Still got the Greddy Type-RS on the car (KA-T, 5 PSI for winter) and this thing is just not opening. Surge, surge, surge. Didn’t sound like it was opening at 7 PSI either, although my friend said it sounded like it was “starting to open” lol. It’s recirculated. This blow off valve was included with the IAP turbo kit.
Tried removing the smaller & tighter spring & loosening the screw far out, which has indeed make the action lighter & smoother by hand. Has never leaked at least.
Since I plan on sticking with 7 PSI or so, should I find another more suitable BOV for my setup or should I go awol on the thing? Has anyone here got an RS that opens everytime, 1-2 PSI, or is it just designed to open after 7 pounds…? Cuz if someone here has it opening easily at low boost i’m just gonna tear mine apart and well…yeah. Stuff.
If I switch BOV’s, please make suggestions. All I need is something that opens at very low boost, holds boost, and will recirculate.
BOV’s shouldn’t have two refernce sources… it’s not needed the primary internal source is always the IC pipe, the primary external input is attached to the manifold the spring is there for retention and return when the T closes the pressure differential between the IC pipe and the manifold force the BOV open… that’s it, simple. (Unless there is some magical need for a greddy BOV to have a secondary external input source like a boost controlled WG).
You BOV may not be sitting in a place where it’s getting enough flow to open, the piston may be jamming up or the feed line source on the manifold may not be in the right spot. thier are ALLOT of reasons why it won’t work, start with cleaning and honing the surface of the BOV piston and piston sleeve. then look at where the external reference line is connected. change up the location see if that works… next take a look at the placement of the BOV on the IC pipe… frankly the typical Blitz location right next to the turbo is WRONG… it’s convient for the OEM setup , but it’s WRONG… you should never let boost pressure build up throught your IC. so if your BOV is on the hot side of the IC move it to the cool side.
mikeness - There actually is no smaller nipple on the type-RS…just a “weep” hole to receive atmospheric pressure (see bottom link). Only the S had that…
BAS - Hot side or cold side, it’s supposed to be opening. It’s location is quite far from the turbo. It’s right before the intercooler, on the hot side, it should definitely be sufficient and good to help catch the surge sooner. I think I may take a look at the internals again to see if it needs some working in. Perhaps try getting a larger diameter/shorter vacuum hose for the source too, maybe.
Any other thoughts? Or users of the RS?
As a side note, i’ve done SO much searching on this I might as well share some cool stuff on the RS:
You mount it too close and your going to loose the maximum ammount of pressure in the system.
Allow the system to build up some back pressure and it will surge the manifold once the TB plate is opened again… your method will require that the system rebuild pressure all along the IC system, unless it’s a V mount then it’s allot of volume to refill…
I’m using this same BOV on my sr with a greddy front mount IC mounted on the hot side and it opens up just fine. It was actually leaking a little bit at stock boost (BOV was set at the softest setting) so i tightened it up a little and it works perfect.
Although I thought about coil-cutting, I figure it pretty much kills the BOV’s resale value if I decide to start using another one and sell it. Would be ideal to find another way around this…
I’m going to get a huge vac line and run it shorter than the current setup. This should be done anyway…
That said, I may feel brave (read: fed up lol) one day and start “trimming” the spring. I have a feeling this would work, i’d just like to avoid it unless it becomes totally necessary. I’m certainly not going to change the blow off valves’ location, the only downside to it in my mind is accessibility.
pearlS13 - that’s exactly how I figured it should work…it’s just never released it seems, loose or tight.
HEy man let me know,
my car is now away for the winter and I can maybe let you try out my typeS, it opens up at very low boost on my SR (HOT PIPE) so it should work for you.
Are you revving it up in neutral, or is this while driving?
Some BOV’s are designed to resist like 30PSI.
There was at some point a rule of thumb about BOV placement, something like 8" away from the TB, but that doesn’t really apply if you’ve got bends or really sketchy piping.
Really though, at 5-7psi all placement is going to do is change the sound LOL
Are you sure it’s a real GReddy BOV that worked in the first place? Those IAP kits are pretty sketchy-looking. If there’s a tear or an improper seal in the diaphragm, it will never see vacuum and never open.
It’s a real Greddy RS BOV…having carefully disassembled and reassembled it, we would have likely noticed a seal issue. The performance of the BOV before & after the stiffer spring removal remained the same.
Benson, I may just take you up on the offer! I just want to try a few things first, which might take a while given the cold weather and stuff. The vacuum source hose to the BOV is kind of long, I want to shorten it and perhaps increase the diameter a bit (part of Sasha’s suggestion).
if all else fails take your intake mani off drill a hole and tap in a nipple and run it straight to the bov. if that wont open it i have no idea what to say, i would think a larger turbo would have more momentum, and closing the throttle plate would cause an even GREATER pressure surge than a smaller turbo (which theoretically would be able to slow down much faster) so your bov should really be opening even at low boost.
It seems a lot of people have been having trouble with the type RS. I have a feeling it was designed for lancers and WRX’s more than anything that all run 1bar+
I’ve seen it on an S13 running 7-12psi and it only started making an audible blow off around 10psi so im thinking that may be the issue.
Then theres the bings Type-S’s. those things never worked right from the begining!
I’ve shortened the vacuum source hose (comes from FPR/Gauge/FMU tee) with no change. Greddy RS/turbo is still surging at 5-7 pounds. As stated above the screw is on the loosest setting and only one spring remains.
As Benson is aware, i’ll be trying his Type-S on my car at some point in the next week. He’s got it adjusted and working to open at low boost apparently. Will be interesting to see how it works…
If it works plug & play on my car, maybe the RS might’ve just been a wee bit too “hardcore” for my setup lol. If not, then maybe i’ll try using the brake booster as a vacuum source, or looking into something else - given that something in my setup would most likely be causing the problem.
I suggest removing it and opening it up to clean. My friends BOV was causing really bad comp. surge, we couldn’t figure it out. Finally we took it apart and disassembled it, it was all gummed up and the piston wouldn’t move. We cleaned it, lightly lubricated it with sewing machine oil and she worked like a beauty.
I was working all afternoon with the Greddy RS and Type-S. What a frickin’ day. I ended up using the Greddy RS, I wanted to from the start (the Type-S is lent - THANKS BENSON!!).
The type-S, upon plug & play installing on my car, was releasing literally about 1 second after letting off the throttle. A quiet release, weak, and a trailing ssss turning into a whistle. Stalling was bad too. We were going to adjust it some more but the RS seemed like it should be working (and it’s mine), so we focussed on it instead.
Upon setting up the RS to vent for the first time on my car, we had a vacuum reading of -6 starting it up! Wonderful! I could finally tighten the bugger down!
It ended up requiring actually replacing the second spring inside again, AND tightening of the adjustment screw. With this done, it was finally venting (and doing it’s job) for the first time ever.
The Greddy Type-RS sounds awesome!! And it’s releasing right around 0 on the boost gauge (no surge). So yes, it can be setup easily for lower-boost/earlier-release. And the several-tee’d-FPR vacuum source appears to be working perfectly.
2 key issues remain now:
– Venting makes the idle a bit funny, and wants to stall a fair bit more.
– Recircing helps the idle but sounds to be compressor surging again…100% surging. As in no matter how it’s adjusted, it seems to surge. And it STILL wants to stall out from time to time…it’s almost as though the recirc fitting can’t flow enough air or something. :dunno:
The vacuum source hose to the BOV is kind of long, I want to shorten it and perhaps increase the diameter a bit (part of Sasha’s suggestion).