotors and brake pads for a Karmann Ghia. A simple alignment adjustment and break bleed is the only thing else that is needed.
There are many after market disc brake conversions for VW. Some are race quality while others have questionable quality.
Rear Discs
This is generally overkill for most street autos, but when combined with front discs allows for you to go without brake adjustments and make pad changes much easier. For offroad only vehicles, these help you lock up your rears for quick turns without the fade from the stock rear drums.
Other Brake Upgrades
There are other ways to upgrade your brakes without going to heavier and more expensive disc brakes.
http://www.1800vw.bizhosting.com/brakehowto.htm
http://www.1800vw.bizhosting.com/brakedrums.htm - Drum sizes
Drum Wheel Cylinders
The larger your wheel cylinders, the greater the braking potential (assuming your master cylinder and tire traction is up to the challenge). A stock VW Beetle comes with about a 22mm wheel cylinder in the front and a 17mm one in the rear. This is sufficient for most "normal" street use. For offroad use, you may want to decrease the braking power of the front by installing a proportioning valve in the front to decrease brake pressure their, or by altering your brake hardware configuration.
A 68 or later rear 17mm wheel cylinders (11 361 1053B) can be installed in the a Type 1 Beetle kingpin or ball joint front end to decrease the front braking potential.
A stock 71-on Beetle and need a little less braking up front you can use the
The rear T3 - 65-73 22mm wheel cylinders (311 611 067C) can be used in lieu of the standard 23.8mm cylinder (361 611 067A) normally used on the front of 1971-79 Super Beetles to decrease front braking
Other wheel cylinders can be switched around to the front, but you will need to check the distance from the backing plate to the center of the shoe first.
The rear brakes require more than just installing a new wheel cylinder if you are using a swing Axle trans. (up to 67). First you must replace the swing axle backing plates with 68 or later IRS ones. The IRS backing plates allow you to install 57-on ( 131 611 057 ) 22mm wheel cylinders. (Note: You can NOT use the wider 1 5/8" 68-on brake shoes with the stock 5-lug brake drums).
On the rear of 68-on IRS Beetles, you can install the larger 22mm wheel wheel cylinder (131 611 057) or switch to a rear T3 Brakes setup. The 68-on IRS rear brakes also have a wider ~1 5/8" brake shoe than the 1 3/16" wide swing axle shoes.
The Type-3 rear brake (65 & earlier for 5-lug drums) linings are wider ( 1-3/4") than those on Type-1s, the drum diameter is larger and they already have 22mm wheel cylinders. You can also upgrade the wheel cylinders to use the 23.8mm (361 611 067A) front SB wheel cylinders with the T3 rear brakes. If you get the complete setup with backing plate; drums and all it's an easy bolt on installation. 5-lug axle splines are 1 7/8" & 4-lug axel splines are 2 1/2" long. You will have to remove about .550" off the outside snout of the drum to use these with a short swing axle transmission.
There are other set ups that can be made to work, to include
some type-2 and "Thing" brake upgrades. These other options often
require hard to find parts and the cost of these modifications may be
higher than just converting your brake system to discs.
Residual Pressure Valves
Some recommend installing 2-psi residual pressure valve when upgrading to disc brakes to allow for better pedal feel. This should be installed as close to the master cylinder as possible if it does not screw directly into the master cylinder. And if your master cylinder is lower than your brake calipers, a residual pressure valve is required.
The 10 psi residual pressure valve is only used with Drum Brakes.
Master Cylinder
As the Master cylinder diameter gets smaller less pedal pressure is required for the same amount of braking. The larger the master cylinder bore, the more pedal pressure is required for the same braking.
The most common master cylinder used on buggies is the early type-2 (211
611 011J) 22mm which can be used with rear disc and 17mm front cylinders.
If everything is set up correctly, there is sufficient amount of available
hydraulic fluid for braking. But if the rotors are not true or the front
brakes are out of adjustment, this may push you past the limits of a what
a 22mm bore master cylinder is capable of.
Neal and other brake builders offer several different MC bore diameters, 5/8" to 1".
Brake Pads
Never allow oil on your brake linings. Some also advise against
"brake clean" as this dissolves oil and allows it travel deeper into the
lining. Some race mechanics won't let you touch the lining as even the oil
off your hands is not wanted. Other mechanics won't let you touch
anything.
Brake Fluid
Use Dot-3 fluid (never Silicon brake fluid) and flush your brake lines every two years.
The hot & cold, sun and shade experience by many Bajas and buggies with exposed brake lines has the tendency of increasing the amount of moisture in the brake lines compared to the lines under a stock car.
You can flush the brake lines with brake fluid, dry air or alcohol. Note that a single drop of oil in the fluid will contaminate it.
Brake Hoses
The stock hoses swell when pressure is applied to the brake lines. So some of the forces applied to the brake system are lost through the hoses. These hoses also can fail.
Steel braided brake hoses will help transmit more the the brake line pressures to the calipers. This increases foot pedal firmness and increases braking efficiency.
Brake Lines
The stock ones will eventually rust one from the inside out and leak. The fittings can also "suck air" into the lines, even without noticeable leaks. The rear line runs inside the passenger compartment out the back and between the body frame to the left brake. There is a potential that the brake line going to the left side can get pinched when the body and frame come in contact and if you band the transmission against the exposed line over the front of where the transmission nose should go
Steering/Cutting Brakes
The Steering brake or Cutting brake can be very useful when you have a very light front end. It allows you to shorten your turn radius and make quick maneuvers offroad.
Some prefer the Dual Handle brakes when drag racing or running in the dunes, as you can apply both rear brakes at the same time. For offroading, many prefer the Single Handle, as when you grab it, it is always the correct handle. Why? In a panic situation, it is beset that you not pull the wrong handle. And in rough terrain, your body can move around quite a lot and you may not have luxury of looking look down to see which handle you have grabbed.
After a short time pulling or pushing will become automatic just like pushing the clutch or brake.
Steering brakes are often blamed when other brake problems occur. To check if the steering brake is working properly, just apply a slight amount of brake with the foot pedal and then work the steering brake. If it's tight and the handle doesn't keep moving then the problem is else where. The turning brake also do not move a lot of fluid, so you will need to keep the brakes properly adjusted.
The stock emergency brake cable system may not reliable offroad, as your cables may catch on something and jerk the cables off.
The Park-Lock can be installed in the brake line and seems to work great.
Brake Adjustments
The stock drum brakes need frequent adjustment for proper brake function. They must be adjusted a little different then most cars. Tighten/adjust them until you have a slight drag and then hit the brake pedal hard to center the shoes and adjust again. Proper setup means that after you have 4 or 5 times and jack up your auto, the car still has a very slight drag when the wheel is turned.
To check if the front/rear brake bias is correct, have a friend stand off to one side and then as you pass him apply the brakes gradually until you lock up all four wheels. If your friend thinks that the front end locked up just before the rear wheels locked up, you are set up just right. This should be done on both dirt and gravel if you are doing a lot of offroading.
Conversion Bearings
Allows you to install ball joint rotors onto king pin spindles.
http://www.appletreeauto.com/k-p-conv-bearing-innerea-c-124-p-1-pr-5491.html Part number 17-2795-0
http://www.appletreeauto.com/k-p-conv-bearing-outer-ea-c-124-p-1-pr-5495.html Part number 17-2796-0
1.57 x .787
1.980 x .985
Brake Part Numbers
Wheel Cylinders
T-1 Wheel Cylinders
Rear 57-7/64 113 611 055C Rear 64-7/67 131 611 055 fit `58 through `64 Rear 67-on 113 611 053B used on the front of Buggies, will not fit some 1957s Rear T-3 65-73 311 611 067C 22mm (7/8") 361 611 067A 23.8mm (15/16") used on early Squarebacks and also on SuperBeetle fronts; not interchangeable except in pairs Front 52-58 113 611 055 Front 57-7/64 113 611 057B Front 7/64- on except SB 131 611 057 used on Buggy Rear with IRS Backing Plates for better brakes, 113 611 055 and 131 611 057 can be interchanged if needed (only difference is the width of the slot)
T-2 Wheel Cylinders
Rear 56-7/71 211 611 047C Rear 72-on 211 611 047D Front 55-7/63Ft/Left 211 611 069 Front 55-7/63 Ft/Right 211 611 070 Front 63-7/70 Ft/Left 211 611 069C Front 63-7/70 Ft/Right 211 611 070C
Brake Shoes & Pads
T-1 Brake Shoes
Front 10/57-7/64 113 609 237D similar to 131 609 237C, the only difference being that the latter have angled ends at the adjuster. If you use the 1965+ adjuster, 131 609 237C fit `58-`64 as well. Front 8/64-on 131 609 237C Front 8/70-on 113 609 237H Super Beetle only Rear 10/57-7/64 113 609 537B similar to 131 609 537C, the only difference being that the latter have angled ends at the adjuster; linings wear less unevenly with the angled adjuster/shoe arrangement. Rear 8/64-7/67 131 609 537C Rear 8/67-79 113 609 537C
It's common these days to find new shoes made on frames which allow them to be used on either the front or rear (they have both the slot the e-brake bar and both return spring hole arrangements). You've always been able to use a "rear" shoe on the (same-width) front by simply drilling one return spring hole in it.
brake industry standard P/N for `68+ rear shoes 10153 `65+ front 10142 `65-`67 rear 10143 `58-`64 front 10078 `58-`64 rear 10079 Super front 10199 Type III rear 10140 `55-`63 Bus rear 10077 `64-`70 Bus front 10114 `72 Bus (rear) 10215 `73↑ Bus (rear) 10231
T-2 Brake Shoes
Ft. 3/55-7/63 211 609 237B Ft. 8/63-7/70 211 609 237D Rear 3/55-7/63 211 609 537B Rear 8/63-7/70 211 609 537E Rear 8/70-7/72 211 609 537J Rear 8/72-73 211 609 533B Rear 8/72-79 211 609 537N
T-3 Rear Brake Shoe
Rear 8/63-74 311 609 537D
Disc Brake Pads & Buggy Rear
Buggy rear Disc 311 698 151 fits Varga calipers 311 615 107/8; 2 3/16" x 2 1/16" T-1 & Ghia up-72 111 698 151A SB & Ghia 8/72-79 111 698 151B T-2 8/70-7/72 211 698 151D T-2 8/72-7/79 211 698 151C T-3 8/65-7/71 311 698 151 T-3&4 8/71-73 311 698 151C
Emergency Brake Cables & Spring Kits
T-1 . E-Brake Cables
8/57-12/64 1742mm/68.6" 113 609 721F 1/65-7/67 1779mm/70" 113 609 721L AT 8/68-7/72 1810mm/71" 113 609 721J MT 8/67-7/72 1773mm/69.8" 113 609 721M 8/72-8/79 1749mm/68.8" 133 609 721
T-2 . E-Brake Cables
wo/servo Cable 3/68-8/71 3435mm/135.2" 211 609 721L w/servo Cable 8/69-7/71 3435mm/135.4" 211 609 721P Brake Cable 8/71-7/79 2960mm/116.5" 211 609 721T
Brake Shoe Retaining KitConsists of 2 springs, 2 pins, 2 retainers (requires 2-kits per wheel)
311 698 071 Front - std 65-78 & Rear 68-79; Ghia Rear, 68-74; Thing F/R 73-74
211 698 072 T-2 Brake Shoe retainers 64-on 1 5/8" long Pin
Drum Brake Hardware Kits
2 Wheels Front 58-64 113 698 301 2 Wheels Front 65-79 113 698 162 2 Wheels Rear 58-79 113 698 003
Rear Brake Drums
Rear 4-Lug Brake Drum
4-Lug Brake Drums are about 9 1/8" I.D. with 2.5" spine length and use the 1 3/32" wide brake shoes.
# 113 501 615J
5-Lug Brake Drums
Used up to 1968. Drum I.D.=9 1/8" with axle spline length of 1 7/8", Brake shoe used is 1 3/32" wide. The 5-Lug Bolt Pattern is 205mm. # 113 501 615D
5-Lug "VW Thing" Rear Drum
Easy way to use 5-lug wheels instead of the stock 4-lug as used on 68 and later T-1
The VW Thing uses same Backing Plates & Brk Shoes as 68-on T-1. Plus increase tread width approximately 1 1/8".
Drum I.D.= 9 1/8" dia. and uses the 1 3/32" wide brake Shoe. The axle spline length is 2.5" long.# 181 501 615A
T-3 Rear Brake Drum
It is Larger in Diameter and uses Wider brake Shoes then the T-1 or Thing. It also uses larger wheel cylinder then the T-1. Often used to upgrade the rear drum brakes. Brake Drum is 9 13/16" dia. & uses the 1 3/4" wide Shoe. Axle spline length is 2.5" long.# 311 501 615E
Other
Brake Pedal Return Spring 131 721 163 Backing Plate Plugs 113 609 163A Brake Adjusting Stars 113 609 205A Brake Adjusting Screws 113 609 209 Brake Bleeder Screw Valves 211 611 477A Brake Bleeder Screw Dirt Caps 211 611 483 Brake & Clutch Pedal Rubber Pedal Pads 311 721 173
Brake Hoses
9.25" . Rear 68-on IRS 113 611 775E 10.8" . Rear (FF) Rear IRS 211 611 775B 12.75" . Front SB (FF) 74-79 113 611 701E 13.5" . Front 67-78 w/disk Brk. & T3 67-73 311 611 701B 14.5" . Front 8/66-78 (not SB) 113 611 701D 17" . Front 56-66 211 611 701 18.5" . Front 60-64 113 611 701
Metal Brake Lines "Metric"
6.5" 165mm 113611735F 7.375" L/Front >-7/66 113611723A 7.5" L/Rear T to Hose SA 113611763A 10.25" 260mm 113611736D 12" "T" to Hose 71-79 SB 113611723J 13" 338mm 113611781D 15" 381mm . Rear SA outer 113611782 21.5" Rear "T" 69-78 113611764C 25.5" "T" to Hose SA 113611764B 31.5" 800mm 113611724J 64" 1642mm 171611739 7 ft 2174mm . MC to Rear "T" 311611741
Brake Master Cylinders
Buggy & T2 up to 7/66 211611011J Note: this one uses the screw in reservoirs T-1 up to 7/64 113611021 T-1 8/64-7/66 113611023B T-1 8/66-78 except SB 113611015BD T-1 SB 8/70-8/79 113611015BH T-2 w/servo 8/67-7/79 211611021AA T-2 8/69-7/70 211611021T T-3 8/66-8/73 311611015J
Brake Reservoirs & Misc Parts
Brake Reservoir . T-1 & SB 67-on 113 611 301L Brake Reservoir for T-2 60-67 Metal Base 211 611 3011 Brake Reservoir Cap for #2 113 611 351 Bleeder Valves T-1,2,3,4 211 611 477 Bleeder Dust Caps "Rubber" 211 611 483 Brake line "T" Metric 803 611 755 Brake Switch 2-prong 113 945 515H Brake Switch 3-prong 113 945 515G
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