Blow off Valve

Turbizmo · 06-21-2007, 11:11 PM

I have a problem with my 420a turbo eclipse. Well my blow off valve "XS POWER" does not blow when I am reving my engine; although when I am boosting it can hear it clearly. The BOV has one vacuum line the vacuum line is connected with 3 other vacuum lines. I have the BOOST GAUGE and the FPR and the BOV connected on the same vacuum source the one close to the TB. So i basically have 3 Ts on one vacuum source. The reason for this is that i could not find other vacuum sources. So any idea why my bov is acting like this. forgot to mention I let my brother test it on his Miata turbo and he didn't have this problem it just work perfectly so any idea?

Shadow98 · 06-21-2007, 11:57 PM

I don't belive it's supposed to open, by just free reving. My did the same thing. Never had a problem with it while driving either.

BigRand · 06-22-2007, 12:11 AM

yeah, your not really putting a load on it under free reving it...some go off some don't.

Turbizmo · 06-22-2007, 01:46 AM

Quote:

Originally Posted by BigRand

yeah, your not really putting a load on it under free reving it...some go off some don't.

Why is it that on my brothers miata it goes off while he revs his engine and it goes off loud and on my car u cant hear anything ?

BigRand · 06-22-2007, 04:09 AM

you might have a leak between the TB and the bov. Is your bov welded on or are you using an adapter?

I know when I had the standard HKS bov off the star turbo kit, you could barely hear it, but when I switched to my type S.....it goes off a little bit all the time. Although you can tell the difference when I have a load or not.

Locke · 06-22-2007, 08:54 AM

The MSM factory IHI ball bearing turbo is appropriately sized to its' application and spools quick. The turbo Miata's cam's are also ground for a turbo application from the factory.

Compare that to the slightly larger than needed S16G sleeve bearing turbo we generally use with our factory NA cams, and you will see why we are less likely to produce boost while free-revving the motor.

Turbizmo · 06-22-2007, 03:42 PM

well I have no leak although when I am boosting I can hear it clearly; its pretty loud in my point of view and yes it is welded on to my pipe.

Blitzeclips · 06-22-2007, 04:49 PM

Quote:

Originally Posted by Turbizmo

well I have no leak although when I am boosting I can hear it clearly; its pretty loud in my point of view and yes it is welded on to my pipe.

Theres nothing wrong with it. It's not going to open with free-rev's. Free revving is bad for your motor BTW.

My buddy can do it in his WRX just fine, but I can't. Different cars, set-up, etc.

There's nothing wrong with your BOV. Of anything, it just needs adjusting.

totaleclipse_05 · 06-22-2007, 09:51 PM

Why would you want to blow off free revving anyways? I call people ricers who do that lol.

Turbizmo · 06-23-2007, 10:13 PM

Quote:

Originally Posted by totaleclipse_05

Why would you want to blow off free revving anyways? I call people ricers who do that lol.

Its just cool my xs power BOV i think its not adjustable because when i loosen the spring it wont go off well i guess my 420a its acting stupid

so i guess ill just leave as is but i really cant do anything about it

link16 · 06-25-2007, 10:13 AM

Why do you need to free rev? It is a waste of gas and it shows other people that you have no clue what you are doing. Never build an engine unless you can handle it, by free reving it, you cannot handle it. Your car, thank God I don't do that to mine, it cost me too much.

and while driving you put load on the crank by engauging the clutch and thus causing more load on the engine, making it possible to boost higher.

Turbizmo · 06-25-2007, 01:54 PM

yes i know i was just wondering why other people can do that and i thought my car had something bad because it didn't do that but its coo and i know free reving is bad but yeah thanks CASE closed.

XMasta19 · 06-25-2007, 03:43 PM

your car is broken...that's why you can't do it.

[/end of thread]

Turbizmo · 06-28-2007, 10:42 AM

Quote:

Originally Posted by XMasta19

your car is broken...that's why you can't do it.

[/end of thread]

it is actually broken i broke the handle bar on the passenger side

Slippi84 · 08-27-2007, 01:05 PM

I dealt with this just before I got rid of my 6 bolt I had a huge debate about this in another thread. The thread was more about where to hook up your manual boost controller but the main argument is that by t-ing into your bov line you have a slower reacting and less effective blowoff valve and actually put more wear on the turbo. Now while I was on the side of the peopl that thought it was bs I later moved my mbc to teh compressor hosuing and off the bov line and the bov sounded louder and seemed to be a little more responsive it was fine the other way but did seem slightly better the other way. My suggestion either find another vaccume line or get a vaccume box.