booster or booster less?

[Guest]

I am in the process of planning my new breaking system and I am trying to figure out if I want to keep my booster. I am going to be running the big front break kit and rear disk kit from Ireland.

I really like the look of the Alpina style pedal box and the simplicity of pressing directly on the Master. But is this ok for Street use?

I think I have seen most of them on the FAQ but photos of peoples boosterless setups would be greatly appreciated.

many many thanks.

[TobyB]

How big are your thighs?

If you can split the seams on jeans just by flexing, ditch the booster.

If you get called twiggy, keep the booster.

The deal is, you CAN make the 2002 system work well without a

booster, but unless you really work at it, you end up with high pedal pressure.

A really small master fixes that (especially if you go to rear discs) but

finding the right SAFE cylinder's not trivial.... I haven't even looked.

Whatever you do, don't permanently mod the car. Changing pedal boxes is

easy, (and a good way to experiment) but cutting up the firewall

is harder to undo if you decide it sucks.

my '02

t

[dubois]

I test drove a 2002 without a booster, and for street, race, or anything imaginable is no good, it takes way too much force to make the car stop. Easy is always good.

[chad]

I was getting ready to ask the same question. I have IE's 300mm BBK, 320 MC, and 320 rear drums. I like how the pedal feels when the car is not running but not when the booster is working. There is a lot of movement. I guess I am used to 510's. I am not going to change anything until I run a shakedown and go from there. If all else fails I will just plug the system and try that before making any other changes.

[TobyB]

Thing is, you kind of have to redesign the system to work without the booster,

as it's been designed to work with it.

If you just kill vacuum, it's brutal. And you have to travel all the way

through the booster to get brakes, as the booster uses up a bit of travel

to progressively open the valving on it.

But if you're really into it, you COULD get it to work.

One of the other things to overcome is that the pedal ratio's very low

on an '02- I seem to remember on the order of 4:1. Because of the short

pedals, mostly. This means that

you need a large hydraulic ratio to balance it, and that means a small master.

THAT means that you don't get much fluid displacement, and can run

out of travel in the master. Bah.

The fix is to increase the pedal ratio when you convert the box over

(6:1 is a lot better, and more- or- less standard)

by moving the master attachment point closer to the pivot. However, this

raises local stresses, and that means a double- shear clevis or similar.

AND you run out of room because of the physical size of the pivot.

If it sounds like a lot of work- it is. But after changing the race car over,

I really like it- for the track. On the street, I live with the booster.

Because I'm lazy and also because I don't know any lawyers. And like it like that.

fwiw, my 122 has a non- boosted system, and it works pretty well.

But the pedal ratio's a lot higher. It's also very sensitive to pad type.

Don't show me any MetalBastards, that's for sure!

because I don't want to go back to beating my head against BSS Blue,

t

[Guest]

Thanks Toby,

I think I am going to stick with the booster. It is a cheep enough modification so I might get a used pedal box and see what I can come up with.

I have seen the photos of your dual master setup, looks killer. any process shots? or more photos?