brake booster + open throttles?

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Postby sergei » Thu Jul 12, 2012 10:31 pm

touge_ae101 wrote:how does it work for a turbo car then? presumably when its on boost there is no vacuum?? what happens if you want to left foot brake etc?


It work same way on turbo as on N/A, check valve. It is even plugged in same place.
Once throttle is shut (when braking) there is vacuum (more than enough to operate brake booster).

The problem on turbo cars is when you have anti-lag you have no assist from booster. Same problem happens when you left foot brake while full throttle (on N/A and boosted).
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Postby cat007 » Thu Jul 12, 2012 11:12 pm

sergei wrote:
touge_ae101 wrote:how does it work for a turbo car then? presumably when its on boost there is no vacuum?? what happens if you want to left foot brake etc?


It work same way on turbo as on N/A, check valve. It is even plugged in same place.
Once throttle is shut (when braking) there is vacuum (more than enough to operate brake booster).

The problem on turbo cars is when you have anti-lag you have no assist from booster. Same problem happens when you left foot brake while full throttle (on N/A and boosted).


About that - in theory if you were left foot braking - you could still have a bit of brake force from the vacuum left in the brake cylinder? Until you lift off the brake and re-apply? Much like when you try and use the brakes after you've shut the engine off. You get 1 or 2 pumps and then you're done.....*cough cough*

?
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Postby sergei » Thu Jul 12, 2012 11:27 pm

cat007 wrote:
sergei wrote:
touge_ae101 wrote:how does it work for a turbo car then? presumably when its on boost there is no vacuum?? what happens if you want to left foot brake etc?


It work same way on turbo as on N/A, check valve. It is even plugged in same place.
Once throttle is shut (when braking) there is vacuum (more than enough to operate brake booster).

The problem on turbo cars is when you have anti-lag you have no assist from booster. Same problem happens when you left foot brake while full throttle (on N/A and boosted).


About that - in theory if you were left foot braking - you could still have a bit of brake force from the vacuum left in the brake cylinder? Until you lift off the brake and re-apply? Much like when you try and use the brakes after you've shut the engine off. You get 1 or 2 pumps and then you're done.....*cough cough*

?


yeah, couple of pumps all you have.
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Postby matt dunn » Fri Jul 13, 2012 10:16 pm

touge_ae101 wrote:how does it work for a turbo car then? presumably when its on boost there is no vacuum?? what happens if you want to left foot brake etc?



wordnz wrote:There's still vacuum before the turbo.



What????? if there is vacuum before the turbo you need a new air filter.
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Postby iOnic » Fri Jul 13, 2012 11:08 pm

^ I think he meant that there is vacuum before boost so the booster can store it
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Postby allencr » Sat Jul 14, 2012 7:09 am

touge_ae101 wrote:hmm been thinking about this some more and could it be possible for my left foot braking to cause this problem?


Yes, more playing with the pedal will deplete the vacuum sooner.
If your technique hasn't changed, then something else has.
I'd guess that the pads have gotten a taper(they all do, no way around it) from hard use, and the extra amount of travel they need is what's now using up your vacuum.
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