worth going from 10" brakes to 11"?

my 69 v6 appears to have 10" drums. is it worth going to the trouble to convert to 11" brakes? i know that 9" to 11" is a no brainer. (perfect for those of us with little or no brains left)

 

The 71 models are self adjusting.

 

they've got a star wheel inside that i had to back off when i was going to try to remove the drums. ( i stopped before i removed em tho')

 

Some older wheels won't clear the 11" drums. That happened to one of my buddies with his '70. His old Blackjacks wouldn't fit over the 11" ers.

 

I have 10" on the flatty and no issues stopping unless they are wet. I've locked all 4 tires in an emergency stop, and slowed as quickly as so-cal traffic requires without issue - which can be pretty quick. That said my new front Dana 30 has disks.

 

Really? How does one know? Isn't there some additional hardware inside the backing plate? (If so I haven't seen it on my'71 ) Although I do try to jam on the brakes in reverse to set 'em.....not sure if it helps.

Overall I'm happy with the 10" brakes as long as I can plan my stops ahead of time.

 

Some self-adjusters have cables (Bendix), some have arms. Inside the drum, there's a mechanism that pulls on the cable or arm when you brake in reverse and lifts a pawl that turns the star wheel. On manual adjust, the star wheel is held at its fixed adjustment by a spring. Should be obvious if you have the drums off.

The contact area increases by approx. 10% when you go from 10" to 11" - I always felt that the 11" power brakes were fine unless they were wet. The real stopping power comes from the tire-to-pavement contact, so if you feel that you can now always lock up the tires, and the braking is always controllable, then there's no need to upgrade. Certainly the larger the drums are, the less they will fade on long downhills.

Personally, I'd think about disks on the front and leave the 10" rears, if you can get parts for them. Most of the braking is done by the fronts anyway. Not sure that it's such a bargain to upgrade a 27, but that's up to you.

 

Lynn - I was thinking about your project the other day (when you drilled the drums). Didn't you do a write up about it? How in the world did you lay out all the holes?

 

When I went from stock to the ten inch setup, the first thing I was told was to take out the self adjusting mechanism. The thinking was that, in the event you must back down a long hill, you may eventually lock them up. Might take time, but the cumulative effect is potentially there. Before they lock up, they would certainly be dragging, which would probably go unnoticed for some time. I'd rather take care of my own maintenance than have some questionable piece of hardware do it for me. Having said all that, the ten inch setup has always worked well for me, but then I also run stock tires, which is a huge factor. More rolling mass is harder to stop.

 

Sounds like hooey to me ... the amount the adjustment arm travels when you back up is determined by the distance between the adjuster and the brake shoes. As you tighten the adjuster, the movement of the arm becomes smaller and smaller until it's no longer enough to climb over the next peak on the star wheel. At this point the adjustment stops, no matter how much backing up you do.

IMO self-adjusters are great as long as your backing plates aren't worn out. If you have grooves worn in the backing plates where the shoes ride, the adjusters will stop working.

Nothing wrong with manually adjusting the brakes, except that it's another maintenance task.

 

I'm really struggling with this decision too... 11" or discs... I *thought* the discs were a breeze until I started reading the write-ups. There are a lot of mods associated with it, at least more than I thought.

So, I changed my mind and decided that I'd just go with 11" drums and be done with it. But, now I'm starting to wonder. The 10's that I have now function properly - IMO - but they are non-existant when wet, and they always pull to one side or the other. I know that discs would solve the problem, and I thought 11" drums would too. But now I'm not so sure.

I already have the caliper mounting brackets, just need the rotors and other small parts. But I HATE messing with the MC (I assume you have to pluck the prop valve out of one of the ports?)

 

Tim, it may well be hooey; dunno, I was only about 22 at the time. Right between knowing everything, and realizing I don't know squat. Never missed not having self adjusting brakes tho.

 

Mine are stock 10" drums and I just don't have any problems. I drove it all week last week in the rain. I got wet so I assume the brakes did too. No problem.