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5-lug swap, Stage3 Clutch, AWD Conver. DONE!


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I doubt that any difference in the booster would cause any issue beyond a different feel to the pedal. Once you get in it and drive around, you will know how hard you need to press the pedal to stop; if you have to apply too much pressure, then you know you need a larger booster (you wussy, just stand on 'em!)

 

Personally, I have always wondered if one could just install a hugeass master cylinder (thinking like, 2 1/2 inches) and forego the whole power brake thing entirely.. I havent really talked about it to anyone with a BETTER knowledge than mine in the field of fluid dynamics, though.. and I only know just enough to start getting me into trouble. I am unsure if a larger bore cylinder would actually solve the problem. It might also take a cylinder with a longer stroke, and THAT may be impractical.. which would explain why auto engineers just use a vacuum booster, rather than these other ideas that I have that seem like such better solutions...

 

any thoughts on THAT? :brow:

 

Hi I'm somewhat new to the board but not to cars. If my understanding is correct bigger master cylinders equal more not less pedal effort. Fuild dynamics states that pressure per square inch is the same everywhere in a closed system so if you push 50 lbs of effort at a half a square inch of master cylinder piston vs a 1 square inch piston (numbers used for simplification) you get twice the pressure against the caliper pistons on the small master cylinder. The reason for needing a bigger master cylinder comes when you just cant push enough fluid to move the caliper pistons. If you have to go up you still want to keep the mc piston as small as you can.

 

Least wise that's what I recall. Btw that rocks. I live in West Linn and would love to see that beast in person one of these days. What does she turn at the track..??

 

Thanks

Renny

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In order to get the most from the larger XT6 brakes the larger or matching master cylinder is a MUST otherwise you dont get the clamping power that you should.

 

 

I wounder if the brake boosters are different as well?

 

I took allot of Steering and Suspension Classes in College and all of these factors play a big role in the design and operating of the brake system, the slightest change can make a huge difference with brakes.

 

 

Well, you should drive a stock brake'ed WRX on track...then drive the same one with StopTech 4 piston's in the front on a 366mm dia. rotor.

 

There's no need to upgrade the stock MC. PLENTY of stopping power with more than enough brake pedal effort left untouched.

 

I'd say that I was using 120 to 150 lbs of force to get the car slowed into the corners...with the stoptechs using the same braking points, that force was 1/2 of that. Then i started going deeper and deeper...when I was back to using 150 or so lbs of force...I was WAY deep.

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Hi I'm somewhat new to the board but not to cars. If my understanding is correct bigger master cylinders equal more not less pedal effort. Fuild dynamics states that pressure per square inch is the same everywhere in a closed system so if you push 50 lbs of effort at a half a square inch of master cylinder piston vs a 1 square inch piston (numbers used for simplification) you get twice the pressure against the caliper pistons on the small master cylinder. The reason for needing a bigger master cylinder comes when you just cant push enough fluid to move the caliper pistons. If you have to go up you still want to keep the mc piston as small as you can.

 

Least wise that's what I recall. Btw that rocks. I live in West Linn and would love to see that beast in person one of these days. What does she turn at the track..??

 

Thanks

Renny

 

*smacking*myself*in*the*forehead*

 

Yah, yah, you are right!! to make my idea work it would take a LOOONG and skinny master cylinder.... not necessarily alot of travel in the pedal, because you can alter your fulcrum point.. but at least I finally see that I am trying to engineer around something that I cant engineer around, and why.

 

Thanks, man, I am glad I bothered posting that after all...

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