drum brake upgrade? (1 Viewer)

[agent orange]

I was installing some 4runner brakes this weekend, and my fiances dad who was helping me out suggested i see if i could find some bigger wheel cylinders from some heavier duty drum brakes to take advantage of the new 1 1/16 MC. You guys know of any junkyard upgrades? Thanks.

 

[lovetoski]

The only rear brake upgrade I've heard of is to go to disc brakes. Even then, unless you run much larger wheels/tires, it's not an upgrade that's high on the list...4 runner front calipers are a significant upgrade...not so sure about a rear disk brake. Maybe others will post with their experience...

 

[Spook50]

Where did you get a 1 1/16" MC? I too have the 4Runner calipers, but the MC I got (off a Toyota pickup) is a 1" bore, as opposed to a 62's stock 7/8" bore. The larger calipers are great. Be aware though if you haven't gotten it back together yet, the wear indicator and the block of pad backing plate it's riveted to (on the outboard pads) needs to be cut off of the pads, and depending on who made your pads (mine are Hawk performance pads) for the inboard pads, the "ears" that the wear indicators are on also need to be ground down so that when you look at the pad straight on, there should be no ears on the inside part of the pad (or else they'll catch on the steering knuckle and won't be pressed against the rotor very easily when you hit the brakes).

As far as the rears, I say go ahead and do the disc upgrade. I'll be doing mine either this weekend or the next and I'll report back on how much of a difference it makes. Brakes are a big deal to me, as a safety issue, so I've done a lot of work and research on gett eh absolute best braking ability for my rig. It's a long, multi-tiered project

 

[FJ40Jim]

What is the perceived advantage to increasing the bore size of the MC and increasing the bore size of the wheel cylinder?

 

[Civil1]

Where did you get a 1 1/16" MC? I too have the 4Runner calipers, but the MC I got (off a Toyota pickup) is a 1" bore, as opposed to a 62's stock 7/8" bore. The larger calipers are great. Be aware though if you haven't gotten it back together yet, the wear indicator and the block of pad backing plate it's riveted to (on the outboard pads) needs to be cut off of the pads, and depending on who made your pads (mine are Hawk performance pads) for the inboard pads, the "ears" that the wear indicators are on also need to be ground down so that when you look at the pad straight on, there should be no ears on the inside part of the pad (or else they'll catch on the steering knuckle and won't be pressed against the rotor very easily when you hit the brakes).

As far as the rears, I say go ahead and do the disc upgrade. I'll be doing mine either this weekend or the next and I'll report back on how much of a difference it makes. Brakes are a big deal to me, as a safety issue, so I've done a lot of work and research on gett eh absolute best braking ability for my rig. It's a long, multi-tiered project

Gathering parts myself to do this. I would bet that the 1-1/16" MC came from a T-100

 

[soggy60]

The perceived advantage of going to the 4runner calipers: 4x40mm pistons rather than 2x40 and 2x 38 ( or 2x38 & 2x36) mm pistons and a larger pad area afford a better clamping force.

The larger bore MC is to reduce the pedel travel when compensating for the added volume displacment of the larger caliper pistons.

"I think" it's the larger brake pad that 'buys' the added braking power; the larger cailpers (and pistons) are tied to the larger pads and that requires the large bore MC.

 

[agent orange]

Yeah, my 1 1/16 MC came off a T-100, it was real cheap too. I was just thinking that if toyota ever made a heavier duty drum brake cylinder that i could snag one from a junkyard and put on new shoes and have a little better brakes for cheap (i know the bigger MC has the capacity to push bigger brakes).

About the wear indicators, are they the little tiny tabs that come off of the bottom of the pad? i didnt see anything sticking out from pad when looking down at it from above. The pads seated nicely up against the rotors once i got it bled, do the ears interfere after you get on the brakes?

 

[Tapage]

80 series MB cilinder fits in a 60 series .. ?

 

[agent orange]

Are you talking about a master cylinder or the one in the drum brakes i was talking about? Im pretty sure an eighty series MC would bolt up.

Anyone know how to get the brake fluid sensor hooked up again? im thinking i could go to the dealership, get a plug that fits into my T-100 MC and clip off the old sensor and put the new plug on. Would that work?

 

[Spook50]

Yeah, my 1 1/16 MC came off a T-100, it was real cheap too. I was just thinking that if toyota ever made a heavier duty drum brake cylinder that i could snag one from a junkyard and put on new shoes and have a little better brakes for cheap (i know the bigger MC has the capacity to push bigger brakes).

About the wear indicators, are they the little tiny tabs that come off of the bottom of the pad? i didnt see anything sticking out from pad when looking down at it from above. The pads seated nicely up against the rotors once i got it bled, do the ears interfere after you get on the brakes?

Being able to put more pressure against the friction surface (like it seems you're talking about with stock drums and just a larger bore MC) won't buy you more braking ability. It'll just let you lock up the brakes quicker. Now with a larger friction surface like the 4Runner calipers give you, then you have better braking ability. Here is where a larger bore MC comes in, as it (like soggy60 said) moves more fluid with a shorter stroke of the piston, ie less pedal travel.

For the wear indicators, you're right, they're the little tabs on the "bottom" of the bads. You won't see them from above. Initially they'll seat nicely against the rotors, but once you start driving it (this is what happened with me) you'll likely hear a grinding noise that could be intermittant. I traced it to the indicators on the outer pads. The section of mounting plate that it's riveted to was rubbing the hub portion of the rotor, so I just cut the whole ear off the pad, making it flush. For the inner pads, you'll notice on each pad there's a wear indicator mounted on an ear of backing plate, with another ear adjacent to it on the pad. These may not interfere with anything, but depending on who made your pads, they could. The Hawk pads that I have are a terrible fit, but they do stop my truck very well. You'll know if they're causing problems if the calipers are difficult to bolt onto the knuckle. The bolts will just BARELY line up, but not enough to thread into the knuckles. I cut those ears off of the pad as well. Next time I take my front wheels off, I'll pull a pair of pads out and take a pic to show you guys what to cut off.