16" Vanco Big Brake Kit on 15" Steelies

Yoda

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I'm planning on running 33's on 15" rims and may eventually get 35's if I get more serious into wheeling. I've come across a few old posts of people here saying that they managed to fit 15" rims over the 16" Vanco big brake kit. There was just enough clearance to make it work.

I've searched and searched but I can't seem to find which wheel they were using. Does anybody know which 15" wheel will work with the 16"Big Brake Kit?

Thanks!
 
The information is out there....for the life of me I couldn't find it though!
 
The only thing I know is generally around 4" of backspacing on an average 15" steel rim is enough to clear the 16" kit. Too many variables to know for sure.
Thank you sir!

I'll be going with 15x8's with 3.75" backspacing. I'd like aluminum rims to keep the weight down. I might have to buy an aluminum one and some steelies and see if I luck out.

@mrblaine ... One last question. I plan to get your 16" kit with the new Master Cylinder, but I also plan to get your rear disc conversion. Does that MC in the 16" kit play nice with the rear discs or do you recommend another MC? And is a different proportioning valve needed?
 
The only thing I know is generally around 4" of backspacing on an average 15" steel rim is enough to clear the 16" kit. Too many variables to know for sure.
Thank you sir!

I'll be going with 15x8's with 3.75" backspacing. I'd like aluminum rims to keep the weight down. I might have to buy an aluminum one and see if I luck out.

@mrblaine ... One last question. I plan to get your 16" kit with the new Master Cylinder, but I also plan to get your rear disc conversion. Does that MC in the 16" kit play nice with the rear discs or do you recommend another MC? And is a different proportioning valve needed?
 
I'm planning on running 33's on 15" rims and may eventually get 35's if I get more serious into wheeling. I've come across a few old posts of people here saying that they managed to fit 15" rims over the 16" Vanco big brake kit. There was just enough clearance to make it work.

I've searched and searched but I can't seem to find which wheel they were using. Does anybody know which 15" wheel will work with the 16"Big Brake Kit?

Thanks!
Just did these recently with the BBK.
https://www.trailbuiltoffroad.com/b...9/vision-manx-15x8-19?suspension=Leveling+Kit15 x 8 x 3.75" BS 35 x 12.5

Rubies & Rubicon.jpg
 
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Thank you sir!

I'll be going with 15x8's with 3.75" backspacing. I'd like aluminum rims to keep the weight down. I might have to buy an aluminum one and see if I luck out.

@mrblaine ... One last question. I plan to get your 16" kit with the new Master Cylinder, but I also plan to get your rear disc conversion. Does that MC in the 16" kit play nice with the rear discs or do you recommend another MC? And is a different proportioning valve needed?
The only 16 with a master is the Super 16 which is way too much for 33's and 35's and will not fit inside any 15" rim with more than 1" of backspacing. Get the 16" kit, your master and stock combo valve are fine.
 
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Thank you mrblaine! It's weird being given good advice and not being upsold to some giant break kit just because. Can't wait!
 
Thank you mrblaine! It's weird being given good advice and not being upsold to some giant break kit just because. Can't wait!
That isn't in either of our best interests. My biggest problem child customers are the ones who don't listen. Oddly, and for reasons I have yet to fathom or understand, it is almost always a rig on 33's who wants to run a brake kit that works for 37's. Then the bullshit starts because they are very hard to keep broken in then they want a shitty pad to stop the effectiveness, blah blah blah.

The overwhelming majority of the time, a set of our stock front pads will work just fine and then some for 33's. Use some premium rotors if you don't have them.
 
Well....the entire brake system is shot. It's been sitting for forever and is all rusted frozen. It needs new everything and for the moment I'm going to rock 32's or 33's but when those wear out I'll upgrade the suspension further and go to 35's.

I only want to do this once and the regular 16" kit sounds like a winner. Agree?
 
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Well....the entire brake system is shot. It's been sitting for forever and is all rusted frozen. It needs new everything and for the moment I'm going to rock 32's or 33's but when those wear out I'll upgrade the suspension further and go to 35's.

I only want to do this once and the regular 16" kit sounds like a winner. Agree?
Yes.
 
I can say I am running the 15" BBK and 35's and mine now stop great compared to stock. Not really sure how much better the 16" kit are over the 15"
 
I can say I am running the 15" BBK and 35's and mine now stop great compared to stock. Not really sure how much better the 16" kit are over the 15"
I just purchased the 16" BMB kit (not installed yet). The rotor diameter is 12" (vs 11" stock) which is a 9% increase in radius and therefore the leverage the caliper has on the system. So I'm guessing the 16" kit should have 9% more power than the 15" with the same caliper & master cylinder? But, I'd bet that won't translate into that much change in stopping distance.
 
I just purchased the 16" BMB kit (not installed yet). The rotor diameter is 12" (vs 11" stock) which is a 9% increase in radius and therefore the leverage the caliper has on the system. So I'm guessing the 16" kit should have 9% more power than the 15" with the same caliper & master cylinder? But, I'd bet that won't translate into that much change in stopping distance.
I am not brake expert but is it more of the " 48mm dual piston Calipers " and brake pads compared to the stock calipers and not so much the size of the rotors ? 🤷‍♂️
 
Yes. Compared to stock, I agree. I was comparing the BMB 15" and 16" kits which use the same caliper.
 
More math: other things being equal, hydraulic pressure is proportional to piston area. The stock single piston diameter is 66mm so area is 325 mm sq. The BMB calipers have two 48mm pistons for 473 mm sq. So 46% more power than stock with an 11" rotor and 55% more power than stock with a 12" rotor?

Edit: WRONG. (lesson: don't rush)

area of circle=3.14 x Radius squared:
Stock caliper/66mm piston x1: 33x33x3.14= 3419 sq.mm (about 5.3 sq.in)
BMB caliper/2x 48mm pistons: 24x24x3.14x2= 3617 sqmm (about 5.6 sq.in) 6% greater area.
 
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More math: other things being equal, hydraulic pressure is proportional to piston area. The stock single piston diameter is 66mm so area is 325 mm sq. The BMB calipers have two 48mm pistons for 473 mm sq. So 46% more power than stock with an 11" rotor and 55% more power than stock with a 12" rotor?
The stock piston is 5.22 square inches, the dual 48's are 5.60 square inches. Not that much of a difference. The piston area is only a small part of it.