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Jim_1979
03-02-07, 22:46
Been looking at a Blitz DD bov, and the seller states that it can handle 18psi, 1.2 bar.

What would happen if you were producing more boost than this?? Would the dumpvalve just go pop??
bondango
04-02-07, 01:42
Been looking at a Blitz DD bov, and the seller states that it can handle 18psi, 1.2 bar.

What would happen if you were producing more boost than this?? Would the dumpvalve just go pop??

Thats using the standard Internal spring, if running more boost just order the uprated spring part no. 14099A which will hold 2bar, only an extra tenner or so
Homer
04-02-07, 01:58
Or buy an adjustable DV like the HKS SSQV
bondango
04-02-07, 02:10
Darryl i think the SSQV has been redesigned now and has no adjustment nut on the back (fakes do though). Personally i would opt for the Tial meself.
Homer
04-02-07, 02:39
Darryl i think the SSQV has been redesigned now and has no adjustment nut on the back (fakes do though). Personally i would opt for the Tial meself.

Mine is 3 yrs old but your comment explains a thing or two. One of the loal guys had what was supposed to be a brand new SSQV but there was no adjustement screw at all despite it being a genuine new HKS. First time I've heard the design has changed.

Tial has been highly recommend to me in the past, though the cheap-as-chips XS power Sard copies seem to work very well on the singles. They cost bugger all at £40 or so.
bondango
04-02-07, 02:48
Agreed on the XS copy of the Tial, Used one on a gt4 build and never got a bad report back about it. Ive also ran 2 x SSQV copies on a 300zx and after 2 years they still working fine - £60 for the pair.
The SSQV is in itself built to take high boost anyway, due to the twin champer design, first chamber being used for low boost. So i guess they realised that the adjustment screw wasnt really neccessay.
Homer
04-02-07, 03:03
Perhaps this deserves a new topic, but how come I get compressor stall when lifting off from anything less than 0.5 bar?

Surely thats because my SSQV isn't doing its job?
Jim_1979
04-02-07, 08:27
Thanks for the replies.

First of all, where would I get the blitz uprated spring from?

Secondly anyone have a link to the tial/xs copy bovs where I can buy one?

thanks.
Jim_1979
04-02-07, 08:33
What do people think about the turbo xs bov on this page (bottom left, the type H one), any good?

http://www.xs-power.co.uk/shop/index.php?cPath=33&page=2


Also, what would happen with the blitz bov if it ran over 18psi, would you simply hear air escaping or something?

Edit: Just bought the blitz DD, but I need the uprated spring now. Having a look about. Can see them in the US etc, but not UK.
bondango
04-02-07, 11:02
Perhaps this deserves a new topic, but how come I get compressor stall when lifting off from anything less than 0.5 bar?

Surely thats because my SSQV isn't doing its job?


Are you taking the Vac source pre-throttle body or manifold? a little stall isnt an uncommon thing as not 100% of the positive pressure is released by the Bov, and some does revert back towards the Turbo. Also Bov placement can have an effect, i.e. BOV placed nearer the TB or one place just after the Turbo.
It is a topic for discussion though, as you say the SSQV was designed to operated on a low and high boost responce.

http://www.hksusa.com/products/more.asp?id=792
bondango
04-02-07, 11:05
What do people think about the turbo xs bov on this page (bottom left, the type H one), any good?

http://www.xs-power.co.uk/shop/index.php?cPath=33&page=2


Also, what would happen with the blitz bov if it ran over 18psi, would you simply hear air escaping or something?

Edit: Just bought the blitz DD, but I need the uprated spring now. Having a look about. Can see them in the US etc, but not UK.


Any Blitz UK dealer should be able to get it for you without any probs.
The spings works like a wastegate spring in theory, in that its tension is set for a predetermined level, if you run 20psi, the pressure will overcome the spring tension and forice the valve open, in essence causing it to leak of excess pressure over 18psi
wkdtime
04-02-07, 12:38
Perhaps this deserves a new topic, but how come I get compressor stall when lifting off from anything less than 0.5 bar?

Surely thats because my SSQV isn't doing its job?

You should'nt be at that boost, i put it to your DV not dong it's job.
Gamer
04-02-07, 12:52
The new HKS racing type 2 BOV has the adjustment screw on it. This BOV is touted as being able to hold high pressures and is rated to hold 800rwhp. I am running one on my car now.
Ian C
05-02-07, 00:25
Homer, perhaps your BOVs spring is done up too tight and not opening.

Or you hear the ch-ch-ch-ch noise of it opening/closing in a loop and have mistaken it for turbo stall (or "wastegate chatter" :rolleyes: )

-Ian