Need help with Greddy Type S

[JayB98GST]

Does anyone know what I would connect the small nipple on the back of the BOV to? Right now, I'm running it with out the nipple connected to anything, bu I head somewhere that without the nipple connected, you can't adjust the spring and that the valve doesn't open as fast as it should.

 

[FourG63 97GST]

when you took old bov off, wasn't there i hose connecting it to the intake manifold? u look at the pics in the gallery, u can see pics of engines in there.

 

[JayB98GST]

no, the stock BOV only had a hose that dumped the air back into the intake and then one vacuum hose on the back of it. The Greddy BOV has two vacuum nipples on the back and one big one on the front for the intake.

 

[FourG63 97GST]

this should help
http://herpetology.com/dsm/bov.html

 

[GSX]

From VFAQ:

Quote -

The small hose you removed from the stock BOV must be connected to the larger nipple on the anodized cap (closest to the adjustment screw.)
(Note: This connects to the intake after the throttle butterfly and will pull vacuum when the throttle is closed)

The smaller nipple on the cast aluminum body of the BOV may be spliced into the turbo outlet pipe or into the line between the turbo and wastgate actuator. Use the T-connector supplied. This connects to pressure even when the other line has vacuum. This will activate the BOV faster by applying pressure under the valve seat.

The smaller nipple may also be left unconnected. The BOV will operate slower and more quietly. I did not test this mode.

- Unquote

This should answer all questions...

 

[jncbmx516]

the nipple above the return whole is for the vacumm hose, the little nipple in the back doesn't connect to anything, its suppossed to be left open. If you go to greddy.com and look under FAQ's they'll tell you the same thing.

 

[GSX]

jncbmx516,

I'm pretty sure the experience of those that wrote the VFAQ, and mine [as well as numerous others] speak the truth on this matter. I suppose we can re-open this discussion to further opinion.

As for Greddy.com:

Quote -

What is the lower nipple for? The lower fitting is a vent for the internal diaphragm. The lower nipple should be left open and not be connected to anything. Do not plug up this opening.

- Unquote

I find this to be very odd. Wonder if the person was 'new' - ahhhh, probably not.

Well, I guess JayB98GST could always test either way, but I am certain that connecting the lower nipple will cut down on the flutter associated with the blow off valve in its unadjusted form and also help with the speed at which the valve opens since we are talking about using pressure to operate the valve.

Either way, good luck!

 

[Black95GSX]

I've tried it both ways, with the lower connected and disconnected from the vac lines.

With it connected, it was leaking air above 14psi.... but with it disconnected it held 30psi without problems

 

[984G634LIFE]

I was always under the impression that the lower nipple wasnt supposed to be connected to anything at all and the top nipple was to be connected to the intake vaccum line.... i dunno maybe i'mwrong and thats why my car only runs a 13....