"The BIG BOV thread" (Where all bov question threads get merged)

[C89ZX7R]

stock turbo on a 04 sti is what ? and whats the cfm rating on it at what psi .

[tayhadar1]

VF-39, don't know know cfm rating but the PSI is around 14.5

[tayhadar1]

And when I say 14.5 I mean that is what it is stock. I also researched but couldn't come up with any very conclusive evidence, but I believe the VF-39 flows somewhere in the area of 500CFM, don't know though

[darylwrx]

sorry about posting another BOV question!! They seem to be pretty frequent around here. I was actually reading some of the problems that they cause (i.e. car running to rich). I am still debating on the first mod i want to do to my car................any suggestions??

i say... uppipe is a good first mod. and down pipe for 2nd.. i have an turbo xs rfl.. i dont have any problem... i have a 04wrx w/4eat trans

[YBNormal07]

You can't find stock numbers for it either strangely enough. From what I've been able to discover, IHI has never released maps for the VF39. Some folks propose that the VF39 is closest to a T3 60 trim,or T3 Super 60. The 60 trim at peak efficiency will flow about 430 CFM buth the Super 60 is about 490.

Turbine efficiency and HP production from a given turbo on a given setup is a very high art form. I tried to get into it at one time but quickly got lost due to a lot of conflicting information out there. You would think simple pump efficiency laws are in effect here, but apparantly this is not the case.

The number I've always used has been 440 as if you do a HP per CFM calculation, this seems to be the average from the change in HP I've seen from various upgrades. Note there is a lot of guesswork when estimating like this, but it seems to hold out pretty good.

[Hytek714]

what about adding a intake system....

[BlkWRXWag]

i say... uppipe is a good first mod

Not on an 06

[vietpunk916]

First mod = catback. Trulely is the best mod for an 06. Sounds nice and ads barley any performance, but on the other hand, you can also be prepared for a downpipe after you fix the solution of not having boost creep. =D Then after catback go get downpipe, then EM. Make sure you find a solution to the boost creep before thinkin about going to Turbo back exhaust.. this is why 3" catback is my only mod for now.

[darylwrx]

Not on an 06

do they have a better uppipe? uppipe is they always says

[BlkWRXWag]

do they have a better uppipe? uppipe is they always says

06's already have a catless uppipe.

[Jhawley]

Ive got it and ive had it for about 3 months now... never had an issue with it and im running stg 2 setup, its makes noise when ur in boost but if ur not in boost you hardly hear it...l guess it depends on how ur driving it

[Slimbolicous]

I am new to the world of WRX. I have been modifing american muscle cars in the past. I have a 02 WRX. Mostly stock except for exhauast from the turbo back. I have obtained a greddy bov from a friend and I want to put it on my intercooler. I noticed the flange on the stock intercooler is considerably bigger that the flange on the bov. All I have is the bov and the gasket nothing else. Is there and adapter plate out there I could use to bolt up the bov to my stock intercooler? If so where can I obtain one. I would rather buy a new top or front mount intercooler with the correct flange than weld a new flange on my stock intercooler if need be.

[02nighthawksi]

Read Me

[geefunk]

dont install a bov on your wrx. Also, since your a n00b I'll let you knwo that there is a search button up next to the new posts button. You can find answers to almost every question you can think of about your car

[Girn]

Here is a video of 2 rex's racing and the BOV's sound nice not like the whistle type sound that I do not like. What kind of BOV is this?