sti69

iTrader: (1)

Hi Guys.

As above now completed,just taken car for a spin with the original air box fitted. My question is now its running with the oem air filter the external BOV (Blitz type) is now quiet and does'nt WHOOOOSH as loud now . You could hear the BOV when you lift off before you hit full boost and now you only hear it when you hit 7psi of above (max at 17psi)

I've checked all the pipe work and everything is fine. So all you tech heads out there is this normal! The car is pretty much standard (MY94 STi).

Cheers

Gutmann pug

I would have thought you would here it everytime you change gear and are on boost and when you let off while on boost......

sti69

iTrader: (1)

True, just wondered if anyone has gone back to oem filter box and noticed any difference with the BOV. In theory the sound should be the same but in practice its not! Its boosting to the same psi but the BOV is not as noticable

Gutmann pug

Bet it sounds more grown up though and thats no bad thing

JCScooby

who wants to grow up.?.....

Gutmann pug

anyone who has a DV for more than 6 months generally

Steve Whitehorn

iTrader: (13)

Yes I noticed exactly the same with a 94WRX a few years back.
I also found it strange.

But recon you are best off with the standard filter as you are less likely to have MAF issues.

Stu Smith

As far as I knew the whooshing you was hearing before was air being forced back out of the air filter, you wont hear it with the oe item. (Someone please correct me if Im wrong tho!)

Stu

sti69

iTrader: (1)

You could be right there mate, thinking about it...although the BOV is venting off i guess some of the boost pressure will back feed into the turbo and vent through the induction kit but with the oem box there's more volume and so will quieting the noise...i think

And i think this is my 100th post - yippeee

Stu Smith

I dont run a VTA BOV or induction kit on my P1 but on my old 200sx I ran both and got the noises you are getting. I think its as you say........the BOV doesnt clear all the charge air so some gets pushed back out of the air filter. Mine used to do it mainly at lower revs when the dump valve wouldnt be quite open.

Congrats on the 100th post!

Stu