The APS is actually very quiet; not sure what you are basing your assumptions on. Look at the reviews of the APS unit vs. Forge; you'll definitely see that the Forge has many more issues comparatively speaking.

 

I was about to say the same thing. If you want sound, dont got APS. If you want a bov thats gonna do the job and not flutter, get a APS

 

I swapped my Forge RS BOV for an APS unit, the results was a much nicer streetability, no more fluttering, hold boost with no problem but I think it makes a little bit of noise (I had a drop in filter and stock airbox).
As soon as you have a cone filter, recirc DV or APS BOV will make noise anyway.

 

I will post an update when I buy and install the APS. Hopefully the flutters, sputters, and partial throttle gremlins are all gone.

 

if they aren't you've got something else going on it's a fantastic bov and will likely allow you to get back to enjoying your evo again, I know it did wonders for me.

 

i will add to the list of ex Forge RS users.....replaced it with the aps twin and all partial boost issues gone. car drives like stock at 31psi. buy it.

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my stock plastic valve was leaking so i replaced it with a aps. it was really quiet at first but when i put a cone filter i was shocked out how loud it got. aps has been holding 26psi for 3 years with no problems.

 

My APS was good, and then my car started bucking between shifts. This became a huge annoyance for me because I need steady state cornering and throttle control. It made the throttle a "buck" switch.

I swapped it out for a metal 9 DV. No more bucking whatsoever! Then I went 23 psi, and the 9 was leaking boost. Ever heard the POP at 7500rpm followed by a huge buck? That's your BOV/DV not holding boost, or you have a significant boost leak.

A good friend who knows a thing or two about turbo systems showed me how to mod my metal 9 DV into a BOV by sealing the little hole in the DV and then drilling another on the side of it. Has been holding boost perfect ever since, and is probably the most wicked sounding BOV (even though it's fully recirculated) that I've heard.

 

i have the Aps twin vent..its great. And no it isnt that loud.

 

Well I am sold on the aps! I just installed my ets intake and already have the apexi filter, but with the stock mr bov I do have serious fluttering @ 23lbs.

 

I am using the Forge Recirc BOV (BPV?). I flutters and bucks like crazy during normal driving. The unit only seems to be happy if I am completely off boost or at full throttle. It is possible that I am using the incorrect spring/shim combo, but I am too lazy to take it off and change springs 10 times just to make it work.

This weekend I plan to put the stock BPV back on until I get around to purchasing the Forge RS model. I have heard of better results with this unit. If not then I will try the APS, but I don't know if I like the idea of some of the exhaust gases venting to atmosphere.

 

not to get geeky, by design the best BOV is the HKS. The synapse is similar in design. But, people have always complained about the HKS. I will be running a re-circ'd HKS and if that fails will switch to synapse.

I have witnessed the forge do exactly what is being described above. I have experience a greddy type-s leak boost above 23 psi as well. Both were on a 2005 Evo VIII.

I also drove an Evo with the APS twin vent and was incredibly impressed. If my ETS pipes were not flanged for HKS, I probably would have gone with APS.

EDIT - APS is much quieter than forge, so don't look for the sound value. Its a quick vent and while it can be heard, not that loud. In the 23-25 psi range, sound wise forge has been the loudest and yes, it was re-circ'd like all the above mentioned.

 

I fail to see how 2 ports for venting, one of which is only used for when you build high pressure (run high boost) can help with everyday driving....?

All you need for driveability is a softer spring. So if APS is better for driving - it probably just has it by default. On a Forge RS you can actually adjust it, where it can be made soft for everyday driving or hard for when you race and want to keep all your boost.

Yeah i know you will say APS holds high boost just fine - you have no way to find out. It will be the same boost on your gauge but you may be overworking your turbo compared to a harder spring unit.

my 0.02

 

The vent feature of the APS is adjustable as well, but many choose not to use that feature, mine solved all my part throttle problems and i have it adjusted to vent very little.

 

i personally like the GFB Stealth FX. never had an issue with it - holds boost and makes some noise without any idling issues.