Soarer Central: Archive through November 15, 2010

Soarer Central Brakes Supra brakes to soarer Archive through November 15, 2010

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Nathan Richardson
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Thursday, November 04, 2010 - 10:41 pm, by: Nathan Richardson (Richtheblack)

Clayton Carlyle wrote on Thursday, November 04, 2010 - 07:51 pm:
Nathan, yeah I think I'm sold on the V500. I like the idea of easy tuning & 8 injector outlets.

Yup, that and it is plug and play, dual MAPs and and there are plenty of Aux ports left over to run other stuff.

Mike Beck wrote on Thursday, November 04, 2010 - 08:04 pm:
Actually after reading up, I think Damian is on the right track with what he says. It seems brake bias is also overlooked when it comes to upgrading.

Yes, I too think Damian has brought a really important consideration to our attention but the math still doesn't make sense to me.

I agree, brake bias is something often over looked but I don't think this is what is being debated here.

I can not make sense of the numbers used in the example from this site http://www.scirocco.org/faq/brakes/pulpfriction/pfpage1.html

"In order to calculate the amount of clamping force generated in the caliper, the incoming pressure is multiplied by the area of the caliper piston. In our example, the 558 psi that had been generated at the master cylinder has traveled through the brake pipes and lines and is pushing against two 1.5-inch pistons per caliper. Therefore, the effective area of the caliper will be equal to two times the area of a single 1.5-inch piston. Working the numbers reveals that 558 psi will generate 2068 pounds of clamp load
[558 psi x (1.84 in. x 1.84 in.) x 2]."

No matter how I crunch the numbers they have given, I can not get the answer they have in their example and they correctly state "the incoming pressure is multiplied by the area of the caliper piston" but there is no mention of "Pi" in their equation?

So my understanding of what they say (ignoring their formula):
Input pressure x piston area(Pi r Sq or Pi d) x number of pistons = total output pressure.

I might be way off the mark here but I would think based on the above, using arbitrary input pressure of 100psi:

Soarer 2 pots: 100psi x (Pi x 1.748in) x 2 = 1098.3lbs

Supra 4 pots: 100psi x (Pi x 1.685in) x 4 =
2117.4lbs

The site also states;
"The rotor output force is equal to the clamp force multiplied by the coefficient of friction (which is then doubled because of the "floating" design of the caliper)"

Am I missing something? Why does a floating design double the friction coefficient? To me this suggests that you get something for nothing. Almost like perpetual motion!

I'm not trying to prove anyone wrong here, I just can't comprehend what is being said and I am the sort of person who needs to understand what doesn't make sense (to me).

Damian Ware wrote on Thursday, November 04, 2010 - 09:54 pm:
The calculation is based on the area of the pistons per side of the caliper.

For a fixed caliper such as 4 pot supras there is 2 pots per side to apply force from both directions. The clamping force is only calculated for one side so the area is of just 2 pots.

For a floating caliper such as the stock 2 pots the area is just the 2 pots as the caliper by design applies force from both directions but only requires pistons on one side.

My point exactly, it doesnt make sense! Just because we are talking about brake calipers doesn't obsolve us from hydrodynamics.

Damian Ware wrote on Thursday, November 04, 2010 - 09:54 pm:
Busy night but if you need further clarification I can provide details tomorrow

Please do, I am going to be up all night trying to get my head around this.

Cheers

Nathan Richardson
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Thursday, November 04, 2010 - 10:51 pm, by: Nathan Richardson (Richtheblack)

Sebastian Grant wrote on Thursday, November 04, 2010 - 10:38 pm:
Thanks for the info David, I guess I'll be sticking to my standard brakes then

David?

Please don't confuse me any further hahaha!!!!

Warren Moore
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Thursday, November 04, 2010 - 11:07 pm, by: Warren Moore (Warreng)

Allan, where u from? gary mcmillan is pretty much around the corner from my place haha

Ben Lipman
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Thursday, November 04, 2010 - 11:36 pm, by: Ben Lipman (Ben12a)

I don't give a damn about the maths. I have far better brakes in my soarer now I have the supra 4 pots. Same OEM rotors (obviously different size), same brand new Intima SR6300 brake pads, same brake master cylinder brace, same car, same track, same driver, same clothes. Different day, but gimme a break (no pun intended) almost all the variables are the same.

The difference between the initial bite, braking force, stopping distance, and heat handling is absolutely immense.

Nathan Richardson
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Thursday, November 04, 2010 - 11:47 pm, by: Nathan Richardson (Richtheblack)

Ben Lipman wrote on Thursday, November 04, 2010 - 11:36 pm:
I don't give a damn about the maths. I have far better brakes in my soarer now I have the supra 4 pots. Same OEM rotors (obviously different size), same brand new Intima SR6300 brake pads, same brake master cylinder brace, same car, same track, same driver, same clothes. Different day, but gimme a break (no pun intended) almost all the variables are the same.

The difference between the initial bite, braking force, stopping distance, and heat handling is absolutely immense.

Hey Champ,

I have been thinking of your braking experiences since the start of me getting tangled up in this thread!

If you didn't make a post here, I was almost going to make you, hahaha!!!

I'm almost to the point that I will hit the brake dyno with the 4 pots and do the same with the UZZ32 2 pots (all 4 corners overhauled and discs machined with only 50kn of use) and see the numbers!!!

I still will if I have to, to prove it to myself!!!

Ben Lipman
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Thursday, November 04, 2010 - 11:56 pm, by: Ben Lipman (Ben12a)

From the stoptech site Damian linked

"Only increasing the effective radius of the disc, the caliper piston area, the line pressure, or the coefficient of friction can increase brake torque. Increasing the pad area will decrease pad wear and improve the fade characteristics of the pads but it will not increase the brake torque."

Supra brakes versus V8 or TT brakes:
increase effective radius of the disc- check.
increase the caliper piston area- check.
Line pressure- same master cylinder so no change (but I can attest to a longer stroke as the pads wear down)
Coefficient of friction- no change (in my case)

Seems like an upgrade in braking force to me.

Nathan Richardson
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Friday, November 05, 2010 - 12:00 am, by: Nathan Richardson (Richtheblack)

Ben Lipman wrote on Thursday, November 04, 2010 - 11:56 pm:
From the stoptech site Damian linked

"Only increasing the effective radius of the disc, the caliper piston area, the line pressure, or the coefficient of friction can increase brake torque. Increasing the pad area will decrease pad wear and improve the fade characteristics of the pads but it will not increase the brake torque."

Supra brakes versus V8 or TT brakes:
increase effective radius of the disc- check.
increase the caliper piston area- check.
Line pressure- same master cylinder so no change (but I can attest to a longer stroke as the pads wear down)
Coefficient of friction- no change (in my case)

Seems like an upgrade in braking force to me.

Yes, agreed!

Ben Lipman
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Friday, November 05, 2010 - 12:02 am, by: Ben Lipman (Ben12a)

Nathan- I'm actually pretty busy at the moment. I have been scanning the forums every night via the new posts button, but haven't had the time or inclination to post. I'm waiting at the moment and TV Sucks!

Clayton Carlyle
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Friday, November 05, 2010 - 12:07 am, by: Clayton Carlyle (Clayton)

Well put Ben. If this made sense, I might as well put Toyota Yaris brakes on.
Damian, take a ride in someone's car with supra brakes if you can.
Most Sports cars come out with 4 pots.

Nathan Richardson
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Friday, November 05, 2010 - 12:12 am, by: Nathan Richardson (Richtheblack)

Ben Lipman wrote on Friday, November 05, 2010 - 12:02 am:
Nathan- I'm actually pretty busy at the moment. I have been scanning the forums every night via the new posts button, but haven't had the time or inclination to post. I'm waiting at the moment and TV Sucks

Fair enough

Have you fitted the new bushes yet?? I have been holding off on mine as I have waiting for the suspension oil, valve body kit and some other bits and pieces but got the call today from Toyota that it's all here!!! Hopefully the car will be off the stands soon!

Ben Lipman
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Friday, November 05, 2010 - 12:23 am, by: Ben Lipman (Ben12a)

No bushes installed yet- I doubt I'll get to it this year.

Clayton, don't disregard Damian, he has been around these cars a long time and I reckon he has been in a car with upgraded brakes or two

. I understand where he is coming from but believe there must be a problem with the numbers as they do not support my own real world experiences.

There is a lot to be said regarding comparing your 17 year old parts taken off the car against brand new components. I added my bit because I have done close to back to back testing( I wish I had of been able to go back to Wakefield after fitting the supra brakes as well as Oran Park). I have often wondered if in some cases buying OEM isn't such a bad idea. After all the component you are replacing lasted 17 years...

Peter Nitschke
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Friday, November 05, 2010 - 06:06 am, by: Peter Nitschke (Pen)

I am not suggesting to not upgrade your brakes, just that other factors can affect your view of the effectiveness of the upgrade.

When I switched my UZZ30 front brakes for TT brakes, I also switched to Ferodo pads and decent brake fluid. It was a huge change, but I can guarantee that most was because of the pads.

Matthew Sharpe
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Friday, November 05, 2010 - 06:42 am, by: Matthew Sharpe (Madmatt)

God I am sick of these brake arguments. Bigger brakes = more friction = better stopping from high speeds and less fade. Simple really.

As stated before in other threads, they are probably the last thing you should do after ensuring you have the best tyres, good shocks, good pads etc, but if you are upping your cars power by anything meaningful with the intention of going fast, then upgrading the brakes is a must.

Matthew Crawford
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Friday, November 05, 2010 - 03:13 pm, by: Matthew Crawford (Doink)

Are you out of your mind Damien??

ok, my real world testing vs your attempts at post justification

350KW Supra, slowing from 250kph to 140kph, with the original RZ-S 2/1 pots and QFM pads, I would brake at a certain point, with 4/2 pots and the same pads I brake at a certain (later point) to achieve the same corner entry speed.

there is your real world proof.

the 2/1 pots are good brakes, they are not great brakes.

Damian Ware
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Monday, November 08, 2010 - 01:22 pm, by: Damian Ware (Frozenpod)

For those who couldn't be bothered looking at the other threads.

I have used 4 pots on my own car and driven other soarers with alternative brake systems including supra 4 pots and supra 4 pots and 2 pots yes in real life! What most people have also done when fitting 4 pots is replace fluid, use upgraded pads, new rotors which results in an improvement compared with low friction pads, poor condition fluid glazed rotors.

What most have put forward in terms of there upgrade and experiences (I am not doubting there experiences) are not comparable systems. Only (public presented) comparable systems that I am aware of were Ben and myself which we have done comparable back to back tests (Matt may have but more information is required, did you have the same tyres & suspension please list all the details of your braking system before and after). Ben and my systems are different I only used LS400 4 pots, Ben used supra big brakes all round. The results differ slightly as well but Ben used brand new components, I used second hand but in as new from a 40,000km car (the last year they were made).
Please don't assume I am just using theoretical physics and have no experience, read what I have already posted before making such comments.

Nath, floating calipers apply mechanical force from both directions but only require pistons on one side. They mechanically apply the same force on each side if they didn’t there would be an imbalance and that would result in considerable issues with wear and heating and eventually disc warping. One reason floating calipers are potentially not as good as fixed callipers is due to the potential for additional mechanical compliance which can result in a loose of braking force.

Fixed calipers apply clamping force from both sides but require pistons on each side. One of the issues with fixed calipers is additional brake fluid compliance. This requires a greater volume of fluid thus a larger bore master cylinder which requires more pedal force for the same pressure or extra pedal travel with the same master cylinder reducing brake responsiveness and feel.

The area/diameter of the pistons in the link has an error, there was a revision/correction presented with the original source but I cant find the original with the correction. Even though there is an error the formula used is correct just a typo stuff up in math. As you said the equation listed doesn’t add up to the result.

From the stopcheck white paper.
"The Caliper, Part I
It is the first functional responsibility of the caliper to translate the hydraulic fluid
pressure from the pipes and hoses into a linear mechanical force. Once again assuming
incompressible liquids and infinitely rigid hydraulic vessels, the one-sided linear
mechanical force generated by the caliper will be equal to:
Fcal = P × Acal
• where Fcal = the one-sided linear mechanical force generated by the caliper
• where Acal = the effective area of the caliper hydraulic piston(s) found on one half
of the caliper body
Note that this relationship assumes 100% hydraulic efficiency of all components in the
caliper assembly. In practical application, fluid properties, seal friction, and compliance
the physical components prevents this condition.
The Caliper, Part II
It is the second functional responsibility of the caliper to react the one-sided linear
mechanical force in such a way that a clamping force is generated between the two halves
of the caliper body. Regardless of caliper design (fixed body or floating body), the
clamping force will be equal to, in theory, twice the linear mechanical force as follows:
Fclamp= 2 × Fcal
• where Fclamp = the clamp force generated by the caliper
Note that this relationship assumes 100% mechanical efficiency of all components in the
caliper assembly. In practical application, mechanical deflection and, in the case of
floating caliper bodies, the friction in the caliper slider assembly components prevents
this condition."

As per the above statement the theory works by assuming there is enough fluid ie large enough master cylinder bore to overcome the fluid compliance and that there is minimal to no mechanical compliance. How much mechanical compliance is there in the 2 pot floating callipers (I’m sure it is slightly more than fixed callipers) very low, one way to check this is to inspect pad wear under extreme braking. IE track work, I have found that the floating callipers provide very even wear on the pads which indicates minimal mechanical compliance. On the pulsar, fitted with in comparision small and weak floating callipers; I think they have a lot of mechanical compliance as the feel is no where near as good even with brand new fluid they have always felt a bit spongy and the pads wear unevenly with a 25% difference from the inside to outside pad (with hard use). This brake system also suffers from warping rotors when they get hot most likely due to the imbalance in force and heating on each side of the rotor. Given this isn’t the case with soarer stock 2 pots I have taken the approach that they good quality, well built and have minimal mechanical compliance.

So using the stock piston sizes provides the following area.

Stock 2 pots 44.4mm diameter = 2.4 sq” area per piston> total area per side 4.8
Supra 4 pots 42.8mm diameter = 2.23 sq” area per piston> total area per side 4.46

So using your 100psi as an example per caliper.

Fcal = 4.8 X 100 = 48

Fcal = 4.46 X 100 = 44.6

Total clamping force = 2 x Fcal thus
Stock 2 pots = 96
Supra 4 pots = 89.2

So which calliper has a larger piston area and higher clamping force stock 2 pots! Btw the LS400 4 pots have the same size pistons as supras. A good way to compare systems is % difference under the same conditions such as % difference in clamping force, % difference in rotor torque. If everything else is equal combining the two will result in an overall % difference between two comparable systems

Larger rotors equals larger braking torque the exact dimensions and work out the effective radius. I don’t have time now but LS400 rotors provide roughly 3% more torque and supras another 3%.

Something for people to think about there is an age old saying 'nothing beats fresh rotors' according to QFM; rotors can and do effect friction.
Different material quality (hardness) which results in a different level of friction between the pad and rotor which also effects wear rate with the same pads and application.
Over time ie heat cycles the rotors increasing in hardness and reducing friction between the rotor and the pad (this is a small change but can be noticed and measured with brake dynos). The example I was given was the OEM AU falcon rotors were very soft, they don’t last long roughly 20,000-40,000km.

Are they poor quality cheap rotor? Nope they were designed this way to increase friction and braking force to meet standards.

Euro rotors are often also soft and offering higher friction levels compared with Japanese rotors when new.

Even though the rotor condition will have a small change in brake system performance roughly 5% this is a small change compared with the difference of fitting higher friction pads which can offer 50% more friction than OEM, but it can be the difference between one braking system being better than another and is shouldn’t be forgotten.

Calipers condition also play a role according to what I have read on car forums with hardcore track goers, targa rally competitors and those who compete in wheel to wheel racing. The much loved Brembo callipers (GTR and EVO callipers often used as upgrades) are good for about 6-7 sessions before they start to degrade and the caliper suffers increased flex reducing braking force. Motorsport calipers alcons supposedly use a higher quality materials and also cost considerably more ie 5 times the price.

Most of us we need wouldn't imagine replacing calipers with identical units would have any effect on our braking systems at most if they were seized or leaking we would rebuild them. But it can and does effect braking performance.

Also guys remember the brakes don’t stop the car, the tyres do so having the best brakes in the world and poor tyres and suspension will still not result in a car that stops efficiently.

What I take away from all this theory and my experiences is by far the biggest difference in braking performance is the pads and fluid. The stock 2 pots are very good, and unless you are running out of thermal mass a good set of street pads ie TRW Lucas, QFM A1RMs will allow you to reach the limit of even the best street tyres (meaning even with 8 pots and 355mm rotors you wont be able to stop quicker). Similarly a good set of high friction race pads ie DS3000’s, Bluestuff will also reach the limit of semi slicks with the stock 2 pots.

The down side to fitting bigger brakes 4 pots is considerably extra rim clearance required, extra pedal travel, less responsiveness, more pedal effort required, can effect brake bias (if you are only fit 4 pots up front), extra rotating mass which reduces acceleration and ofcourse the cost. From my experience the extra pedal travel and drop in response is noticeable, not dangerous but I would rather have the stock feel and response particularly for a street car driven in traffic where unexpected situations arise. For a track car this isn’t important as you plan your brake applications.

If you need more thermal mass you don’t have a choice but to fit larger rotors and calipers to suit but otherwise IMO the down sides in particularly rim clearance and cost with big brakes out way the advantages for most people ie stick with the stock brakes fit good pads and make sure you have good fluid.

For the critics I wrote the above in a hurry and I don't have time to read through it so there could be gramma and spelling errors.

Matthew Crawford
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Wednesday, November 10, 2010 - 12:16 pm, by: Matthew Crawford (Doink)

TL : DR

Anyway...

stock 2:1 Brake at a certain distance marker from speed of around 250kph to 140kph at turn 6 at Sandown

With Stock 4:2 and Same fluid (changed before every track day), same master cylinder, same tyres, same wheels, same suspension, same weather, same driver, same helmet, same shoes, same make and model of pads, same stock rotor for respective caliper, same haircut, same undies too knowing me.

I can brake noticably later,

Same with Turn 1 with is a slower corner after a slightly shorter (but still V long) straight.

I think i'll take my proven track experience over the above explanation any day.

Nathan Richardson
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Friday, November 12, 2010 - 12:28 am, by: Nathan Richardson (Richtheblack)

I generally have no problem with any of the concepts, ideas, experiences etc, but I can not for the life of me understand how a floating caliper can apply double the "gross" braking force applied by the pistons on one side?

For example, 2 pistons apply 1000lbs/sq" on one side. By design, the floating part of the caliper moves towards the rotor until there is overall equilibrium between the caliper halves and the force applied to both rotor faces.

So with perfect efficiency, shouldn't "gross force = net force"? i.e. 1000lbs/sq" is applied (gross) and would be divided equally between the two halves giving 1000lbs/sq" (net).

As I have said before, the floating caliper concept as explained in this thread (and it's links) suggests you get something for nothing! I can not see where the mechanical advantage is obtained in this setup. And even if there was, you would have to suffer a loss elsewhere.

Here is an analogy:

I have a hydraulic press. It is the conventional type where there is say, a 30 tonne ram (piston) on top (which presses down) and a fixed platform below.

I think we would all agree that the pressing capability of this, would be 30 tonne.

If I was to make some modifications to this press which made the body of the ram (piston) fixed to the platform on the bottom so they moved in conjunction with each other, i.e. floating caliper design, would I have now made the pressing capability of this 60 tonne? I do not think so, or have I? If I have, why are not all presses made like this? It would enable the same press to be basically half the size!

As the ram pressed down on the object being pressed, half the force being applied would be transferred back up through the body of the ram (piston), this force would be also applied to the platform as they are connected. The overall result would still be 30 tonne.

I have the feeling that the links posted only consider one side of the caliper to simplify the explanation or maybe not, but I can't grasp the concept that this design being able to make something from nothing.

Damian Ware
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Friday, November 12, 2010 - 08:07 am, by: Damian Ware (Frozenpod)

I have read quite a bit on this and whilst I understand the principle explaining it so that others will understand it isn't as easy. There is info on kit car forums and automotive engineering text books as well as the web.

As to the press ideal it would probably just be easier to use a larger piston in the first place as the items being pressed need to be inserted and removed regularly which would not be as easy using the floating design.

From the net

"The floating design was designed by the car manufacturers essentially to make the caliper less expensive to produce. It successfully applies the physics principle of "for every action caused an opposite and equal reaction happens." With this in mind they eliminated the piston(s) on one side of the caliper. This floating caliper is not solidly mounted, but slides back and forth on bushings or pins. When braking force is applied, the piston push the brake pad on the primary side and the reaction is the rotor being squeezed from the force of the pad primary side allowing the horseshoe shaped caliper to slide on the bushings so the secondary pads is used to squeeze the rotor. The caliper has to be very rigid retain low deflection or the principle will be lost."

Matthew Crawford
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Friday, November 12, 2010 - 02:55 pm, by: Matthew Crawford (Doink)

Lots of reading and surfing the net going on here.

not a lot of actual experience with the two.

Also, Toyota spent millions on R&D for the braking systems on the Supra, They offered an upgraded 4/2 pot braking system - not for looks, but for performance advantage over the 2/1 pot.

Damian Ware
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Friday, November 12, 2010 - 03:08 pm, by: Damian Ware (Frozenpod)

Matthew Crawford wrote on Friday, November 12, 2010 - 02:55 pm:
Also, Toyota spent millions on R&D for the braking systems on the Supra, They offered an upgraded 4/2 pot braking system - not for looks, but for performance advantage over the 2/1 pot.

They also included a 0.9G sensor which limits/starts to limit braking force to/at 0.9G which was approximately the limit of street tyres in 1995. Street tyres of today offer higher braking G forces than what they did in 1995 often around 1.2G.

Given with the stock 2/1 pots it is possible to exceed the limitation of the best modern street tyres which are offering greater rate of decelleration...

Guy Moore
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Saturday, November 13, 2010 - 10:09 am, by: Guy Moore (Thesoarerguy)

how many of you big brake boys are running slotted rotor's ?

what is your combination of tyres, pads and rotor ?

Nathan Richardson
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Saturday, November 13, 2010 - 10:53 am, by: Nathan Richardson (Richtheblack)

I have gone OEM 2/1 to OEM 4/2.

Matt Petersen
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Saturday, November 13, 2010 - 02:27 pm, by: Matt Petersen (Mattmannz)

I am running TRD slotted rotors, TRD black pads, Goodridge braided lines and Dunlop Direza's.

Ben Lipman
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Sunday, November 14, 2010 - 07:59 am, by: Ben Lipman (Ben12a)

OEM new rotors and calipers
Intima SR 6300 pads (cheap and comparable to the expensive street/track stuff)
OEM Supra 17" rims
tired old Toyo R888 street legal semi slick tyres.
Custom master cylinder brace
OEM TT brake lines (I really need to change these)
OEM TT ABS master cylinder (want to change to Non ABS SUpra- if I ever determine it is larger than the TT- and ditch the ABS as well)

Damian Ware
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Monday, November 15, 2010 - 07:57 am, by: Damian Ware (Frozenpod)

Ben Lipman wrote on Sunday, November 14, 2010 - 07:59 am:
OEM TT ABS master cylinder (want to change to Non ABS SUpra- if I ever determine it is larger than the TT- and ditch the ABS as well)

Stock non TRC soarer master cylinder has a 25.4mm or 1" bore. Supra master cylinder is available in two sizes, the same as soarer non TRC master cylinder 25.4mm and 26.9mm or 1" 1/16' to suit the big brake setup. (I cannot confirm if the booster is different but it looks to be slightly larger)

Soarer TRC brake unit master cylinder is 28.5mm or 1"1/8'.

Guy Moore
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Monday, November 15, 2010 - 08:31 am, by: Guy Moore (Thesoarerguy)

Nathan Richardson wrote on Saturday, November 13, 2010 - 10:53 am:
I have gone OEM 2/1 to OEM 4/2.

Do you take that setup on the track ?

Matt Petersen wrote on Saturday, November 13, 2010 - 02:27 pm:
I am running TRD slotted rotors, TRD black pads, Goodridge braided lines and Dunlop Direza's.

That's a good setup. What the trd pads like ?

Ben Lipman wrote on Sunday, November 14, 2010 - 07:59 am:
OEM new rotors and calipers
Intima SR 6300 pads (cheap and comparable to the expensive street/track stuff)
OEM Supra 17" rims
tired old Toyo R888 street legal semi slick tyres.

What's the brake squeal like on that at low temperature ? Do you get a lot of brake fade and shutter under heavy braking ? That's an aggressive pad for a standard rotor has it started chewing it out yet ?

Ben Lipman
Goo Roo
NT
Soarer TT manual, plus TT track car

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Monday, November 15, 2010 - 11:08 am, by: Ben Lipman (Ben12a)

Damian- from those measurements, I would probably be better off retaining the ABS master I have, and just re-plumbing it to delete traction control. What do you reckon? Don't see the point going to a smaller master with the supra item. (this possibly explains why I don't notice the change in pedal feel as much as some others -who might have had the 1" master to start with)

Guy- I have all the anti squeal gear (brand new) fitted to the calipers. I usually have a helmet on, but I have not noticed any squealing at all. Maybe Nathan might know more as he has been outside the car at some events this year.

I just went out and looked at the rotors- they look good, but I mainly do supersprints now with the longest occasional practice session being about 10 laps, not the 15 lap smash sessions I was running down south. Some wear, but no sign of a shoulder forming yet. It is worth noting that these pads have been in all year too- last year the TT gear only lasted 2 track days (working harder?)

I notice no brake shuddering at all. There is a little fade but up here we have a mammoth straight to cool them down so you don't notice it into turn one. Come the hair pin, and you do realise they have dropped off a bit after three very hard stops in a row. In the Rx-7 with the slotted rotors and bendix pads I was very nearly to the floor (panicking!) into the hair pin, and after about 5 laps the fluid was boiling. That car weighed 350kg less too.

Matt Petersen
DieHard
NA
V8

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Monday, November 15, 2010 - 11:54 am, by: Matt Petersen (Mattmannz)

Guy Moore wrote on Monday, November 15, 2010 - 08:31 am:

I was originally running standard lines, OEM pads and rotors and then upgraded to new lines, new rotors and new pads so hard to say what caused the improvements.

The pads are good, have reasonable cold capabilities and are great when warm. Haven't done any track days yet so can't comment on hardcore use.

matt.

Damian Ware
Goo Roo
Victoria
UZZ32

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Monday, November 15, 2010 - 12:19 pm, by: Damian Ware (Frozenpod)

Ben Lipman wrote on Monday, November 15, 2010 - 11:08 am:
Damian- from those measurements, I would probably be better off retaining the ABS master I have, and just re-plumbing it to delete traction control. What do you reckon? Don't see the point going to a smaller master with the supra item. (this possibly explains why I don't notice the change in pedal feel as much as some others -who might have had the 1" master to start with)

I have the same brake unit on my uzz32. I have pulled 3 down and I have to admit I don't completely understand there operation in detail.

The basic design is as follows, the power assist and TRC are an intergrated units which is where the pedal input is directed. I cannot see anyway the TRC could be removed from the rest of the unit without loosing the power assist.

The master cylinder is not quite a bog stock master cylinder with a few add ons and extra fluid paths for the TRC component. But I don't think this is a big deal as they could be plugged.

The ABS follows the master cylinder and appears to be also connected back through the TRC (could be just fluid return or may be related to applying the brake to a single wheel).

For your application IMO I would remove the unit and fit a regular brake unit from a supra with the larger diameter bore. I would do this for weight saving, no ABS and reliability as the TRC/ABS brake units are having a nasty habbit of failing.

Have you run into running out of vaccum or lack of booster power assist with your previous track work?

As this is a potential problem with hard track work (depending on how you drive)I have heard of people fitting electric vac pumps or removing the booster and not having power assist.

Allan Langford
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Vic
UZZ31

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Monday, November 15, 2010 - 01:57 pm, by: Allan Langford (Allan)

ben: why not just turn trac off? can you out brake the ABS?

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