Ok so I am almost convienced I am suffering compressor surge now.

When I let off the throttle I used to hear a flutter. I shortened my intake recently so it pretty much sits right against the compressor. Now under boost it's ridiculously loud.

The only way I can see the noise getting so much louder from shortening the intake is the fact that the air is being pushed back out through the compressor. Which mean my BOV is opening fully or at all.

My motor is at 21 in/Hg at idle so according to this I need the unpainted one.
(I currently have the white one)
http://www.tialmedia.com/documents/w3_tial_bov50_sp.pdf

However if my BOV isn't opening now wouldn't buying a higher negatve PSI spring make it even harder for the BOV to open. Based on the symptoms wouldn't I need a lower negative psi spring.

I have a video of my Vacuum/Boost gauge reaction to letting of the throttle which may help. I will upload it tomorrow.

Thanks ahead of time. I really want to resolve this ASAP. I am not willing to retune and turn the boost up until I have this fixed.

 

Try a lighter spring?

 

the heavier spring will make it harder to open. i think you should keep the 9lb spring. at what boost pressures are you getting "surge" i think many people confuse light flutter under low boost with surge. also where are you sourcing vacuum? and how are the lines ran?

 

I get it no matter what pressure it is hitting. The higher the pressure the louder the surge. I never get a clean blow off at any psi. The preliminary tune was only done up to 11psi.

I am sourcing the vacuum from the vacuum block which sources form the vacuum manifold.

The line is ran directly from the BOV to a port on the vacuum block attached to the firewall.

It just doesn't make sense to me that a spring that is lighter than what they would recommend (based on my vacuum at idle) won't open at all. Its' driving me nuts.

 

The change in VACUUM is actually pulling the spring open, not the pressure release from the turbocharger. That is why it is based upon the vacuum of the car in order to select the correct spring. If its driving you nuts, get the right spring, or continue to argue the logic all of the time, and continue to go nuts..

Its weird, I know, but going to the right spring will help the problem.

 

I know it's the vacuum pulling it open. Kind of the reverse of a wastegate (push vs. pull), but if it can't pull it open with the spring in it now. Why would a harder spring be pulled open by the same vacuum. I don't mind buying another spring I just don't want to buy one and have it not fix it, and then buy another.

 

yea hondas like lighter springs compared to their chart. if you dont want to buy a new spring and wait for it you can always cut it. thats what i did with mine. i cut like 2-3 coils out of it. and it fixed the problem. idleing the diaphram in the bov should be about half open under vacc.

 

You have no idea how much I appreciate this direct answer. I will be ordering the lighter spring and cutting the one I have in hopes it works until the new one gets here.

 

actually i wouldnt even order one. a cut spring will work just fine. as long as you dont cut it to short. start by cuting 2 coils out of it and see if that works. heres how much i cut outta mine.

 

^Dude you are the freaking man. Thank you so much. Which spring was that?

 

no offense but that is not the proper way to solve your problem. run the proper spring. there is no reason the 9lb spring or 11lb spring shouldnt work

did you cut your oem springs to lower your car too? that is just ghetto

 

Ok for starters cutting a BOV spring until my new one gets in to allow proper function of the BOV isn't a bad thing. There is a difference between cutting a BOV spring to reduce the spring rate and allow it to open properly and hacking apart a part of your car to screw it up and put yourself at serious risk. I will be ordering the black one which is as light as it goes, but until then I want the BOV to do it's job.

 

lol? no. how is cutting a bov like cutting springs to lower your car? haha.

im just saying in his case cut the spring and if that fixed the problem then he can order a new one if he wishes. nothing wrong with a cut spring. it will do the same job and will still seat correctly too. and like i said hondas like lighter springs. nuff said.

 

Call/email Jake from Tial. You should be able to ship your spring to them in exchange for the one you want for just shipping charges.

 

it was the unpainted one. -22 in/hg.

 

I cutted mine. Work 10x better than before with the uncutted 11lbs spring. People can say what they want. If it work than it work.