Brake MS sizing vs pressure question

[jonra23]

What is with the engineer bashing all the time.

Ever thought that maybe the answer is right but the question is wrong?

If the question included "with a pedal applied pressure of #?# at maximum tyre adhesion" the answer would have allowed for it.

The other classic is "took my car to the engineer to get it passed and he said my #?# is no good", well did you talk to him about it before you modded you car and asked him to sign a piace of paper to say it is all good.

My bitch for the week.

No I am not an engineer.

regards
jon

[kingmick]

dont lock it it! im down racing next month and cant remmeber piston sizes and masters off the top off my head at the moment! we can see how well it matches the math

jonra23 there is no engineer bashing going on at all?

[skiddz]

good maths stu, if people wrote less crap and did more maths id understand

ill explain it in simple terms for mick , the longer the stick on the brake pedal the less force you have to use to make yourself go less fast

[kingmick]

This should be a good one stew, its a basic setup and i found the data for it, dont cheat anyone as this is what young engineers cut there teeth on.
calipers X 4 there all 1.260{in} per caliper{same calipers front and rear}

pedal ratio = 2.174{in}

Now work out Master Cylinder sizes{two MS's}

then we can go the next step of working out line pressures etc!
have a feeling this will turn in a fun thread!

p,s no cheating anyone as your only cheating yourself

[jonra23]

What applied pedal pressure do you want and what clamping pressure do you want front and rear?

regards
jon

[kingmick]

good maths stu, if people wrote less crap and did more maths id understand

ill explain it in simple terms for mick , the longer the stick on the brake pedal the less force you have to use to make yourself go less fast

Yes mate thats because you dont know anything about how things work
Dont give me simple terms mate cause you know nothing at all and need it handed to you on a plater because you have no experiance at all!
What are the common pedal ratios for racing skiddz and why? hahahahahahahahahahahahaha

[kingmick]

What applied pedal pressure do you want and what clamping pressure do you want front and rear?

regards
jon

Well do you most people know those things on here choosing masters for calipers?
See you missing the point, work it out. The above brake setup gives it away to what it is but ill make it a bit easyer his a bit more.
car weight is 640 pounds and CoF is 0.670

The point is to learn as you go, this isnt a pissing contest or engineer bashing{its engineers data!hahah} its to learn.

[TA-022]

that just messed me up skiddz ??

[takai]

The point is to learn as you go, this isnt a pissing contest or engineer bashing{its engineers data!hahah} its to learn.

Not a pissing contest or bashing mick??

Yes mate thats because you dont know anything about how things work
Dont give me simple terms mate cause you know nothing at all and need it handed to you on a plater because you have no experiance at all!
What are the common pedal ratios for racing skiddz and why? hahahahahahahahahahahahaha

Seriously, this thread was, and still is making good points, no need for the utter crap

[kingmick]

i was saying im not bashing?? what did it sound like?


Please, mate have a look at skiddz post again! was answering him!

anyway back on topic!

I found the data this morning after a quick look and thought it would be an intresting exercise!

[jonra23]

At the risk of being rude it is questions like the one Mick has stated that in post #34 that lead to f@#k ups in master cylinder selection (in this example) and give me cause for post #31.

There is missing information that leads to assumptions being made, assumption right = user happy, assumption wrong = user unhappy. Doesnt mean the answer is wrong means that it was made with the wrong information.

Not trying to give you a hard time TurboRA28 or KingMick.

regards
jon

[kingmick]

You dont sound rude at all! but i was going to give all the data at the end for the whole thing with all the measurments for everything.
I just thought it would be intresting! if noone thinks its intresting ill just post the data, i just thought knowing the answers before dosnt help to work things out, i could be very wrong, but im only human

[TA-022]

bring on the data .. would be intersting to see the results from certain combinations.

[oldcorollas]

data needed (as a guess):
-pedal leverage ratio
-caliper piston size for all calipers (pressure and fluid volume)
-pad retraction/knockback distance (for fluid volume)
-freeplay in balance bar and pedal, as measured from pedal
-disc size, with inner and outer pad contact diameters (for leverage)
-pad size (length and width) (for leverage)
-maximum and minimum pad coefficient of friction (or the range you will use it in)
-tyre diameters, front and back (for leverage)
-tyre coefficient of friction
-contribution of aero to increased effective weight of car, front and rear at different speeds
-weight split on each tyre
-weight transfer to front of car during braking
-transient weight transfer before car settles into braking

now to the subjective ones:
-pedal travel required by driver (very important for fluid volume)
-pedal force at which driver wants to modulate braking pressure
-weight transfer off inner wheels when braking and cornering
- driver perceived required brake bias

this is just a basic list, but with that info, you can make a fairly good prediction however, if the data provided is incorrect, then an accurate prediction cannot be made.

anyway, the algebra above was to answer the original question of MS sizing vs pressure.

there are plenty of book of braking systems that i suggest people read

[kingmick]

ok no one wants to have a crack at seeing if they can get close,ill just post the data then!