MajorCB

ANOTHER Forge thread I knowwww

ok, so my Forge comes in the mail.. all it has with it is the main unit, green spring which was already installed and the yellow spring.... no screws... is that normal? ...

and as far as the install goes... I know people keep going back and forth on the spring color... but is there any REAL break down as to what spring to you use based on the amount of boost pressure a person is running? or are people just winging it... I would like to go with the Green... but the sticker on the yellow did mention that it may be used for higher boost pressure.

I just want to do this right and not have any issues down the road is all.

thanks for your help!

BPacak

go with the green. use the stock screws. and make sure the opening is facing down when you put it in.

MajorCB

just curious as to why it needs to be facing down... any particular reason?

BPacak

otherwise it would be facing nothing.

MajorCB

I guess I'll see what you mean tonight when I install it

vahdyx

iTrader: (7)

Don't over tighten the bolts either. My yellow springs and forge spacers should be in soon. I'm gonna try both and see what I like better.

Also you should lube it up too.

MajorCB

what did you use for lube... man it sounds funny talking about lube like this haha...

and I dont plan on over tightening at all... and will use the stock screws... and aim the opening down... I assume the vacumn hose is a direct fit.. does the hose line from the Forge point down or up? .. not sure of its orientation

BPacak

doesnt matter where the hose points just make sure you have the clamp on there good.

MajorCB

I assume you used the factory clamp from the original diaphram's hose?

BPacak

yup

MajorCB

cool.. good deal.. thanks!

MajorCB

sooo.. I installed it... vacumn hose on the outside... plunger on the inside facing down... turned the car on... no problem... took it for a short drive... didnt even get out of second gear and maybe 5-lbs of boost and bam! felt like the car lost all boost instantly with a loud pooosshh sound.... turned it around and started driving back and had little to no boost capability at all but heard more whistling.. turned the car off, checked the vacumn hose, no issues everything still looked in place... do you think this is a spring issue? green too weak? or did I install it correctly?

help!

BPacak

hmm sounds weird. try unhooking the battery for a few mins and if that doesnt work try switching springs.

MajorCB

can a spring be in backwards? or does any direction matter... and why disconnect the battery?

BPacak

so the computer can get used to it or whatever, think you should do it for every mod you put on.

Edubs

OP, see image below. The red arrow show's where the bypass needs to face and why...

ronn

iTrader: (3)

Sounds like valve might be stuck in open position. hard to say. Take it off and install it again. it's NOT the spring! Keep green one in..yellow is too much.

ronn

iTrader: (3)

He would still build boost if it was facing up...know what i mean? It would only effect blowing off.

MajorCB

ok.. will keep the green one in... I did lube the inner plunger with some high temperature grease... just a tiny bit.. do you think this had anything to do with it maybe too?

and as for the installation in the downward facing position... I made sure that the opening to the plunger was facing downward.. its like at a 140degree angle if you can imagine that...

BPacak

i didnt lube mine up. pretty sure it already came lubed.

Edubs

I didn't post the picture to diagnose his issue. He simply asked earlier in the thread, why face it down. Picture explains it best...

apicia

iTrader: (2)

I don't know if it matters which way the Forge goes in. It is not tight like the stock BPV. As for the spring, too much boost can push that valve open, correct?

MajorCB

OK!!... well... yall are gonna laugh.. cause I know I did... in my haste to discover what if any differences there were in the new BPV..... appparrrently, I didnt sinch down the Charge pipe clamp down nearly as tight as I should... and so... POP... it came off... thus no boost!!... ... sooo once I DID get it back on "tightly!" I drove it around again and all felt good.. 5lbs 10lbs 15lbs.. and then 21lbs... all felt good.. no no real sound difference what so ever really.. probably because I am running a stock intake... kinda feels like the stock unit was just about as loud.

soooo... yeah.. you can say it... "Dummehh!"

thanks everyone though for your assistance... was planning on starting over at step 1... got the bolts tightened down to jussst past snug.. no stripping this time for me! sheewww!

SSlobalt

I think it has boost pressure holding it in from the coldside pipe and has vacuum pulling it open from the manifold, via a solenoid, but I'm kinda drunk right now.

ronn

iTrader: (3)

BPV 101
Boost and vacuum go through the same hose...modulated by the solenoid. However, boost pressure is also pushing against the valve from the other side. The spring (stock and prolly green) has 8lbs pressure always pushing against valve. At full boost you have EQUAL AIR pressure on both sides of the valve..pushing it in through hose and out from turbo side. The added spring pressure insures this *tug of war* is lost by the turbo pushing it out because of the added 8lbs the spring provides. So, the valve stays firmly shut under full boost.
On lifting off throttle, a rush of vaccum is introduced (maybe solenoid helps cut boost still in the hose?) into the line leading to BPV (vacuum line) and it overcomes the spring pressure to open the valve..dumping and recirculating trapped boost (with the throttle plate shut)..thus preventing unwanted surge. This is the function of the BPV..making sure you don't trash the turbine shaft with constant surge.

Personal note: I use stock BPV and always will...not knocking Forge.