wanganstyl

iTrader: (5)

there is no need to change the MC. you may have air in the system; are your pads/calipers new or secondhand?

I ran supra TT calipers on all 4 corners on my sc300, a original stock sc300 healthy brake MC works great.

I have made the nipple on bottom install mistake in earlier years, it definately does puzzle you for a while (because its an obvious mistake)

dejacky

iTrader: (2)

with the front wheel off the ground, does it spin freely or is it rubbing the ls400 brake pad?

6SOARER

iTrader: (20)

So your saying that the bleeder valve/nipple is suppose to be on top? I did my fronts yesterday and installed them with the nipples on top. The brakes feel a lot better than before, but still feels like theres air in the system. I took some pictures of the rear install and noticed the nipple is on the bottom.








Front with a 15mm Ichiba V2 spacers, these were really easy to install. Now my front is FLUSHED with my fender, well more flushed than before..








Im thinking about some spacers in the rear, I really like how the car sits with the rim sitting out more..

RyanV

iTrader: (9)

There's your problem. You need to swap those rear calipers asap!

It only takes about 30min to jack up the rear and swap them..watch when you bleed the rears your going to get solid air for a bit until all that air is sucked out..remember to bleed all 4 again.

5sp_jzz30

iTrader: (2)

get the mk4 supra TT master cylinder. the stock master cylinder is not going to provide the same brake bias and pressure as intended.

on the street just about any brake can feel "solid"

hell you can have front brakes only and still drive ok

RyanV

iTrader: (9)

The original posters rear brakes are not working. That's why the pedal is soft and he is pushing through pedal pressure because of trapped air in the rear calipers.

I verified that this is the case by driving my car up onto a sliding wheel lift when I had this issue. The front wheels slid on the sliders while the rear brake that were supposed to stop the car did not work!

I actually missed TX2K9 because of this

RyanV

iTrader: (9)

See that brake bleeder valve there at the bottom of the caliper? That should be up top, and the caliper is on the wrong side of the car.

wanganstyl

iTrader: (5)

yups. thats called installation FAIL; happens reasonably often actually, for some reason calipers can be swapped and mounted upside down, people overlook it and try to drive.......it dosnt work very well.

I ran my car as DD in san francisco and on trackday open tracking (infineon) with 4 corners supra TT brakes + stock sc300 master cylinder and brake booster. lots of wangan runs, trips to LA as well......

if you know how to modulate your brakes, you do not need to change the master cylinder. if you want to waste money for no reason, go for it. You may find a slight difference in pedal feel, or not. Car will stop exactally as fast/slow as before the MC change

if you have a dead MC and brake booster and have a crashed MK4 TT and want ot hybrid, go for it.

6SOARER

iTrader: (20)

I just finished flipping the rears around and man am I IMPRESSED. The stopping force on this setup is CRAZY, feels like I need a 5 point harness to hold my upper body back from shooting forward. That did the trick.

Good looking out Wangan and Ryan, ya'll really knew what ya'll were talking about . To those of you that insist that I needed a MC or a brake booster, no offense but ya'll dont know diddly BIG TIME FAIL!!!!

dejacky

iTrader: (2)

try spinning each of the wheels freely when the car is lifted up and in neutral. Does the wheel still rub the brake pad when the brakes are not engaged?

Rex Ruthor

From someone who installs calipers upside down? Classic.

Care to quantify your seat of the pants brake torque at wheel increase via physics? Measure your caliper piston and rotor diameters stock vs. Supra and I'll be glad to do the math for you with MC line pressure at lock being the static control constant.

Remember, your car is as fast as it feels. No need to measure it.

6SOARER

iTrader: (20)

No they dont. Matter of fact I need to replace the brake pads probably in the next 2k miles or so.



I rather do the install backwards and find out later that it was wrong than buying parts that wasnt nessacary. Besides I didnt do the initial install, I payed a guy to do it. I was too lazy to do it myself and wanted them on at the time. I kinda rushed the rears and dude EFFED up.

Anyhow, my TT brake setup works with great results

Rex Ruthor

Glad it worked out. For the record, I never told you to change MCs. I will still do the math for you if you want to quantify your gains. The important thing to remember is that the stroke volume of brake pedal depression must be larger to move bigger caliper pistons which means more pedal travel. The Laws of Physics still apply. If that increased pedal travel is acceptable in the real world, then more power to everyone who does it. However, it may be nice for the modders out there to claim an actual variable in brake torque increase and even better if it gain sum out to shorter stopping distances. That can only be done by equating clamping force and then equating brake torque at wheel. Then, measuring stopping distances before and after modification. Other things to pay attention to would be keeping modded calipers in line with original brake bias (front to rear). Also, to insure that if the cumulative piston mass increase on the modded system using the stock MC can produce enough clamping force to operate within the parameters of the ABS computer protocols. I suppose one could always rip out their ABS system to enhance braking as well, though.

lengnoou

iTrader: (1)

sounds like a physics class in here. i think that if the modder feels comfortable with their set up and the way it feels then leave it at that. unless people are the engineers of the whole abs brake set up unit or tt brake crap, their "factual" arguments are jibberish to me. no offense. experience and common sense will always prevail over knowledge learned through a book. but back to the original post, doesn't the calipers have an "R" and "L" stamped onto it on the inside of the caliper? i would assume that those designate "right" and "left" calipers correct? im about to install my fronts once my left caliper comes in and on my right caliper theres an "R" stamped on it. reading this thread was interesting and humerous at the same time.

6SOARER

iTrader: (20)

Yeah, I didnt understand half what he was saying and wasnt interstered in his MATH so I left it at that.

I really didnt inspect the calipers when they were off. I'll check today when I pull the rears off to replace the pads with new ceramic pads. I know that the rotors have "R" "L" stamped on them, I would think it wouldnt matter unless there cross drilled rotors but there stamped for a reason I guess.