boost???

[mike 850]

hi, got a bit of a prob, got a 95 850 t5, ive fitted a mbc and boost gauge, the prob is the boost will quickly rise to aroun .6 bar but then drop down to around .4, adjustin the mbc doesnt seem to be making any difference, could this be a boost leak? where do i start first, eg the pipes connected to the mbc? thanks in advance

[Andrew]

hi, got a bit of a prob, got a 95 850 t5, ive fitted a mbc and boost gauge, the prob is the boost will quickly rise to aroun .6 bar but then drop down to around .4, adjustin the mbc doesnt seem to be making any difference, could this be a boost leak? where do i start first, eg the pipes connected to the mbc? thanks in advance


Standard T5s should be .8 bar from memory. Do you have this problem without the MBC ?

[spesh]

.8 of a bar seems a bit high for standard boost, the t4's run that standard but im sure the T5's are more like 7 so .5.

[Andrew]

.8 of a bar seems a bit high for standard boost, the t4's run that standard but im sure the T5's are more like 7 so .5.

T5R is .8 as standard I know that much.
1.2 with 15t rica
1.3 with 19t rica

[Al115]

My V70 1999 should have been 0.7bar / 10psi as stock.

[volvotuning]

Most standard 850 T5s run around 0.5 to 0.6 bar.

Adam.

[mike 850]

before the mbc it would go up to .6 bar, when i first put the mbc on i set it on .8 and it stayed there to the redline , now it seems to drop off? it does seem to sound louder( rushing air) but not sure if thats coz of the k&n

[Lee-J-T5]

Most standard 850 T5s run around 0.5 to 0.6 bar.

My 96 T5 always boosted to 0.5 bar as standard, I fitted the gauge before the MBC. Now it goes up to 1 bar and settles at 0.9 pulling like a train

[craig]

check your hoses arent too long or too soft cos this will cause that to happen also what type did you get and are the hoses held on securely and not leaking .if you post a picture that might help

[mike 850]

just to update, i am a TOTAL tw@t :) , after changing all the vacum hoses to the mbc, i realised that where i mounted the mbc i taped some foam around to cusion it from rubbing against the intake hose :slap: :slap:
this totally blocked the pin hole on the end of the mbc, took this off and now its back to .9 bar and holds all the way :B_steerin , all i can say is im an idiot but im so pleased i found out what the prob was!! thanks for all the help

[Andrew]

Well it's all a learning experience. I'm glad you got it all sorted.