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Brakes - Make better or start over?

Corvette master, with should be 1.125?
I would bet your mc is janky... if you can slowly push the pedal to the floor with the engine off, it seems to me that the piston in the mc is bypassing. I could be wrong though, and maybe the booster is allowing this, but i would think the mc should build pressure and lock the pedal in at some point.
 
I would bet your mc is janky... if you can slowly push the pedal to the floor with the engine off, it seems to me that the piston in the mc is bypassing. I could be wrong though, and maybe the booster is allowing this, but i would think the mc should build pressure and lock the pedal in at some point.
I'd tend to agree.

Also, you could swap to a bigger master, but I don't think that would be the solution.
 
I'll take a look at it when I have some time and compare it to the version of Billavista's calculator that I modified a while back. Thanks for sharing!

'84 Bronco II - you had a chance to review?


I've been dragging my feet on ordering a hydroboost setup, apparently gutters are more importanter than hydroboost.
 
Im just beyond irritated with it. its a brake setup that people have run for ages, it should be as simple as use this booster/master
 
Im just beyond irritated with it. its a brake setup that people have run for ages, it should be as simple as use this booster/master
Why won't you use a hydroboost then ?
It will work.
 
So while we're on the subject of master cylinders...

How far back does the mounting pattern used on the GM hydrboost go? Can I fit a master cylinder off some ancient drum brake POS of that's what it takes to get a master cylinder small enough for my ancient drum brake POS application?
 
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I would bet your mc is janky... if you can slowly push the pedal to the floor with the engine off, it seems to me that the piston in the mc is bypassing. I could be wrong though, and maybe the booster is allowing this, but i would think the mc should build pressure and lock the pedal in at some point.
It's gotta be the master. Booster can't do that. There's no space for stuff to travel. If the brake calipers were a problem he'd have a puddle.
 
'84 Bronco II - you had a chance to review?


I've been dragging my feet on ordering a hydroboost setup, apparently gutters are more importanter than hydroboost.

The calculations look good, but your version of the calculator lost some functionality and some useful notes from the original calculator.

The biggest problems are that you cannot enter caliper/rotor information for rotors you don't have listed (unless you add an entry in the other sheets), the coefficient of friction for the tires is locked in at 1 (very conservative for our use case), and there is no way to try out the effects of more/less aggressive pad compounds (your version of the calculator ties it to caliper choice).

Other than that I like the layout a lot better than the original Billavista calculator. Someone needs to take the time to update the calculator with all the common caliper and rotor choices for off road use, but that is a huge pain in the ass and being able to manually enter that information in the user inputs would be nice. Where were you finding rotor weights?
 
I'm half decent at excel but don't have the data collected.

If someone can compile the data I don't mind updating the calc
 
Why won't you use a hydroboost then ?
It will work.
quite honestly price.....but maybe Im being cheap. I can get a JY GM hydro boost that isnt ported for liek $100. But also was trying to trouble shoot my current setup. I feel like it should work better than it does, hence trying to determine the cause being the booster or MC.

But even with the BKOR setup, they say it might not run bigger calipers, compared to the little wilwood ones.
 
But also was trying to trouble shoot my current setup. I feel like it should work better than it does, hence trying to determine the cause being the booster or MC.
Why don't you change your booster or MC?
Asking questions here isn't troubleshooting.

FYI, I have put the same MC you have on a rig with Ford Kingpin 60 dual piston calipers up front and JB7 single piston calipers out back with excellent success.

Also, the wilwood MC is aluminum. If you dry stroked it before putting fluid in it, you probably scored it and it's bad.
 
The calculations look good, but your version of the calculator lost some functionality and some useful notes from the original calculator.

The biggest problems are that you cannot enter caliper/rotor information for rotors you don't have listed (unless you add an entry in the other sheets), the coefficient of friction for the tires is locked in at 1 (very conservative for our use case), and there is no way to try out the effects of more/less aggressive pad compounds (your version of the calculator ties it to caliper choice).

Other than that I like the layout a lot better than the original Billavista calculator. Someone needs to take the time to update the calculator with all the common caliper and rotor choices for off road use, but that is a huge pain in the ass and being able to manually enter that information in the user inputs would be nice. Where were you finding rotor weights?

Throw me some specifics on useful notes or lost functionality and I could put back in. I tried to make some of them notes if you hover over a cell. I tried to make it where you don't have to transfer data from one cell to another, otherwise I tried to keep it there; but I admit I did this 2 years ago and recently blew the dust off it, so some of it is foggy.

Could easily separate pad compound and wheel coeff to make it separate.

Rotor weights are off napa. Napa generally provides more data on rotors & calipers. I made the rotors and calipers as lookups and easy to add data as I agree, looking up the data has been a PITA. The ones included are the ones I've looked at. I'm sure there's plenty more common parts.

I appreciate the feedback.
 
How long is the bustedknucle brake pedal?

If you still need that measurement I can get it for you tomorrow - got the one that came with mine in a box. Think they have an image showing all specs on their site...
 
Those running hydro boost, if you stall or have a dead engine, how well do the brakes work?
Fine for me. But yeah you gotta push the pedal hard.

Remeber there is an accumulator so you get 2 or 3 assisted brake applications with the engine off before it fades off.

I have hydro boost and I recently had the engine stall. I was able to stop, but can’t say it was easy. When you say “2 or 3 assisted” , does that mean it should feel the same as engine running for those couple times? If so, something is wrong with mine. (Brakes are great when engine is running) Makes me scared to think it would be like after the accumulator is done.
 
Accumulator assist isn't as good as the full assist from the hydraulic power.
 
I battled crap brakes for a long time on
My first buggy and figured out what I did wrong when I was scrapping it for a new one. The rear hardline was going above the master for a bit, trapping air.
 
I ordered up the remote hydroboost system from BKOR at Thanksgiving and it arrived a few days ago. I grabbed a hydroboost master cylinder from a 2002 Chevy Avalanche 1500 since it has 1.5" bore (common to 2007 Superduty) and has SAE fittings.

Quick mockup of the remote unit. It about 22.5" long and I hope to fit between my seat and fuel cell. I guess we will see in the coming weeks.

One thing I did note that was the master was spaced off the booster by a hair. I'm thinking I could cut a shim to adjust the spacing rather than remaking the pushrod. I think a 0.040" shim would do the trick.
 

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Is a ported HB setup absolutely necessary? I have a stock unit laying here but am apprehensive to use it. I watched the BK tech videos on the HB setup and came away with a ported unit being optimal. Does anyone have any experience with running a stock unit? The setup is a Howe TC pump to a PSC 2.5x8.75 ram.
 
Give it a shot and report back. If you have the parts, the worst that happens is you dislike and have to go to a ported unit.
 
None of my friends have used a ported unit and none have had issues. The only one that had any issue was the one who ran a remote mounted unit and had issues with air between the pedal master and slave that's mounted under the floor in the belly of the buggy.
 
Give it a shot and report back. If you have the parts, the worst that happens is you dislike and have to go to a ported unit.

Good point.

None of my friends have used a ported unit and none have had issues. The only one that had any issue was the one who ran a remote mounted unit and had issues with air between the pedal master and slave that's mounted under the floor in the belly of the buggy.

That is encouraging. :beer:
 
Is a ported HB setup absolutely necessary? I have a stock unit laying here but am apprehensive to use it. I watched the BK tech videos on the HB setup and came away with a ported unit being optimal. Does anyone have any experience with running a stock unit? The setup is a Howe TC pump to a PSC 2.5x8.75 ram.

I've installed both.
Non-ported runs a lot warmer. But they work the same.
 
Update to close out the thread. I ended up installing Honda Accord iBooster with a custom pedal box I built for my buggy. I went from stock super duty front calipers and rotors to Howe 2.625" calipers on 1999 E350 rotors, and the rear went from Chevy 1/2-ton calipers to 2009 Ford Flex calipers with the same 2001 3/4-ton chevy rear rotors.
 
How has the installation of all new components transformed the performance of your buggy's braking system? Have you noticed any significant improvements in terms of responsiveness, stopping power, and overall driving experience since completing these modifications?
 
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