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blow off noise without blow off valve ?

Messages
3
Likes
1
Location
Dundee
#1
Hi All!

Just bought my first fiesta a couple a days ago, all Stock except montune box+hose, so just noticed when im revving a bit (2500-3000rpm) hearing some blow off noise , also when im accelerate and let it off hear some chirp and blow off :) previous owner says there is no blow off valve fitted , so my question is can the montune box cause this kinda sound ? or anyting :D

Thank You
 


the duke

Senior Member
Messages
935
Likes
886
Location
Cleveland
#2
Your car has an OEM bypass valve. It will make noises as it vents the excess pressurized air (Boost). It vents back into the OEM intake tract so it's not as loud as venting into the atmosphere. Pretty much any forced indcution system needs a bypass valve/pop-off valve/blow-off valve to function correctly.

Your Mountune Airbox has a secondary hole/airfeed and will be more audible for it.
 


Messages
18
Likes
13
Location
texas
#3
Hi All!

Just bought my first fiesta a couple a days ago, all Stock except montune box+hose, so just noticed when im revving a bit (2500-3000rpm) hearing some blow off noise , also when im accelerate and let it off hear some chirp and blow off :) previous owner says there is no blow off valve fitted , so my question is can the montune box cause this kinda sound ? or anyting :D

Thank You
have the same setup. mountune air box w/ hose and a drop in filter. get crazy bov noises.
 


OP
K
Messages
3
Likes
1
Location
Dundee
Thread Starter #4
Your car has an OEM bypass valve. It will make noises as it vents the excess pressurized air (Boost). It vents back into the OEM intake tract so it's not as loud as venting into the atmosphere. Pretty much any forced indcution system needs a bypass valve/pop-off valve/blow-off valve to function correctly.

Your Mountune Airbox has a secondary hole/airfeed and will be more audible for it.

Thank you !
 


Messages
7
Likes
0
Location
Hemet, CA, USA
#6
My car all of a sudden started to blow off all loud and turns out all 3 bolts of the turbo inlet pipe were gone...fell off
 




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