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I have no idea, why this guy put such a long pipe for the BOV,   im no expert but i would assume since he has to pressurise all that pipe, he has just lost any advantage of doing it in the first place???

Some people, oh well.

http://www.trademe.co.nz/Trade-Me-Motors/Cars/Honda/auction-36440847.htm

Not only that, but it's on the turbo side of the intercooler, not the throttle body side...

Makes no sense at all.

[quote author=GecKo link=board=ForSale;num=1127525144;start=0#1 date=09/28/05 at 11:46:55]Not only that, but it's on the turbo side of the intercooler, not the throttle body side...

Makes no sense at all.[/quote]

Ha i missed that bit, Gecko you over here (from nzhondas ) to get another T2?  ;)

Turbo side of the intercooler actually gives you a louder noise and doesnt waste quite so much of your nice cool air.

I was told that it didn't make a difference which side of the intercooler that the BOV was mounted.

Is there a preformance theory havin't it here?

BOV placement does make a difference

The optimum from a performance side is as close to the throttle plates as possible. This means that no air has to flow backwards to get out the bov and the air is still flowing through the cooler and everything is working like the throttle is open, the only thing is its not.

From a sound perspective the best place is as close to the turbo as possible, this means the bov gets the highest velocity air possible with the greatest amount of turbo sound.

so by sticking it on the turbo side, and sticking a massive pipe in between as well, hes lost performance over standard?

Theres just no room, thats why the long pipie? I'm not going into the BOV placement thing though...

Im not sticking up for the guy, that pipe is strange. Having a big pipe like that increases the volume of the overall pipework, thus increasing lag. Prolly wouldnt make hardly any difference to the operation of the BOV tho.

My theory is that a BOV is detrimental to turbo response anyway.  You're better of without one.

Share your theory then Boosty...

Ok...

You are at full load, full boost, max turbo speed and you change gears and the throttle staps shut.  On a car equipped with a BOV, the inlet piping from the throttle back to the turbo will be evacuated of pressurised air leaving it all at ambient pressure.  When you open the throttle again you have to fill then pressurise this piping once again.  That takes time, especially if you have a decent intercooler.

If you dont have a BOV, the throttle closes at full boost and the air within the pipework has nowhere to go but back through the turbo's compressor and out the inlet.  This can cause the turbo to slow marginally but the energy possesed by the rotating mass of the turbo at 100k+ RPM is greater than that of the retuning air so it isnt as bad as you'd think.  Sure, you will loose some pressure back through the inlet but nowhere near as much as through an open BOV.  So, when you open the throttle again you still have a pressurised intake system and therefor boost avaliable straight away.  This = less lag.
This is why without a bov and  when you have a cooler you get the "cho cho cho cho" sound.  Its air revesion through the compressor blades - the same sound you get as when you blow into one of those cooling fans.

Hope that makes sense - it works in practice - i used to have a blitz valve on my SR20DET and now run none and it is noticeably more resposive...

Its all good and well to run no BOV, but when ur dealing with some higher performance turbos ( IHI VF2X BB) they have ultra light weight comp wheels, having no BOV is a bit of a risk, ive seen the results of a wheel disentergrating and its not pretty to say the least

[quote author=EJ20T link=board=ForSale;num=1127525144;start=0#12 date=10/01/05 at 16:38:07]Its all good and well to run no BOV, but when ur dealing with some higher performance turbos ( IHI VF2X BB) they have ultra light weight comp wheels, having no BOV is a bit of a risk, ive seen the results of a wheel disentergrating and its not pretty to say the least[/quote]


All the pics i have seen of the mugen race version of the T2, which ran 22psi, had no BOV's, just stronger intercooler pipes. So not to much of a necessity with t2's

ime thinking of ditching the bov when i set up the t2 with my front mount,and keeping the airbox so its totaly legal and those nasty cops cant defect me
but i am rather fond of the old pppptttttssssssssss sound :-/