Agreed, you should never want to hear the shuttering sound! I don't even understand why one would want to hear the "whoosh" sound of a BOV dumping to atmosphere or even more exaggerated by one of the models with the horn on it.

 

This is better:

 

Funny!!!

 

While watching the Duck quack video, the next video that popped up from Synapse was quite interesting. They suggested that the BOV should be open always at idle. Not for blow off, but to help eliminate stall characteristics from intake restrictions caused by turbo and pluming restrictions. I notice that George D is the only person I see with this BOV. I am going to do some more research on this! The video was quite convincing.

 

Anybody watched this video before?



Very interesting.

 

Curt, I'm not sure how the BOV you have is constructed on the inside, however, I just had my Forge (bought from LR) apart recently,
and it appears that no matter which way you hook it up, there will be pressure from the pre-throttle body pipe applied to open the BOV.
If you have it connected like zerMATT from the first page of the thread, there will be greater force to open the BOV than if its connected
the opposite way. There will be some force either way. This is because the pressure is applied to the outer parts of the piston (see pic 3)
rather than the top of the pistion. Its like one of those piston/pressure problems back from thermodynamics.

PS: I apologize for the huge pics.

If BOV is connected in typical manner, boost pressure acts on a surface area of the outer diameter (41mm) minus the inner diameter of the piston (23mm)

total area: 1320mm2 - 415mm2 = 905mm2

If BOV is connected according to Curt's method, boost pressure acts on a surface area of the inner diameter from pic 1 (20mm) there is a beveled area
on the housing which is why this is not equal to the 23mm from the first scenario.

total area: 314mm2

So the question now becomes, is it preferable to have a larger surface area for the pressure to act on (typical setup) or one that is 3x smaller? (Curt's method)
I for one am going to put my BOV like Curt suggests for a time to see if there's a noticeable difference. I am also trying to alleviate my car from other noises
which I think the BOV might be a factor in (see other thread)

Don't want to throw fuel on the fire, just want to provide more insight.

 

Curt:

Did you have a chance to look at the Synapse video? I would like to hear your opinion on this theory/setup. Thanks.

 

That's considerably different than the bypass valve I'm running, and I don't think the old bypass valve that was on my car when I got it (PO said it was Forge, but I don't recall any markings on it) was quite like that either. I'll see if I can find my old valve, take it apart and see what it looks like. I remember the bottom of the piston being cupped, but I don't recall the side profile of the piston. If I had that valve, I'd be inclined to bench test it to see how much pressure it takes to open it from either direction for a given spring pressure. If it does indeed operate in either installed orientation, I'd still run the lightest spring pressure possible. Because of the different surface areas, spring pressure wouldn't be the same between orientations. Did you take into account the increase of surface area from the bottom of the piston being concave?

As such, if the Forge unit does operate in either orientation, I apologize for the misinformation. I was unaware of the stepped piston allowing boost pressure to either side. I only took my own personal experience into account and was speaking solely on that information. I would still recommend to anyone installing a new valve to take a few moments to familiarize themselves with the operation of the particular model they have and install it accordingly. I would also like to mention that the generalization that all valves can be installed in either direction is inherently false.


I did watch the video, but I'm not sure I understand the gist. So his bypass valve is normally open at idle, and at tip-in, he's sucking in metered air until boost rises to close the valve which allegedly reduces turbo lag. I'm not sure I buy it, but I think I can simulate the action of his valve with mine. I already have mine adjusted really low, but I might be able to go low enough to let the valve sit open at the first stage opening (my valve is a two-stage unit, but is plugged to only allow full-bypass on both stages).

 

Curt the valve pictured above is identical to my evo unit and again I was told to run it in normal orientation. So those with evo units yours should be as pictured and as Curt said should be ok either direction

 

I have done quite a bit of research on this now. Your description of function is spot on, however their claim to fame is the incredibly high actuation speed of their valve, more like high speed solenoid. I doubt you can make normal piston BOV act quite as fast, but please try and let us know the results. This design did win SEMA, product of the year award. When I get back to the US, I will buy one and see if there is any improvement. The only person I know with this BOV is George and he has nothing but the best of everything. I will have to send him a PM.

 

Not that I have ever had an issue with my BOV or at least I did not notice it, but the design described below truly does look like a better design:

Since Synchronic BOV is a piston actuated BOV, the question has come up whether or not it needs servicing with every oil change. Or perhaps it wears out over time and stops working as well as when it is new. The piston BOVs and DVs that are out on the market today, unfortunately have generated this false impression about the Synchronic BOV.

Synchronic BOV is a little bit long in dimensions because we specifically designed around this problem. In blue is the valve and the piston is in red. As you can clearly see, the piston is located in its own chamber. The valving mechanism is an actual valve that doesn't require lubricant. Existing piston designs have the actuating piston in communication with all of the airflow. So that with each dump of the BOV, there is lubricant in the system that gets discharged with it. Synchronic BOV does not need to be re-lubed since the actuating chambers retain all of our proprietary lubricant. The lubricant does not evaporate or fade over time.

And for those of you that may be wondering about the part of the piston that is exposed to airflow, there is a wiper in the mechanism to save lubricant and that surface gets lubricated with each stroke of the piston.

I guess I am lacking in maintenance as I have never lubricated by Forge BOV.

 

Curt:

I found this short write up, again need to test the theory, that he claims has been tested all ready.

Problem #3: Design a BOV that would stay shut under high vacuum Something told me not to worry about this too much until later. When I first started to test the prototypes of the design, I couldn't get the valve to stay shut under heavy vacuum. When it would be shut at idle, the BOV wouldn't open. And when it would be open at idle, it would work perfectly between gears. I kept fighting it and fighting it, until I finally gave up and conceded to the design. Little did I know later that this was one of those discoveries of serendipity. Beta testers began to report better throttle response. What? I started to look at how that worked and, guess what? It makes sense. By bypassing the restriction of the turbo, intercooler piping and all the surface area of the intercooler, you do get better throttle response when coming off of vacuum. And they also started to report better fuel economy. ? So testing on the dyno started to show that cars were able to hold the same RPM and wheel speed with less horsepower and torque. So this just isn't a "defective" feature to fight, but instead embrace. Instead of going for the ricer noise that we all secretly long for, we need instead to re-circulate the BOV inlet/discharge and run a cone filter to get the noise.

 

Interesting concept, and I'm open to try it. A bit spendy though - I think we'd use part number DV001A.010, which is $270 on Amazon. If this weather ever lets up, I'll see if I can emulate it at all with my bypass valve short-term, and might look into Synchronic myself. It's hard to tell much from their video with the valve pulling in unmetered air on an unloaded engine.

 

Yes, not exactly cheap, but not out of range for most with these cars. I think I paid more for my Tial that I might swap for this upon return. Still need to contact George and get his opinion.

 

Do you remember this thread

https://rennlist.com/forums/944-turb...***-valve.html)

I tried to explain it to you then.
You should always take in information properly instead of having an ignorant attitude.
You are falsely giving the illusion to everybody that you are in the know regarding recirc valves.

Virtually all recirculation valves are designed to work TO GIVE THE SAME RESULT in either direction.

You are right that the weakest spring possible is best (up to the point that your car could have a slight stumble/drivability issue at moderate acceleration; if too weak a spring)

At idle or very low load it will not matter one bit if the valve is open.

I happen to run the synapse valve, currently. It too can be run in either direction although the design is different than most, and renders an ever so slightly different result (phone their tech line if you want to know more) It's a very solid unit with very smooth valve action (unlike the Forge), but I honestly can't say it is worth the extra $.