Forge bypass problem

[ByrdMan23]

ok so i ordered forge a while back and they forgot to give me the blue spring(which is what everyone recomended) so while i was waiting for the spring i used the yellow with 2 shims and it seemed to work well.. at that time i had a injen cold air which i recently sold and just got the new nano installed. I tried the blue spring with one shim and my friends said that when i gunned it i black smoked so bad. continuos flow of black smoke... i am quite sure there is no leaks on the intake and everything was installed correctly..

Isn't the yellow spring the proper spring for ms3's? according to forge yellow is 15-23 psi which fits a unaltered ms3's boost.. I am just baffled how so many people say they use blue but when i use it i run WAY to rich and shoot out smoke... any help?

and i know this has been beaten to death but im concerned about people who don't have intakes and they say they are using blue, because with out a intake its hard to hear if there is any fluttering and i wonder if they are making their cars run even more rich

 

[Speed3Rookie]

You are fine with blue.
The black smoke is normal.
I was running the blue with two and recently switched to yellow with 1 shim.
Hold boost just fine.

 

[ByrdMan23]

I know that white smoke is when you want to worry but when it comes to my cars i've always felt that NO smoke is always the best way to go...
I actually switched back to the yellow with 2 tonight and it was to dark to see if i was smoking so i guess ill see tomorrow... but it makes me feel better that someone else uses the yellow

 

[spdjnke]

Keep the spring tension low, it will hold boost regardless. If the spring is to tight it will cause you a crap load of headache down the road, I found out after talking with the guys at TurboSmart the best tension on a pull type bov/bpv is to have it the lowest possible and it has worked beautifully for me, turbosmart and my previous Forge unit.

 

[AutoEuphoria]

black smoke is just extra gas...these cars run very rich on the stock tune to be as kind on the motor as possible.

 

[tru-boost]

what spring/shim combo you use has nothing to do with smoke or ryour air fuel ratio. no matter what you put in that valve, when you are in boost it seals shut and you AFR will be the same no matter what.

 

[ByrdMan23]

what spring/shim combo you use has nothing to do with smoke or ryour air fuel ratio. no matter what you put in that valve, when you are in boost it seals shut and you AFR will be the same no matter what.

I tried blue with and without shims and yellow with and without but heres why i think you are WRONG looking at it from two angles...
the first is easy.. i put my stock one back on and no smoke
and second the spring does matter becuase if less air is going back through the system because the valve is closed shut due to the high tension of the spring you will not be getting as much air.. the car runs rich.. just like if u used a bov vta... red spring is for 30 plus..my car doesnt have enough psi to push that spring NO AIR!
i havent messed with it anymore since i posted this but im gonna try the green spring... according to forge green is for 5-15 (which with a shim or two should equal exactly what ms3's push stock boost, lower gears around 10 and higher right at 15...) yellow is for 15-23 which is a little high...
i still dont see how people are using blue(23-30)

 

[ByrdMan23]

thanks spdjnke...and auto euphoria i know what you mean.. ive looked at brand new mazdaspeed 3's and just from when the dealer drove em off the trailer their exhaust is pitch black... however before the valve i never had black smoke shooting out my exhaust, these cars run rich but not THAT rich...

 

[patty AT forge]

I remember talking with you via email but don't recall the name. So I can't look to see what we've gone over.

"and second the spring does matter becuase if less air is going back through the system because the valve is closed shut due to the high tension of the spring you will not be getting as much air.. the car runs rich.. just like if u used a bov vta... red spring is for 30 plus..my car doesnt have enough psi to push that spring NO AIR!"

Your understanding of what's going on is just a bit off. VTA valves cause the engine to run rich not because of less being recirculated back into the intake, it is a result of air escaping from the system.

Think of it this way: You are catering a dinner party at a meeting hall, there is a person at the door counting attendees (air) as they enter the building (this is the MAF). These people are walking through a foyer (intake before the turbo) and through a revolving door (turbo) into a hallway (intercooler piping). And from there through a set of doors (throttle body) into the meeting hall (intake manifold).

Occasionally the door into the meeting hall is closed (this is when the throttle body shuts). Ideally if there are too many people in the hallway the excess will take a small detour through a side door (bypass valve) that leads them back to the foyer. And when possible head back through the revolving door, down the hallway and into the hall. That would be a recirc setup. And when all is said and done we have the proper amount of food (gas) for the number of people (air).

Now in a VTA setup that side door is replaced with an exit (blow off valve). In the above scenario people exit that door and head back through the front door and are recounted by the doorman (MAF) resulting in more food being delivered to the hall than is actually needed.

In your hypothesis there is neither a passageway back to the foyer nor an exit. This would result in a backup in the system but the amount of air metered should still be correct.

All of that is irrelevant though if you have a problem. My guess is, barring some sort of odd occurrence, that you have a leak. If it goes away with the re-intallatin of the OEM valve it is safe to assume the problem lies with the Forge valve.

Here is what you should check:
*Is the cap tight?
*Do you have an o-ring sealing the valve to the intercooler, and is it free from tears?
*There are three o-rings in the valve, are they in good shape? (Do this by pushing up the piston with your finger or a pen, while it is lifted cap the small port on the valve cap with your finger and release the piston. The piston should drop about halfway and stay there. If it slowly drops or falls all the way from the beginning one of the o-rings has failed or the valve need more grease. I usually do this 10 times in a row to make sure.)
*Is the recirc port snug on the 28mm side port of the valve? Sometimes the factory tension clamp isn't adequate for the job and a worm-drive clamp is needed.

 

[08_MS3_GT]

i started with a blue spring and two shims --> no smoke
i recently switched to a yellow spring and two shims --> no smoke

 

[ByrdMan23]

patty...
I would think the fact that a tougher spring not allowing air to go back into the recirculation system would be close to the same as a VTA setup...If the air can't push the valve open then it does't go into the recirculation (less air,too much fuel) I Understand that VTA is completley escaping from the system but i woud be willing to bet if you did dynos with each spring there would be a difference in ATF ratio...

I appreciate all the help though.. I'll take a good amount of time checking everything and if all else fails ill just sell it to someone..

 

[tru-boost]

but thats where you are wrong.even if the spring forced the valve totally shut and it NEVER opened it would not be like VTA. with VTA the air that went through the MAF is lost and ruins your AFR. with the recirc system in place that air never leaves the system. if the BPV is open it just keeps recircing but eventually gets in the manifold. if what you are saying happened and the stiffer spring kept the valve closed so it couldnt recirc the car would still be fine because that air then goes straight to the manifold and is not lost to the atmosphere like VTA. and there is no change in afr no matter what spring. if you run 18psi its 18psi no matter what. if there is no leaks and everything seals the results will be identicle.

 

[08_MS3_GT]

patty...
I would think the fact that a tougher spring not allowing air to go back into the recirculation system would be close to the same as a VTA setup...

not really, or at least not in a relevant way. those valves are meant to relieve the pressure aft of the turbo so that the pressure doesn't build up in the bottleneck between the engine (off the throttle, not using air) and turbo (grinds to a halt since the pressure downstream spikes). letting the pressure out of the piping permits the turbo to keep spinning (albeit more slowly) instead of instantly decelerating which induces excess wear. you can also get compressor surge, which is where the turbo not only decelerates but reverses direction --> VERY bad.

BPV's and BOV's both accomplish this, and the preference of one or the other is often based upon how the car was engineered. ECU controls have fueling expectations given what was initially designed/installed.

 

[patty AT forge]

Any luck on what I recommended checking? One other thing is to make sure that the manifold reference line is tight on the nipple located ont eh valve cap.

Here is what you should check:
*Is the cap tight?
*Do you have an o-ring sealing the valve to the intercooler, and is it free from tears?
*There are three o-rings in the valve, are they in good shape? (Do this by pushing up the piston with your finger or a pen, while it is lifted cap the small port on the valve cap with your finger and release the piston. The piston should drop about halfway and stay there. If it slowly drops or falls all the way from the beginning one of the o-rings has failed or the valve need more grease. I usually do this 10 times in a row to make sure.)
*Is the recirc port snug on the 28mm side port of the valve? Sometimes the factory tension clamp isn't adequate for the job and a worm-drive clamp is needed.

 

[tru-boost]

also make sure the valve is tight on the flange itself i have seen a few where they have come loose from there. all you need is snap ring pliers, or even needle nose pliers do the trick.

 

[RichB]

so should we be using the yellow spring if we're under 23 PSI?

 

[Rotus8]

so should we be using the yellow spring if we're under 23 PSI?

I recommend that.

 

[RichB]

So gathering what I read in this thread;the performance should be the same with yellow but the turbo will like it better. Any way to tell it is dialed in correctly?

 

[08cosmic3]

I have been using the Blue w/2 for many months now. At the time the general view was that the blue with 1 or 2 was the way to go. Has this changed? Post your spring setup please. I'll start

Blue with 2.

 

[RichB]

I've run Blue with no shims for a while and changed to Blue with 1 shim a few weeks ago.