STi BOV

WANGAN_X · Post by **WANGAN_X** » Wed Jul 27, 2005 6:37 pm

evos have problems with VTA BOV's, do STi's have the same issue?

Post by **Sabre** » Wed Jul 27, 2005 9:01 pm

We can go 50/50 without too many problems, but once you go 100% atmospheric, you need engine management. lol, 100% is kind of fun though, you throw a fireball between shifts

Mr Kleen · Post by **Mr Kleen** » Wed Jul 27, 2005 10:10 pm

I've been thinking about getting one and doing something like a 70/30 split. bring out my inner ricer... what can I say, I love cars that make noise.

Post by **Sabre** » Wed Jul 27, 2005 10:19 pm

Mr Kleen wrote:I've been thinking about getting one and doing something like a 70/30 split. bring out my inner ricer... what can I say, I love cars that make noise.

Says the dude who owned a Civic Si....

Mr Kleen · Post by **Mr Kleen** » Thu Jul 28, 2005 9:53 am

as I was posting that I knew somebody would bring up the fact that I used to own a Civic.

I loved that car, the 2000 Si was an amazing car for $18k, and the shift action was as good as the base model 2000 Porsche 911 I drove for a day. Honda has yet to make a better Civic (but I hear one may be on the way).

[/endrant]

WANGAN_X · Post by **WANGAN_X** » Thu Jul 28, 2005 10:34 am

do you have idle issues, stalling? anything with 100% VTA

also what is the Mod Path for an STi, I imagine it is slightly different from a Evo

zaxrex · Post by **zaxrex** » Thu Jul 28, 2005 12:40 pm

While idling the bov is closed so it wouldn't matter. When you slam the throttle body valve shut after putting the engine under load, the BOV vents to the atmosphere. The ECU had already calculated for that air and is expecting it to be there. You run rich between shifts, and if you have a bad base map or poor tune, that could make you stumble.

The real problem comes in when you increase your intake path with a larger volume system. There is more mass of air there that has to be ejected, and the effects are magnified.

I would believe that if the EVOs are having similar issues, then it is also running a MAF based system like the Subaru.

Post by **Sabre** » Thu Jul 28, 2005 3:02 pm

Zak pointed out the problems perfectly

Mod paths for engines in WRX/STI's are generally (properly done

* Engine Management
* Exhaust
* Injectors/Fuel pump/Turbo
* Intake/Intercooler - Not really needed until high HP levels or to avoid heat soak

WANGAN_X · Post by **WANGAN_X** » Thu Jul 28, 2005 3:41 pm

properly done huh?

didn't you get your cbe before your EMS, BTW how much boost can you run with the Hydra?

any BOV's work well with STI's?

my friend wants one

he want HKS SSQV or gReddy type s/r

i tried telling him that he doesn't need one until he gets a MBC but he wouldn't listen.

Post by **Sabre** » Thu Jul 28, 2005 4:14 pm

WANGAN_X wrote:properly done huh?

didn't you get your cbe before your EMS, BTW how much boost can you run with the Hydra?

any BOV's work well with STI's?

my friend wants one

he want HKS SSQV or gReddy type s/r

i tried telling him that he doesn't need one until he gets a MBC but he wouldn't listen.

I actually did DP/Headers/UP and then a few days before getting the EMS, put my catback in. I never pushed it hard with the catback in though till I had my EMS put in. I'm running 17.5PSI right now and about 94-98 IDC.

Don't ask me about the BOV, I'm still running the stock one

zaxrex · Post by **zaxrex** » Tue Aug 02, 2005 3:14 am

For most apps, a BOV is for show/sound. The stock ones do a perfect job. When you need to start venting double or tripple the volume at +5 to +15 PSI, you will outrun the stock BOV and get compressor surge. By that time, if you are doing things in sequence, you will already have a EM system and a TMIC or FMIC to go along with your larger turbo. That is where a 50/50 or 100% ATM BOV should be used. Only my opinion.

Post by **Sabre** » Tue Aug 02, 2005 12:22 pm

zaxrex wrote:For most apps, a BOV is for show/sound. The stock ones do a perfect job. When you need to start venting double or tripple the volume at +5 to +15 PSI, you will outrun the stock BOV and get compressor surge. By that time, if you are doing things in sequence, you will already have a EM system and a TMIC or FMIC to go along with your larger turbo. That is where a 50/50 or 100% ATM BOV should be used. Only my opinion.

FMIC should be here in a few days BTW... which brings up an interesting question... How the hll do I keep the BOV as quiet as possible. I know Darrin said he had a quiet one, so I might be buying the same as he has.