i had my stock plastic bov swapped out for a metal oem one. my boost guage after swapping the bov's shows the peak boost holding 1-2psi higher? what would cause this to happen? i turned down the mbc but curious what could cause this.

 

The plastic one leaks.

 

ok thanks..

 

I think there should be a preface on "the plastic one leaks" comment. OEM stock boost it doesn't leak. higher boost it may leak

 

Not always true. Mine only held 16psi after about 30,000miles. put a ix on and its fine.

 

The plastic one sucks!!! I mean leaks....found that out on my 2g Eclipses. Even at
stock boost.

 

Your problem fixed, stocker leaks for sure.......Everybody agrees - case closed

 

You bet your *** it does. You just can't see it.

 

We tested one on an 03 Evo when the Evo's first came out. At 8 psi you could hear a small leak, at 13 psi it began to leak a fair amount, more than you would want. These things are well known for leaking since the 2G days. This is the main reason for people using the 1G BOV.

 

I pressure tested mine, too, and the valve opened at 13psi. Then, my JDM MR DV didn't open all the way up to 24psi.

 

^^^ what he said...those are the numbers I saw as well.

 

My plastic one leaked just by blowing into it. Damn bean counters!

 

Plastic sucks metal is better