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Thu Dec 10, 2009 10:47 am

I have a 67 dune buggy w/bus drop boxes on it (was a hunting buggy) I'm thinking on putting rear disc brakes on it for simplicity, but found out that T2 rear disc brakes are not available. To put rear discs on it i would have to change out the trans & axles. Is there any way to get around this? Another question is how much are the boxes slowing me down for converting it to a street/play buggy? Any suggestions?
Fred
will try to send picture when i figure out how[/img]

Thu Dec 10, 2009 12:23 pm

I use my boxes on the street and play. It's not just for hunting. I wouldn't go jumping it with them. The bus brakes are designed to stop a bus. Do you still need more for your bug?

Thu Dec 10, 2009 2:26 pm

I have been looking into putting disks on mine as well, about the only way to do it without spending a fortune would be to cut the drum down so that you had just a flange left to mount the wheel to and making a rotor adapter that the wheel studs pressed through. The caliper mount could be pretty standard like the way they mount the T1 calipers.

The other option would be machining a new hub piece and getting the stub axle spline broached into it. Then making an aluminum plate that the wheel and rotor could be bolted too. Not a cheap solution by any means.......

Thu Dec 10, 2009 3:50 pm

Thanks guys. Guess I'll have to keep thinking about it til I can find some cheap used parts or more $$s. How much will the reduction boxes slow me down anyway?

Thu Dec 10, 2009 4:10 pm

mabe this will be some help :wink:

http://www.thesamba.com/vw/archives/info/rgb_calc.php

Thu Dec 10, 2009 7:05 pm

bdkw1 wrote: I have been looking into putting disks on mine as well, about the only way to do it without spending a fortune would be to cut the drum down so that you had just a flange left to mount the wheel to and making a rotor adapter that the wheel studs pressed through. The caliper mount could be pretty standard like the way they mount the T1 calipers.

The other option would be machining a new hub piece and getting the stub axle spline broached into it. Then making an aluminum plate that the wheel and rotor could be bolted too. Not a cheap solution by any means.......

Years ago, John Johnson racing offered disc brake kits for reduction boxes. I've checked around and nobody currently offers a kit.

For a hub, you could use a late Type 3 rear hub for early reduction boxes or a 1971 or newer Bus or Vanagon rear hub for late reduction boxes.

My car is great for both off-road and the street. I have early reduction boxes with rare 1963 1/2 optional M216 reduction gears (same ratio as 1964 to 1967 standard gears) and a Der Transaxle built transmission. It has a 3:88 ring and pinion, but I don't remember what the other internal gears are.

Thu Dec 10, 2009 7:43 pm

thefladge wrote: Years ago, John Johnson racing offered disc brake kits for reduction boxes. I've checked around and nobody currently offers a kit.

For a hub, you could use a late Type 3 rear hub for early reduction boxes or a 1971 or newer Bus or Vanagon rear hub for late reduction boxes.

O'really, I'll have to look into that.

Sat Dec 12, 2009 1:51 am

couldn't you use inboard brakes run right near the trans output flanges? The downfall is the rotors stuck down a bit lower than most want the skid plates.
These Jag IRS units have them. Some Cobra kits run something like this

http://cgi.ebay.com/ebaymotors/COMPLET-JAGUAR-IRS-...33578dfbc4

Sat Dec 12, 2009 10:13 am

xirxious wrote: couldn't you use inboard brakes run right near the trans output flanges? The downfall is the rotors stuck down a bit lower than most want the skid plates.
These Jag IRS units have them. Some Cobra kits run something like this

http://cgi.ebay.com/ebaymotors/COMPLET-JAGUAR-IRS-...33578dfbc4

It's a swing axle trans. No output flange near the trans.

Sat Dec 12, 2009 11:30 am

the stock type 2 brakes on the redux boxes should be more then enough for a buggy.

Sat Dec 12, 2009 9:51 pm

I do agree that the stock drums are good enough depending on what you are doing. Are you tromping thru mud and crud, or going fast thru the dezert and getting them hot??
I have seen pix from the old days were guy's would drill small hole's in the drum's I am guessing for eithor cleanout of water/crud or an early crude way to cool them off from a raceing situation type of thing.
I would just do a complete rebuild of the brakes and try that, it will suprise you.
As far as "slowing" you down, how fast do you want to go?
You can run a smaller engine with less power (and less cash) to do the same as most other's with a big engine. Plus you have the crawl ratio far better than anyone except something with a transfercase or really small tires. I do agree disk brakes are better in most cases, I loved it when I got mine but I run at speed thru the dezert.
I would spend the $300.00 to rebuild what you have and the other grand on an engine rebuild kit and offroad light's. Just my thought's.

Mike

Sun Dec 13, 2009 1:26 am

I don't know, the brakes on mine are less than awe inspiring. With 31" tire it seems it would take about 500#'of pressure on the brake pedal to make them lock up. Admittedly the shoes are old and may need to be replaced. But still, driving on the street requires planning ahead. Panic stops are not something I'm looking forward too.

Sun Dec 13, 2009 9:39 am

The shoes may need to be adjusted. I've got bus brakes in the back with 30 inch tires, and a quick stop would put me throught the dash if I didn't have a seat belt on.

Sun Dec 13, 2009 2:51 pm

Jason C wrote: The shoes may need to be adjusted. I've got bus brakes in the back with 30 inch tires, and a quick stop would put me throught the dash if I didn't have a seat belt on.

Stock front drums? What MC are you running?

Sun Dec 13, 2009 5:12 pm

Stock front brakes and master cylinder for a 66 bug. The front has S.S. brake lines.

Sun Dec 13, 2009 6:05 pm

Jason C wrote: Stock front brakes and master cylinder for a 66 bug. The front has S.S. brake lines.

Hmm, I'm running the bus master. I wonder what the bore sizes are for the 2....... My pedal feels like I'm pushing on a brick wall so I'm thinking the bus might have the larger bore.

Sun Dec 13, 2009 7:55 pm

One of the "oldschool" budget tricks I've heard of was to run the T2 mastercylinder, but to plumb the front circuit to the rear wheels and rear circuit to the front wheels. This put more of the pressure to the larger rear tires, and helped prevent the smaller/narrower fronts from locking up on loose surfaces.

Sun Dec 13, 2009 9:17 pm

the type 2 M.C. has a 22mm bore, you could use a M.C. from an early bug ( 17mm or 19mm bore )

a larger wheel cyl. will give more pressure at the brakes & a larger master cyl. will make it harder on the peddle.

at least I think thats how it works .

Sun Dec 13, 2009 10:15 pm

I run '65 Bug brakes up front and 1963 Bus brakes in the rear. Master cylinder is a late dual circuit Bug unit.

Mine stops very quickly when everything is worling right.