mbc vacuum lines?

DC_T · Post by **DC_T** » Mon Dec 31, 2007 3:22 am

i am installing a turbo xs mbc, but can't remember how the vacuum lines are supposed to run. i'm a little confused on what to do w/ the nipple on the compressor housing of the turbo. do i just T it in w/ the wastegate nipple, or plug it? and where should the mbc be T'd in? any help is appreciated.

my guess is to run a line from the intake manifold to the mbc, to the side nipple on the wastegate, and just plug the compressor nipple. sound right?

mike93hatch · Post by **mike93hatch** » Mon Dec 31, 2007 4:10 am

no.

run a line from fitting on compressor to the correct fitting on the MBC and then the other line on the mbc to the side port of the wasetgate.

if you run the line from the intake manifold then your wastegate will be seeing vacuum and COULD damage the diaphram. you just want the wastegate to see boost pressure and that is all it will see if running the line from the compressor of the turbo.

DC_T · Post by **DC_T** » Mon Dec 31, 2007 5:35 am

mike93hatch;87821 wrote:no.

run a line from fitting on compressor to the correct fitting on the MBC and then the other line on the mbc to the side port of the wasetgate.

if you run the line from the intake manifold then your wastegate will be seeing vacuum and COULD damage the diaphram. you just want the wastegate to see boost pressure and that is all it will see if running the line from the compressor of the turbo.

thats basically what turbo xs has on their site. its tough to get a straight answer. seems like some guys run from the intake manifold and just plug the compressor nipple, and some guys run from the compressor.

i'm thinking what you said is how it was hooked up before. so i guess i will give that a shot.

what line would be best to T off of for a boost gauge?

mike93hatch · Post by **mike93hatch** » Mon Dec 31, 2007 6:16 am

DC_T;87848 wrote:thats basically what turbo xs has on their site. its tough to get a straight answer. seems like some guys run from the intake manifold and just plug the compressor nipple, and some guys run from the compressor.

i'm thinking what you said is how it was hooked up before. so i guess i will give that a shot.

what line would be best to T off of for a boost gauge?

you dont have any extra nipples on the intake manifold? get rid of some emissions crap so then you have a extra nipple.. or can you since you live in stl? otherwise just T off the brake booster line or the FPR..but then youre going to need a place to run the BOV line..if so just get a vacuum block and T the block off the brake booster.

DC_T · Post by **DC_T** » Mon Dec 31, 2007 4:29 pm

oh ok, i do have an extra nipple on my IM that i can use. i was thinking i'd need to tap into the mbc line to get an accurate read, but it sounds like any vacuum source would work.

thanks for your help man. hopefully i can get this thing running today!

mike93hatch · Post by **mike93hatch** » Mon Dec 31, 2007 10:19 pm

DC_T;87912 wrote:oh ok, i do have an extra nipple on my IM that i can use. i was thinking i'd need to tap into the mbc line to get an accurate read, but it sounds like any vacuum source would work.

thanks for your help man. hopefully i can get this thing running today!

no... if you tap into the mbc line that is hooked to the compressor... your boost gauge will not show any vacuum, only boost. hook it to the intake manifold.