how consistent is a MBC?/ my motor issue
#1
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how consistent is a MBC?/ my motor issue
might as well start from the beginning. so sunday was an auto-x event in the rain. during runs im using meth/water injection 7-23 psi. all of a sudden during one of my runs i cannot seem to rev past 4/5k rpm...it bounces back at me hard like its hitting the rev limiter. so basically i cannot get into boost. (top end power setup) this is happening consistently i noticed right at around 7 psi.
finish the event, drive home and verify yes its bouncing back at me at 6-7 psi. noticed the spray light wasnt coming on so changed it to base map (19psi/no meth) and bouncing back at me still. yes i did forget to unplug the meth actually but it still shouldnt be bouncing back at me like a rev limiter..
next day(no rain), problem was gone. im thinking the rain having to do with this issue? rain did reach into the engine bay for tech inspection, etc. also i should mention at the auto-x heater only works about 1/2 of the time (could this have to do with removing my AC fuse?), and car did not start once (but re-cranked it again and was fine after that). btw i put an ac fuse back in.
What i did notice though the MBC is off from where i marked it with permanent marker on the unit. ie base map is 19psi at the pen mark but now its boosting around 16-17 psi. the pen marked for meth map is suppose to be 23 psi but now is only boosting about 20 lbs.
1) one tuner says MBC are VERY consistent. it could be a boost leak.
2) another tuner says the spring tension can change, so you have to compensate by adjusting a different spot once in awhile for a given max boost.
this MBC is only 3-4 months old.
im pretty well sure i do not have a leak, but i will check again in the morning.
any feedback would be great on this!
btw i have the hallman rx pro MBC.
finish the event, drive home and verify yes its bouncing back at me at 6-7 psi. noticed the spray light wasnt coming on so changed it to base map (19psi/no meth) and bouncing back at me still. yes i did forget to unplug the meth actually but it still shouldnt be bouncing back at me like a rev limiter..
next day(no rain), problem was gone. im thinking the rain having to do with this issue? rain did reach into the engine bay for tech inspection, etc. also i should mention at the auto-x heater only works about 1/2 of the time (could this have to do with removing my AC fuse?), and car did not start once (but re-cranked it again and was fine after that). btw i put an ac fuse back in.
What i did notice though the MBC is off from where i marked it with permanent marker on the unit. ie base map is 19psi at the pen mark but now its boosting around 16-17 psi. the pen marked for meth map is suppose to be 23 psi but now is only boosting about 20 lbs.
1) one tuner says MBC are VERY consistent. it could be a boost leak.
2) another tuner says the spring tension can change, so you have to compensate by adjusting a different spot once in awhile for a given max boost.
this MBC is only 3-4 months old.
im pretty well sure i do not have a leak, but i will check again in the morning.
any feedback would be great on this!
btw i have the hallman rx pro MBC.
#4
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thanks for the feedback (i mean it),
but i cant see how that would affect my meth spray light not coming on and me consistently bouncing back at 7 psi. hm..
but i cant see how that would affect my meth spray light not coming on and me consistently bouncing back at 7 psi. hm..
#5
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also ive driven in the rain many times with this setup and never had such a dramatic problem as this (i have an APS CAI which sits right beside my passenger tire down low)
#6
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ya, sounds like you hit a puddle, got some water on/in the filter, i have had it happen to me plenty of times.
the meth light will not come on and you wont be able to go past a certain rpm till the water gets out of the intake/filter.
thats why i chose the short ram the second time around. it gets cooled through the intercooler anyways and i can completely block the fender off
the meth light will not come on and you wont be able to go past a certain rpm till the water gets out of the intake/filter.
thats why i chose the short ram the second time around. it gets cooled through the intercooler anyways and i can completely block the fender off
#7
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Sorry to hear bout that se0ul.
I think it may be the intake as well. I actually put my stock intake back in and sold my APS. With our APS intakes you have a chance of getting water in there which would be BAD other than that the APS is a great intake.
I think it may be the intake as well. I actually put my stock intake back in and sold my APS. With our APS intakes you have a chance of getting water in there which would be BAD other than that the APS is a great intake.
#8
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ya, sounds like you hit a puddle, got some water on/in the filter, i have had it happen to me plenty of times.
the meth light will not come on and you wont be able to go past a certain rpm till the water gets out of the intake/filter.
thats why i chose the short ram the second time around. it gets cooled through the intercooler anyways and i can completely block the fender off
the meth light will not come on and you wont be able to go past a certain rpm till the water gets out of the intake/filter.
thats why i chose the short ram the second time around. it gets cooled through the intercooler anyways and i can completely block the fender off
sucks cause my FMIC doesnt do well with a whole lot of intakes fitment wise lol... i dunno any short ram that can fit.
i have the WBR FMIC. maybe ill try the wbr intake.....
#13
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hey seoul. i have a spt short ram intake sitting in my parents garage if you want to just test fit it on your car. haven't really decided on whether or not i want to sell it, but since i have it lying around, i could help another subie owner out. i'm not sure if you're in the bay area or colorado at the moment, but just a thought.