For the love of God... tell me how pressure works!!!

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MMamdouh
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For the love of God... tell me how pressure works!!!

Post by MMamdouh »

hi guys

you know i have done a brake upgrade on my 1.5 SOHC lanos and i have now 1.6 spec braking system.

http://www.daewootech.com/forum/viewtopic.php?t=9527

since then i was suffering from premature wheel lockup at my left wheel... if you go back to the main upgrade topic you will find that this wheel has a longer brake hose than the other wheel.

http://www.daewootech.com/forum/viewtopic.php?t=9626

i got fed up with this problem so i went to the mechanic yesterday determined to solve this issue once and for all, the mechanic suggested that we revert to the OEM 1.5 SOHC lanos brake hose that is "shorter" than the nubira hose tat i am using... as far as my knowledge goes with pressure... shorter hose should make his problem even worse as the pressure loss will be even lower and the wheel should now lock even more prematurely than the before

the mechanic just grinder the sharp edges of the hose to match the circular part of the caliper as you can see:

Image


i went for a test drive expecting massive lockup at the left wheel... surprisingly the lockup issue was gone!!!!!!!!

i am glad the issue is solved but it just can't get how the hell did this happen? i know for sure that rubber hoses causes pressure "loss" and will affect brakes balance by "lowering" the pressure going to the caliper and thus makes the other wheel - with the shorter hose - lockup prematurely... i was having the issue the other way around with the longer hose and that i couldn't comprehend.

i am sure that now i don't understand the concept of pressure correctly as my current understanding contradicts with a real life situation where the shorter hose did manage to lose more pressure than a long one.

can someone kind enough help me here and ex[lain to me how did this happen and what is the logical explanation to this fact??

MMamdouh
Driving is the utmost fun you can have with your pants on!
Check out my ride: http://www.cardomain.com/ride/567267
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Daniel
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Post by Daniel »

Maybe the longer hose was stiffer (I mean thicker walls) than the stock one and deforms itself less. So the "pressure loss" was reduced hence prior blocking.

Just my 2ct.

Daniel
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PrecisionBoost
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Post by PrecisionBoost »

I'd say it was just a stroke of luck that it worked.... it would be very hard to come up with a logical explaination as there are a number of factors that could affect the pressure
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MMamdouh
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Post by MMamdouh »

called a couple of petrol heads of mine and they said logically the longer hose should cause the wheel to lock a bit later than the short hose... but their are many other factors here

they said that the longer hose could be harder and thus it doesn't flex or expand as much as the short one... also it could be the 7 years old short hose that got weakened by the 76k kms and those 7 years made it more flexible than the brand new nubira hose

also it was said that the nubira hose could have a smaller inner diameter and that will make it lose less pressure than the short one.

so as you can see their is more to it than just hose length... or inn other words i assumed that "all other factors are the same" where they were not

this brings us to an important question... will switching to nubira hoses "long and stiff hose" be considered as an upgrade? i have established that the longer hose does respond better to braking for a few months now so i if did but the same hose on both wheels then i will have balanced braking power and the brakes will be more responsive than it is with the short OEM hoses.

is this logical and worth trying? or am i talking from my ass again??

MMamdouh
Driving is the utmost fun you can have with your pants on!
Check out my ride: http://www.cardomain.com/ride/567267
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PrecisionBoost
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Post by PrecisionBoost »

As I said there are a number of factors..... which your petrol head friends pointed out..... sometimes it's just a matter of trying it out to see what works best as there is not logical way to figure it out..... experimentation is the only way to truely determine what happens when you slam on your brakes.
2010 BMW 335D
1994 Opel Calibra 4X4 turbo ( C20LET 2.0L Turbo )
2002 Daewoo lanos
MMamdouh
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Post by MMamdouh »

thanks for the advice... i will buy another nubira brake hose and swap my current hoses and see if it will enhance by brake responce

thank you guys for the help... will keep you all posted

MMamdouh
Driving is the utmost fun you can have with your pants on!
Check out my ride: http://www.cardomain.com/ride/567267
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