forge bpv recommendations?

[skrappyyy]

I'm running testpipe + cbe + cai, I was wondering what you guys would recommend?

[Hypnotized]

Try blue spring one shim.

[mazdaspeedster3]

Is that what you are running Hypnotized?

I am running the blue with 2 with intake, inlet and MM. Winter time I run just blue no springs. When I got my Forge BPV Forge recommended blue with two.

[GoFast]

do a search. I am sure someone has a very similar set up and I am sure you can find on of Paty's posts on what he recommends.

From paty at forge:

Ok this is my cut and paste reply when ever I get asked this question:

The springs are used to account for variances in atmospheric conditions, and the relationship between boost and vacuum that different cars will see. To simplify it greatly the more boost that you are running the stiffer a base spring pressure you will need to compensate for the pressure differential between the manifold and the charge piping right at initial boost onset. Cars with few modifications running at or near factory boost seem to respond best with the yellow or blue springs. Cars running a bit more boost the blue and a few shims. The red spring is best used on cars running upper teens or low twenties.

That out of the way let me quickly go over how to adjust the valve. I recommend using three different spring tensions and performing some real world testing. Say for instance the yellow, blue, and blue with shims. Drive normally for a few miles (part throttle shifting, stop and go, merging and passing for some wide open data) then do a few wide open throttle runs. Do this with all three setups and compare the results, with "seat of the pants" or with data logging. If there is no difference use the softest setup. If the middle seems best that is the setup to use, if the stiffest works best perform the same tests with the next stiffest and compare.

That is the more complex answer. The easy quick answer is "use the blue spring if the cars is modified, if the car seems sluggish add two shims to the valve". 95% of the cars out there using the valve are using the blue spring.

Hope this helps. Let me know if you have any other questions.

[Hypnotized]

I am running blue with one shim and I have a sri, inlet and test pipe. No issues at all.

[mr_mazda329]

I'm using just the Blue spring...see mod list.

[koston33]

just blue spring. only mods are ms cai, and ap.

[karl hungus]

just blue spring. only mods are ms cai, and ap.

(five-0) search police.

blue no shims.

[leadf00t]

I have been running blue+1 since last fall, with & without my SRI, and have had no problems at all.

[skrappyyy]

(five-0) search police.

blue no shims.

I did a search, but no one had any real specific info as to what they were running with a cai intake testpipe + cbe.

I read on the other threads that mention, fluttering at low boost levels is supposed to be good?

[mr_mazda329]

Fluttering is bad. The air is then surging back into the turbo

[funksilver07]

I've basically tried them all, (yellow, blue, red) with and without shims. I always end up back to blue with 2 shims. I initially was running a catless DP/RP, SRI, TIP, and used red (no shims) for a while. When I switched back to my stock DP/MP set up with my current mods the blue with 2 works for me. Experiment for yourself, every car will feel a bit different, depends on your car and how you feel it's running...

[boosted1]

Blue spring with 2 shims and CP-E Nano SRI(S&B Power Filter).

[coyfish]

<<< blue + 2 shims

[08cosmic3]

Blue w/2

[ms6acton]

blue

[PCspeed3]

So if im running 17.5 psi on the cobb stage 2 map I may want Blue with 2 shims? I have Blue spring with one shim right now and it seems to work fine...

[zaka]

Someone could tell me if this is a compressor surge or flutter on this video (3th gear, part throttle):

http://www.youtube.com/watch?v=iyKZ_ZBwM20

I use the red spring (it seems hold better than the blue+2 shims). I couldn't hear the TIIING sound of my Forge with the red spring. On full throttle, it's like a CHIINNG sound lol
My mods: SRI, TP, ETS and Piasini Tune. I hit 21-22 PSI and settle 18PSI.

[Timshadi]

Not quite sure? Anybody else have idea??

[zaka]

I've tried again blue+2shims, and it's quite the same sound (maybe flutter) on the video but plus the TINK sound.
So red spring is OK or not for my setup (huh)

[patty AT forge]

That would be flutter. Engine vacuum alone is enough to open the valve with the red spring so ****in theory**** it is fine for any set-up and boost levels on these cars.

In practice it is a bit more complicated. Ideally you do not want flutter but if tuning out the flutter leads you to use a spring that is too soft then the trade off is slower boost response and potentially lower boost levels.

Think about that for a second... what is causing the increased spool time and the boost to lower? Its a leak. Now turbochargers are feedback systems. Diverter valves and blow off valves ARE NOT boost control systems. If spring tension is causing your boost to lower than the boost control mechanisms (wastegate, solenoid, etc) are still trying to regulate boost to that higher level. This means that your shaft speeds are drastically increased to make the same boost level or in extreme cases LESS boost. This is terrible for turbo longevity and once the turbo ends up operating outside of its efficiency range it can have a detrimental effect on engine life also.

The flutter you are hearing is caused by a pressure differential of a few psi and isn't really something to be concerned with. That being said if you notice no performance difference with the blue spring and shims go with that arrangement. If there is no difference go with the softer set-up.

[zaka]

Thanks Patty ;)

I could feel the difference between red and blue (1 or 2 shims). Red holds really better and built boost is stronger but a little bit slowly than the blue one.
I think I will take the safe mode -> blue+2. less flutter than the red one.
Blue+1: No flutter, but don't hold boost :(

[ericrapp]

I have played around with this for awhile. I am running blue and two. Flutter is what you might hear. as i do. Thats ok.

[Willieville]

how did you guys get the forge open, I tried my hardest to open it, but it wouldn't open. I bought mine from another member (not here) and all I got was the yellow and red spring, the yellow is def not holding the boost I want so I want to switch it out for the red.

[08cosmic3]

how did you guys get the forge open, I tried my hardest to open it, but it wouldn't open. I bought mine from another member (not here) and all I got was the yellow and red spring, the yellow is def not holding the boost I want so I want to switch it out for the red.

I use a large set of channel lock pliers and a peice of leather so not to scratch the BPV. I run Blue spring w/2 shims. Where is the blue spring? Do you have the shims? Try yellow with two shims. You will need the blue spring IMO. The red is mostly for those running high boost. Call Forge and order the blue spring form them, should be cheap.

[Willieville]

not sure where the blue spring is, I think I might try the red for a bit without any shims first and if I don't like it I'll contact forge. now to get into the damn thing!!! atleast it sounds great.

[ericrapp]

Hey there, Willieville. I also push down on the cap when i loosen or tighten. Please remember to keep the internals clean when playing with it. I would suggest the yellow spring with a shim or two first till you contact Patty@Forge. you can pm and you will get excellent service and advice too. 08cosmic3 is giving good advice here. The outer ring will unscrew from the body removing the cap or hat, exposing the spring and shims.