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BOV valve installed. Feels power is lacking

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35
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11
Location
Orlando
#1
I usually post on fiestast.org, but it seems things are more active here. I just installed a MiniCooper BOV valve on my stock fiesta for noise. It fits perfectly; however, when I tried to mount it on my car, the bottom bolt stripped and the BOV valve is not sitting flush with the car. There is no open because metal is covering it. All O-rings are in place, I just couldn't sit the BOV valve flush. The turbo noise is great, but it feels my turbo is not kicking in soon enough. I feel my 0-60 times feels like it slowed down a little and I feel cannot push the car as fast as normal.

I don't have actual metrics written down, but after driving the car for three years, it just doesn't feel right. I need to remove the BOV valve to run tests, but I have to take out the stripped screw first.

Anyway, has anyone experienced a drop in acceleration after installing the boomba bov or similar valve? I think the loss of acceleration is coming from a turbo leak, but cannot confirm.
 


Bluedrank

Active member
Messages
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252
Location
Winter Park
#2
Well everything is supposed to sit flush, so that's probably a problem you'll want to get fixed. I'd imagine you've created a bit of a boost leak. That being said, from reading other posts on here, the turbo does take a second to re-spool in between gears due to the vent to atmosphere. The recirculation aspect of the stock valve is supposed to help keep the turbo spooled in-between shifts. So if you remove that functionality, you lose the benefit.
 


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68
Location
Ottawa
#3
Had a similar issue with my BOV adapter. If it's not flush and tight you will have major boost leaks and no power.
 


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186
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57
Location
Dayton
#4
Are you talking about a re-circ valve spacer or the whole re-circ valve? If it's a factory re-circ valve from an R56 they're junk. You're better off with the factory Fiesta re-circ valve as it is a piston type and does not have membranes that will tear like the Mini valve. Also, the non-jcw Mini maxed around 12psi on a good day (maybe 16 in overboost) so the spring may not be strong enough to hold the higher boost on the Fiesta.
 


OP
F
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11
Location
Orlando
Thread Starter #6
So... I figured out what my problem was: the included screws for the BOV are a few millimeters too long, which caused it to not be flush. I bought new screws and it was finally flushed. I feel slight power back, but not "glue to your seat" power. Top tip to those whom bought the Mini Cooper BOV: buy shorter screws.
 


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8
Location
North Wales
#7
The recirculation aspect of the stock valve is supposed to help keep the turbo spooled in-between shifts. So if you remove that functionality, you lose the benefit.
That literally makes no sense since there isn't a 1 way valve on the intake. Any pressure that 'recirculates' when the TB is closed will just reverse air flow out of the intake. I'm sure it is so minor and not noticeable but I can't see how it would make you spool faster.
 


Bluedrank

Active member
Messages
676
Likes
252
Location
Winter Park
#8
That literally makes no sense since there isn't a 1 way valve on the intake. Any pressure that 'recirculates' when the TB is closed will just reverse air flow out of the intake. I'm sure it is so minor and not noticeable but I can't see how it would make you spool faster.
I'm just repeating what everyone keeps saying in regard to these things. I have no idea personally.
 


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