Brake upgrades: rear handbrake options...

[Mezzanine]

Hello all!
In all the saabs I have owned with front e-brakes, I have yet to make a set work right for more than a month before they pull unevenly or don't work at all... What good is an e-brake if they don't work? Perfect opportunity for a brake upgrade, right? I am slowly gathering the components together to convert my '85 900 notchback brakes over to wilwoods... I found a set of vented rotor hubs, and will be ordering the calipers and new rotors soon. I am still a little stuck on the rear caliper dilemma. As this will be a road-going car, I still need a handbrake, but I haven't come up with a good solution. I have already robbed a parts car of it's rear handbrake cables and kit, so I am all set there. There is lots of talk on here about Volvo 240 calipers for the rear, but I haven't been able to discern just which volvo calipers to try. Any particular year? I am a little confused on how it would work out because according to Wikipedia: "Rear: twin piston calipers utilizing solid rotors and integral parking brake drums." Also, on the "cars" section, it says the rally car has a hydraulic rear handbrake... I tried to find a set locally, or even a photo or diagram online of how the rear volvo brakes work without success. Sounds to me like the little drum brake is independent of the caliper itself. I think the 240 caliper is right out for me. I suppose I could get REALLY creative and try to mount something like this on there with some elaborate bracketry: http://www.jegs.com/p/Wilwood/Wilwood-Mechanical-Parking-Brake-Spot-Calipers/757779/10002/-1.
I tried to find superlites with the mechanical handbrake option, but can't actually find any for sale... Lots of talk about them on various forums, but can't actually find any!


So to summarize, I need a rear mechanical handbrake. I don't want to go hydraulic as I wouldn't expect a hydraulic brake to hold for long in a parking application. I also need a rear caliper with a larger bore to balance out the larger wilwood caliper bore. Any words of wisdom for me?

Regards,

Craig R.

[Jordan]

If you do a search for 'rear wilwood' you can find the post that mentions a UK spec rear powerlite model with rear ebrake option. I'm not sure if you can find them at a retailer in the U.S. (ebay?) but that would be the easiest solution if you could get your hands on a set of Luke's adapters. This is what is sitting on my office desk... just the standard powerlites + adapter (I'm going hydraulic).

As for 'not being able to hold'.. worst case scenario, leave it in gear? I don't see why they wouldn't be able to hold enough pressure to hold a parked car unless something is really wrong with the system.

[SwedeSport]

What about doing a hydraulic rear handbrake, but use a linelock valve like on the drag race cars. Or even setup the lever so it still ratchets up into place, but figure out a way to defeat the ratchet for actual racing use???? Seems this would be much simpler.

[Jordan]

The hydraulic e-brake I got (ebay maybe 100 bucks?) has a ratcheting mechanism that can be disabled for racing or enabled for locking (same flip mechanism on rally car 2.0). Very simple but proven effective.

[99Super]

Same problem here. I have the 86-87 Vented brakes on my 99T and want to upgrade to the Wilwoods in the front, but that leaves me w/out parking brakes. I have a set of Luke's Wilwood caliper adapters for the rear, but that doesn't help me either. A line-lock only works for parking...

The rear rotors on the 99 though the 87 900 were the same as the fronts on the <75 cars. Those cars have the e-brakes as a drum using the inside of the rotor, just like the rear of the Volvo 240 and M-B 123 Chassis cars, some Porsches as well. Could we adapt one of those backing plates and drum brake sets to our existing rotors? Maybe from a 99 even?
The Wilwood Superlites also work like this.

The aircooled VW disc conversion kit's I've seen use a mid-80's Toyota Celica rear caliper w/ cable e-brake. What about adapting an existing stock caliper?

Here's an elegant solution, but at a hefty price,
http://www.wilwood.com/CaliperList.aspx ... %20P-Brake

john

[Mezzanine]

I hear you guys about the hydraulic options, but do you really expect it to hold pressure overnight? I suppose with a line lock it might, but I would be surprised if a ratcheting hand brake holding pressure by the master alone would hold for long. Do line lockers require constant voltage, or is it 12v to open, 12v to close sort of affair? I wouldn't want to park my car knowing it is secure at the expense of a dead battery.
John, I would love to find a similar caliper (like the celica you mention) and modify as needed, and this is the route I anticipate heading. You probably have a stash of old style 99 calipers lying around, right? That sounds like a very good, very plausible idea except for one thing- caliper bore. It will still be a small bore caliper! If we go Wilwoods in the front, we will need to increase the rears by ~50% to even it out if I understand correctly. I think I need to get mounting measurements, disk offset, and rotor size and head to the junk yard. Maybe that volvo 240 caliper will do it?


C

[99Super]

Well, if you need a larger bore, the 240 or M-B front caliper should work, but it is the same style as the rears we currently use. Dual piston w/ no e-brake. The e-brake works on a drum internal to the rear rotor. I think I'm going to have a look at maybe installing a early 99 or 2nd gen 900 backing plate and trying the mechanical drum thing. I'm really wishing I hadn't just disposed of a pair of early 99 axles I had around.

I think I was wrong about the Celica caliper. Nissan 240 and Maxima calipers (among others) are hydraulic w/ a mechanical e-brake.

So, what diameter bores do we need in the rear if we go to the Wilwoods in the front?

john

[Luke]

My hydraulic handbrake holds for weeks, try it !

I hear you guys about the hydraulic options, but do you really expect it to hold pressure overnight? I suppose with a line lock it might, but I would be surprised if a ratcheting hand brake holding pressure by the master alone would hold for long. Do line lockers require constant voltage, or is it 12v to open, 12v to close sort of affair? I wouldn't want to park my car knowing it is secure at the expense of a dead battery.
John, I would love to find a similar caliper (like the celica you mention) and modify as needed, and this is the route I anticipate heading. You probably have a stash of old style 99 calipers lying around, right? That sounds like a very good, very plausible idea except for one thing- caliper bore. It will still be a small bore caliper! If we go Wilwoods in the front, we will need to increase the rears by ~50% to even it out if I understand correctly. I think I need to get mounting measurements, disk offset, and rotor size and head to the junk yard. Maybe that volvo 240 caliper will do it?


C

[Mezzanine]

My hydraulic handbrake holds for weeks, try it !

Call me a push-over, but that is exactly the affirmation I hoped someone would say! So with that in mind, I need to track down a crusty junkyard volvo to get a caliper to mock up with...
I have a handbrake ass'y, so I can get a master modified and mounted in advance. This is all too exciting! Suggestions on what master to use? 5/8" bore ok?


C

[paulh]

And if you're really scared of it letting loose, just get yourself something like this puppy:

http://cgi.ebay.com/ebaymotors/02-BMW-3 ... ccessories

and you'll be all set for long term hillside parking.

Paul

[Geoff]

Don't the Volvo front calipers need welding and re-drilling to get the tabs to fit?

If you're into junkyarding, the word around the campfire is that RX-7 front calipers will bolt up and fit the front of a -'87 99/C900. They're 4 piston and made from aluminum. No idea on bores or wheel interference, I've never tried it.

[SwedeSport]

You could always just carry a brick around with you. Not only does it keep your car from rolling away, it also comes in handy when you're being tailgated.

[Luke]

Heard the same thing before, but the I tried it and not even close to fitting, someone must have started this rumor and it got propogated. They are nice calipers though.

Don't the Volvo front calipers need welding and re-drilling to get the tabs to fit?

If you're into junkyarding, the word around the campfire is that RX-7 front calipers will bolt up and fit the front of a -'87 99/C900. They're 4 piston and made from aluminum. No idea on bores or wheel interference, I've never tried it.

[Geoff]

The RX-7 ones must need some welding and drilling too :-P
I know where the rumor started but he will not be named....

[99Super]

I was thinking that if we could find an appropriately sized, reasonably common, Asian rear brake w/ cable e-brake, we do a group buy and have SAABRally make a batch of adapters like they did for the Wilwood rear caliper. What about for a 9000 rear brake caliper?