850 T5 Vacuum hoses.

[Jod T5]

Originally Posted by Georgey dee

I would expect that because all the small bore pipes are for reference only and not for flow the bore shouldn't matter too much and as for length, again it's only for reference and as sometimes the pipe pressure/vacumme is already 'there' and it's only small changes is pressure that the system requires for working out what your turbo/inlet system is doing.

this is a very interesting subject georgey and im glad you have considered it too....i appreciate that there is not a great deal of volume difference between 4 and 5mm hoses but there is some...especially when you consider length....
i am still not convinced that the pressure or vacuum would still be the same at the end of a 4mm pipe as it would a 5mm pipe...for instance with a 4mm pipe i would expect the reading at the bcs to be higher than with a 5mm pipe...thus allowing the bcs to releave the pressure a fraction early, thus dropping boost...
by means of experiment i have purchased some 6mm fuel line which i am going to attach with the assistance of some mean clamping system (yet to be devised) from the compressor to the bcs....in the hope of fooling the bcs that the pressure is not as high as it may be......
any comments.....
cheers
jod

[Pedro Fandango]

i know its not the same car but it must work the same, my bro used to have a bleed valve mounted under the bonnet of his Nissan 200SX which worked very well (he could almost beat me lol). He got bored 1 day & extended all the pipework thru the bulkhead & mounted the valve on his dash so he could adjust it while driving, the extra lag/delay was that bad he ripped it all out the next day & out it back to the original set-up

i've always kept the pipes as short as poss just to keep everything nice & tidy

[Jod T5]

Originally Posted by Pedro Fandango

i know its not the same car but it must work the same, my bro used to have a bleed valve mounted under the bonnet of his Nissan 200SX which worked very well (he could almost beat me lol). He got bored 1 day & extended all the pipework thru the bulkhead & mounted the valve on his dash so he could adjust it while driving, the extra lag/delay was that bad he ripped it all out the next day & out it back to the original set-up

i've always kept the pipes as short as poss just to keep everything nice & tidy

i agree with short pipes..
whats your opinion on the diameter issue duane....in particular to the compressor/bcs pipe...i mean bigger pipe=longer delay on bcs bleeding=more boost..or is my physics wrong...
cheers
jod

[Engineer]

Hi jod, nice to see you again shame you had to fly, anyway mate the length and bore size will affect pressure and vacuum as will the expandability and collapsibility of the rubber pipe and of course temperature, hence solid pipe work is best but seldom used as flexibility is normally required.

All these variables will affect pressure / vacuum at entry and exit. Assuming some Volvo engineer has done his homework it would be prudent to maintain the status quo and calculate your mods accordingly IMHO.

Cheers

Engineer.

[Pedro Fandango]

Originally Posted by jod t5

i agree with short pipes..
whats your opinion on the diameter issue duane....in particular to the compressor/bcs pipe...i mean bigger pipe=longer delay on bcs bleeding=more boost..or is my physics wrong...

i failed science mate but what you say does make sense, i never thought of the diameter affecting the readin & just went for the size that fits (you could just ditch the BCS & go MBC lol)

[Jod T5]

Originally Posted by Engineer

Hi jod, nice to see you again shame you had to fly, anyway mate the length and bore size will affect pressure and vacuum as will the expandability and collapsibility of the rubber pipe and of course temperature, hence solid pipe work is best but seldom used as flexibility is normally required.

All these variables will affect pressure / vacuum at entry and exit. Assuming some Volvo engineer has done his homework it would be prudent to maintain the status quo and calculate your mods accordingly IMHO.

Cheers

Engineer.

hi gary, yeah sorry i did not get time to have a drive out with you...ed lost 4-0 btw...lol...
sure i agree that volvo techs have done there stuff but like you i am always searching to get every ounce of power out of my car...
my thoughts are that there is some discrepancy with regard to the diameter of the pipework that should be used...im inclined to side with duane, because i have a great deal of respect for him as a modder and im sure he is suggesting a 5mm pipe is used around the bcs..this has made me consider increasing this to 6mm to delay bcs activation...as a very cheap mod i am giving this very serious consideration...working in conjunction with the rica i would expect this to give me a boost increase accross the range....im not so sure it would be a recomendation for a mbc set up....
always nice to hear from you
all the best
jod

[Jod T5]

Originally Posted by Pedro Fandango

(you could just ditch the BCS & go MBC lol)

lol...i dont think i could trust myself.......
i still have a bleed valve to fit to the wastegate pipe but im too chicken to fit it lol........saying that it will prob play havock with the rica and retard everywhere....
cheers
jod

[Pedro Fandango]

Originally Posted by jod t5

my thoughts are that there is some discrepancy with regard to the diameter of the pipework that should be used...im inclined to side with duane, because i have a great deal of respect for him as a modder and im sure he is suggesting a 5mm pipe is used around the bcs..this has made me consider increasing this to 6mm to delay bcs activation...as a very cheap mod i am giving this very serious consideration...working in conjunction with the rica i would expect this to give me a boost increase accross the range....im not so sure it would be a recomendation for a mbc set up....
always nice to hear from you

the BCS itself won't be affected, the opening & closing of the BCS is done by the ecu, it will change the amount of air that goes thru tho within that same opening/closing time & change the boost that way

Originally Posted by jod t5

lol...i dont think i could trust myself.......
i still have a bleed valve to fit to the wastegate pipe but im too chicken to fit it lol........saying that it will prob play havock with the rica and retard everywhere....

DO IT DO IT DO IT lol, if your sensible (which you are) i don't think the rica will be too bothered by the bleed valve & adding a couple more psi. My concern would be going way too high with the boost because the remap will have raised/removed the max air limit thru the maf

[Jod T5]

Originally Posted by Pedro Fandango

the BCS itself won't be affected, the opening & closing of the BCS is done by the ecu, it will change the amount of air that goes thru tho within that same opening/closing time & change the boost that way

assuming the bcs calculates the amount of boost from the compressor....
surley with a bigger pipe the reading at the bcs will be less therefore keeping it closed for a fraction longer?.... im thinking of the reverse of a hose pipe...when the end is squeezed the pressure is higher..and visa versa??

Originally Posted by Pedro Fandango

DO IT DO IT DO IT lol, if your sensible (which you are) i don't think the rica will be too bothered by the bleed valve & adding a couple more psi. My concern would be going way too high with the boost because the remap will have raised/removed the max air limit thru the maf

lol...
agreed the boost will be effected by the bleed valve but with a little fine tuning it should be a worthwhile experiment.....
thanks duane
cheers
jod

[Engineer]

Originally Posted by jod t5

hi gary, yeah sorry i did not get time to have a drive out with you...ed lost 4-0 btw...lol...
sure i agree that volvo techs have done there stuff but like you i am always searching to get every ounce of power out of my car...
my thoughts are that there is some discrepancy with regard to the diameter of the pipework that should be used...im inclined to side with duane, because i have a great deal of respect for him as a modder and im sure he is suggesting a 5mm pipe is used around the bcs..this has made me consider increasing this to 6mm to delay bcs activation...as a very cheap mod i am giving this very serious consideration...working in conjunction with the rica i would expect this to give me a boost increase accross the range....im not so sure it would be a recomendation for a mbc set up....
always nice to hear from you
all the best
jod

Shame about the footy result mate, builds character though and as I said,

"calculate your mods accordingly" Don't guess the pipe spec work it out lol........

always nice to hear from you to

Engineer.