A lot of pedal play after rear Supra TT brake upgrade
#1
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We just installed the rear rotors/brakes and now Im getting a lot of pedal play. It almost feels like Im applying the brakes twice when Im stepping on the brake pedal. Is this normal? I really dont like how it feels because when I brake almost to a complete stop, the brakes dont stop fast enough and it feels worst than the stock setup, not that they were bad. But when I brake during higher speeds it grabs pretty good.
We already bled the rears twice, do I have to bleed the fronts? Anything I can do to correct this long pedal play? I'll be installing the front rotors/calipers when I get my spacers, they wont clear on the current wheel setup I have right now. Will it get better when I replace the fronts?
We already bled the rears twice, do I have to bleed the fronts? Anything I can do to correct this long pedal play? I'll be installing the front rotors/calipers when I get my spacers, they wont clear on the current wheel setup I have right now. Will it get better when I replace the fronts?
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Only roughly 30% of your braking comes from the rear of the car. My guess is that your problem will sort itself out when you get your front ones installed. Just to be on the safe side though I would probably bleed my front brakes if I were you.
#6
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OK, so we bled the fronts today and feels a whole lot better but it still feels spongey. I'm going to try to bleed all four sides starting with the furthest on Tues to see if it helps.
The mechanic did this job for me while I was at work, he's 3 shops down. I would walk by to check on it and helped him bleed the brakes but didnt ask if the front needed to be bled.
The mechanic did this job for me while I was at work, he's 3 shops down. I would walk by to check on it and helped him bleed the brakes but didnt ask if the front needed to be bled.
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no offanse dude but what did you expect?
By only upgrading the rears you have got rid of the brake bias the stock system is intended for so of course the pressure is going to get screwed up.
If you want everything to feel oem put the fronts on and then install a supra tt mc.
By only upgrading the rears you have got rid of the brake bias the stock system is intended for so of course the pressure is going to get screwed up.
If you want everything to feel oem put the fronts on and then install a supra tt mc.
#11
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no offanse dude but what did you expect?
By only upgrading the rears you have got rid of the brake bias the stock system is intended for so of course the pressure is going to get screwed up.
If you want everything to feel oem put the fronts on and then install a supra tt mc.
By only upgrading the rears you have got rid of the brake bias the stock system is intended for so of course the pressure is going to get screwed up.
If you want everything to feel oem put the fronts on and then install a supra tt mc.
He did the TT brake setup on his 93 SC300 and his 97 SC400 without any other mods and says that the pedal response was better than his 95 TT without any pedal play.
#12
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Have you verified that the bleeder nipple is at the top of the calipers?
I swapped front/rear TT brakes, and swapping to the 98+TT master didn't do much for me when I was troubleshooting the brake pedal feel.
I also changed out the brake booster and that didn't do anything either. My pedal feel was fixed after I installed a new brake booster hose with wormgear clamps, and I installed the calipers on the correct sides of the car with bleeders up!
I swear solid air came out of the brake system for a good 3 seconds or more after I swapped the calipers.
Toyota tweaked the Supra TT brakes in 98+. They added the better abs unit, and the master cylinder bore was increased to 1.05" all for better pedal feel.
good luck
I swapped front/rear TT brakes, and swapping to the 98+TT master didn't do much for me when I was troubleshooting the brake pedal feel.
I also changed out the brake booster and that didn't do anything either. My pedal feel was fixed after I installed a new brake booster hose with wormgear clamps, and I installed the calipers on the correct sides of the car with bleeders up!
I swear solid air came out of the brake system for a good 3 seconds or more after I swapped the calipers.
Toyota tweaked the Supra TT brakes in 98+. They added the better abs unit, and the master cylinder bore was increased to 1.05" all for better pedal feel.
good luck
Last edited by RyanV; 09-10-09 at 08:47 PM.
#13
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Not yet, when we bled the brakes the mechanic had me pump the brakes while he was playing with the nipple, releasing air outta the valve. I really didnt pay any attention where the nipple was located, I'll ask him when I run into him.
This is good to hear tho, hopefully I dont have to purchase anymore parts for this upgrade. A MC or Brake booster from a MK4 will just put a bigger whole in my wallet. Thanks for the info RyanV...
This is good to hear tho, hopefully I dont have to purchase anymore parts for this upgrade. A MC or Brake booster from a MK4 will just put a bigger whole in my wallet. Thanks for the info RyanV...
#14
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Have you guys done this upgrade and swapped out the MC? I want some more opinions before I go out and purchase a MC that I might not need. I was on the Supra forums and asked a member on there that was it nessary to replace the MC, he answered NO.
He did the TT brake setup on his 93 SC300 and his 97 SC400 without any other mods and says that the pedal response was better than his 95 TT without any pedal play.
He did the TT brake setup on his 93 SC300 and his 97 SC400 without any other mods and says that the pedal response was better than his 95 TT without any pedal play.
I am the type to explore the physics of an upgrade before doing it vs. internet subjective review motivation. That is why I asked the simple question. Line pressure is a permanent parameter of clamping force and always will be in every single hydraulic braking system ever built by mankind. Science is solid. Ricing from the hip is not.
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Clamping force is delivered at the wheel through a properly bled system.
Good luck with resolving your issues. If anyone happens to get the line pressure at lock delta information between MCs, kindly post the data.
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The Mazda guys get it