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Jehannum
 
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90% of your braking force is generated at the front anyway, so focus your effort there.

I like EBC redstuff. Had Pagid blues on the front of my Z32, and they were on par with the Hawk HP+s that I run now, at like 4x the cost. I run EBC reds on the Datto (which runs Toyota 4 piston calipers up front).

edit: honestly, you could go down and buy Raybestos and be fine. You don't track your car, so dumping money into race brake pads is foolish. Race pads require repeated, frequent, hard use to work well, and you're just commuting, not hauling it down for the hairpin.
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1992 300ZX: Not stock, 433 RWHP
1971 240Z: Toyota front brakes, 123 RWHP
1967 Pontiac GTO: not stock.

Last edited by Jehannum; 10-08-2014 at 02:40 PM..
Old 10-08-2014, 02:32 PM Jehannum is offline  
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RazorWind
 
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Quote:
Originally Posted by GhEttOrAiD View Post
I would think so too, but the pagids will be tremendously better performing! (as opposed to the worse-than-stock hawks)

OEM is something to consider, but like... the dust they put off is LEGENDARILY bad.

SO bad.

Yeah, the stock pads on my E46 make an unbelievable amount of dust, too.

I'd question whether you need, or can even realistically use, all that extra performance that a street/track compromise pad offers. I know, I know, you drive "like a badass," but the limiting factor in your car's ability to stop under typical road conditions is not any part of the brake system, but the tires. Unless you're also running R-compounds every day, you're better off with the stock ones. Save your money on the fancy-schmancy pads, and get some stainless lines, and I bet dollars to donuts you'll be happier.
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Old 10-08-2014, 02:34 PM RazorWind is offline  
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lollersk8s
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Quote:
Originally Posted by Jehannum View Post
90% of your braking force is generated at the front anyway, so focus your effort there.

I like EBC redstuff. Had Pagid blues on the front of my Z32, and they were on par with the Hawk HP+s that I run now, at like 4x the cost. I run EBC reds on the Datto (which runs Toyota 4 piston calipers up front).

Hmm, I don't know about that actually. traditionally the generic figure is "80% front" but with cars that have 50/50 weight distro I would guess it's more even than that. It can all be calculated given the piston sizes, line pressure and friction area as such:

http://www.m3forum.net/m3forum/showt...p?p=1065614092

Quote:
Front Caliper Brake Torque Calculation:
Equation 4:
60 mm / 2 = 30 mm = rpiston

Equation 6:
2 * 3.141592 * 30 mm2 = 5655 mm2 = 56.55 cm2 = 8.77 in2 = Atotal

Equation 4:
345 mm / 2 = 172.5 mm = rrotor

Equation 10:
172.5 mm - (61 mm / 2) = 142 mm = 5.59 in = Reffective

Equation 5:
591 PSI * 8.77 in2 * 5.59 in * 0.36 = 10430 in•lb / 12 in = 869 ft•lbs = T{f}

Rear Caliper Brake Torque Calculation:
Equation 4:
46 mm / 2 = 23 mm = rpiston

Equation 6:
2 * 3.141592 * 23 mm2 = 3324 mm2 = 33.24 cm2 = 5.15 in2 = Atotal

Equation 4:
328 mm / 2 = 164 mm = rrotor

Equation 10:
164 mm - (54 mm / 2) = 137 mm = 5.39 in = Reffective

Equation 5:
764 PSI * 5.15 in2 * 5.39 in * 0.36 = 7633 in•lb / 12 in = 636 ft•lbs = T{r}
It's been done for a number of brake part combos, and the chart looks like this:

If you notice the OEM e46 M3 brake bias is about 60/40. So i think it's a gross oversimplification to say "90% is front" unless you're talking about a custom application on a FWD or something otherwise the ABS would go off on the rears every time an e46 driver applied the brakes, given the proportions of everything. Feel free to correct me of course.

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Old 10-08-2014, 02:42 PM lollersk8s is offline  
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Jehannum
 
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Originally Posted by lollersk8s View Post
I'd liek to talk about this actually. traditionally the generic figure is 80%, but with cars that have 50/50 weight distro I would guess it's more even than that. It can all be calculated given the piston sizes, and friction area as such:

http://www.m3forum.net/m3forum/showt...p?p=1065614092



It's been done for a number of brake parts, and the chart looks like this:

(If you notice the OEM e46 M3 brake bias is about 60/40)




So i think it's a gross oversimplification to say "90% is front" unless you're talking about a custom application on a FWD or something otherwise the ABS would go off on the rears every time an e46 driver applied the brakes, given the proportions of everything. Feel free to correct me of course.

Yes, what I said is a simplification. The pads he's looking at buying won't change coefficient of friction substantially.
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1992 300ZX: Not stock, 433 RWHP
1971 240Z: Toyota front brakes, 123 RWHP
1967 Pontiac GTO: not stock.
Old 10-08-2014, 02:45 PM Jehannum is offline  
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lollersk8s
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Originally Posted by Jehannum View Post
You've got bias down, but that is only tangentially related to braking force. That has a lot more to do with the size of the pad and rotor combination than it does the static fluid distribution.

Take a look at the math in the thread, line pressure is part of it. Weight transfer is the only thing that i can't see in there, but we know the static distro so there's no way the front is getting "90%" even under panic braking. I would guess, given everything that it is in fact around 60/40 or maybe 70/30 in extreme cases due to weight transfer. The point is that you can't ignore the rears on a well designed performance vehicle, it's all part of a carefully balanced system.
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Old 10-08-2014, 02:51 PM lollersk8s is offline  
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Quote:
Originally Posted by Jehannum View Post
Yes, what I said is a simplification. The pads he's looking at buying won't change coefficient of friction substantially.



Gotcha
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Old 10-08-2014, 02:52 PM lollersk8s is offline  
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Jehannum
 
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Originally Posted by lollersk8s View Post
Take a look at the math in the thread, line pressure is part of it. Weight transfer is the only thing that i can't see in there, but we know the static distro so there's no way the front is getting "90%" even under panic braking. I would guess, given everything that it is in fact around 60/40 or maybe 70/30 in extreme cases due to weight transfer. The point is that you can't ignore the rears on a well designed performance vehicle, it's all part of a carefully balanced system.

Yeah, that thread is an example of death by overanalysis. Having the brake torque ratio is still only tangential to performance. You still have to take into account the rotating mass at each corner, the weight transfer to the front, and the available traction.

There's a reason why they run eensy-weensy little two piston calipers out back on 10" rotors, while they run 13" rotors with four piston calipers up front.
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1992 300ZX: Not stock, 433 RWHP
1971 240Z: Toyota front brakes, 123 RWHP
1967 Pontiac GTO: not stock.
Old 10-08-2014, 02:59 PM Jehannum is offline  
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lollersk8s
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I want to watch a video with all this in motion using pressure pads and a 4 wheel dyno or something. But i think we can safely say it's somewhere between 60 and 90, being closer to 60 in good cars, and closer to 90 in pleb FWDs
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Old 10-08-2014, 03:17 PM lollersk8s is offline  
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GhEttOrAiD
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I *will* track the car as soon as I have the rear chassis/subframe bushings and metal reinforcements installed...

Pagid's marketing claims that these pads are meant to serve double duty... But I read a tidbit somewhere (paraphrased) while on the shitter a while ago.

"using race pads softly for light duty use (stop n go traffic) will cause rotors to glaze"

Maybe I'll just go with the stoptechs as razor suggested... that's an awfully good price, and I can always switch to unobtainium $500 extra squealy fagpads AFTER I discover I don't have enough stopping power. Plus I have to consider the health/longevity of my rotors I guess, to a certain extent...

I'm also tempted to give the pads another bedding-in... really quick, use part of my lunch break...
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Last edited by GhEttOrAiD; 10-08-2014 at 03:27 PM..
Old 10-08-2014, 03:19 PM GhEttOrAiD is offline  
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Jehannum
 
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Quote:
Originally Posted by lollersk8s View Post
I want to watch a video with all this in motion using pressure pads and a 4 wheel dyno or something. But i think we can safely say it's somewhere between 60 and 90, being closer to 60 in good cars, and closer to 90 in pleb FWDs

Possibly true. I'd bet on a car with a fat pig-iron straight 6 up front, it's probably closer to 75%.

In any case, it would be relatively trivial to instrument. Just measure the suspension travel at each corner, and you'll know how much weight is transferred.
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Your powers are useless! I'm wearing my tin foil underwear!

1992 300ZX: Not stock, 433 RWHP
1971 240Z: Toyota front brakes, 123 RWHP
1967 Pontiac GTO: not stock.
Old 10-08-2014, 03:20 PM Jehannum is offline  
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lollersk8s
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Quote:
Originally Posted by GhEttOrAiD View Post
I *will* track the car as soon as I have the rear chassis/subframe bushings and metal reinforcements installed...

Pagid's marketing claims that these pads are meant to serve double duty... But I read a tidbit somewhere (paraphrased) while on the shitter a while ago

"using race pads softly for light duty use (stop n go traffic) will cause rotors to glaze"

I'm also tempted to give the pads another bedding-in... really quick, use part of my lunch break...

Go with what the manufacturer says, i think that's a wives tale. Glazing is easy to remove, just stomp the brakes a few times from 65-30, but don't stop afterwards. Glazing happens when the hot pad just sits there against the scolding rotor, for instance at a stop light after VERY hard braking.

Light braking doesn't generate enough heat to glaze afaik, sounds like to me.
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Old 10-08-2014, 03:22 PM lollersk8s is offline  
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Jehannum
 
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Quote:
Originally Posted by GhEttOrAiD View Post
I *will* track the car as soon as I have the rear chassis/subframe bushings and metal reinforcements installed...

Pagid's marketing claims that these pads are meant to serve double duty... But I read a tidbit somewhere (paraphrased) while on the shitter a while ago

"using race pads softly for light duty use (stop n go traffic) will cause rotors to glaze"

I'm also tempted to give the pads another bedding-in... really quick, use part of my lunch break...

Will you be out running dozens of laps around willow springs? The stock system is good enough to hold up to HPDE.
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Your powers are useless! I'm wearing my tin foil underwear!

1992 300ZX: Not stock, 433 RWHP
1971 240Z: Toyota front brakes, 123 RWHP
1967 Pontiac GTO: not stock.
Old 10-08-2014, 03:23 PM Jehannum is offline  
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lollersk8s
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100% front


+ YouTube Video
ERROR: If you can see this, then YouTube is down or you don't have Flash installed.
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Old 10-08-2014, 03:26 PM lollersk8s is offline  
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Jehannum
 
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100% front


+ YouTube Video
ERROR: If you can see this, then YouTube is down or you don't have Flash installed.

Bugger!

+ YouTube Video
ERROR: If you can see this, then YouTube is down or you don't have Flash installed.
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Your powers are useless! I'm wearing my tin foil underwear!

1992 300ZX: Not stock, 433 RWHP
1971 240Z: Toyota front brakes, 123 RWHP
1967 Pontiac GTO: not stock.
Old 10-08-2014, 03:37 PM Jehannum is offline  
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coworker blew it, rear ended somebody in his white 330

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