I have been seeing a whole lot of posts/threads asking about "What blow off valve i should buy....why?". I see the same answer time and time again.
ANSWERS in reply to the question (post numbers are sum'ed up on the left):
1) "MOPAR rice plate is FTMFL!"
2-100) Arguing about how the MOPAR "BOV" leaks/does not leak.
-After all the arguing stops, there are a huge list of people that love thier HKS, but when it comes to why they like it so much, they have nothing to say. There is always one smart person that says it has 2 seperate valves that open, but it seems they never show how this happens...hence this thread. Now everybody that can find a search button knows how the HKS works!!
First off, i want to tell you that if you have ever tried to install this bov, you will know that at times it is a little to bulky to fit in those tight spaces....here is a hint: Take off the casing to the valve to get in those tight spaces. (see picture below, if you remove the allen head screws that are marked with red, the cap will come right off, reducing the size by a considerable amount)
Ok, now that i got that off of my chest, on to HOW IT WORKS.
What makes this BOV diferent from others is the basic design. The SSQV is actuated by pressure alterations only, not by the rate of pressure or vacuum in the line, which ensures a quick valve response and complete closure during idle. There is also 2 valves that work together to keep a tight seal under high boost, but give fast response under lower or PTB. (see pictures below)
Above is a picture of the valve(s) closed [ie. acceleration]
Below is a picture of the large diaphram of the bov being pushed open. [ie. when the clutch is pushed in or you let off of the gas] This valve opens when you have been under high boost, and need to dump all built up pressure, but these larger valves can be slow...that is the reason for the second valve! (one more thing you should note is this is not a PUSH type valve, it is a PULL type...but i will tell you a little more about that later)
The picture below is of the smaller valve being pushed open by a pen.
It is hard to see, but the center part of the diaphram moves away from the outer ring of the valve. What this does, is speeds up the process of releaving the pressure, AND begins the pressure relief faster than if just the large valve were used. (very good for keeping your turbo healthy under higher boost levels. almost completely elimimates pressure that causes pressure surges [fluttering form turbo] caused by slow release of boost from charge pipes )
Another thing worth mentioning is the HKS ssq is a pull type valve. This means that it WILL NOT leak from the valve. The pressure from the boost will hold it tightly in place untill there is a change in pressure, then the valves will work accordingly to the level of boost/pressure that needs to be released.
I hope this has helped someone, and i do not advise you take apart your $200 BOV to see exactly what i have shown you.....this is why i used a cheap knock-off BOV to show how the valves work. If you do this on your own (pushing and pulling, using pens to press the valve down, holding valves open with allen wrenches), you may damage the structure of the diaphram causing you new BOV to be useless.
Oh yeah, sorry about the sad m.s. paint drawing.
How the HKS SSQ bov works! W/PICS
Linear Mode
