Nice one, I am nearly finished my work week, the 968 handles are properly installed now and I just have to get my panels back on (re-wiring speckers) and then I am nearly done for the weekend! Guess what, I broke my seat when I accererated yesterday! I floored it and the left side of the seat on the vertical seems like it snapped in some way. Weird. Anyone have this happen before? I can feel it is flexing on the left only. Know of a fix?

 

My suggestion for two BOV's was along the lines of using say two of the original Bosche ones (cheap). Just as a temporary fix to ascertain if they can pass enough air so the gobble's gone and the car punches the way you want it to. Would need to fit (weld) other tubes to your main pipes to connect them. If it works you're on the right track.

 

Ok, I tried it with a mates 136db huge BOV off his EVO. I have the exact same result, same noise. The inlet was a lt bigger and the spring a lot stronger, the car was better at idle. Sooooo we had to Maori job up a fitting, but the same port off the IC was used. Do you think the restriction is in the size of the port coming off the IC pipe???

 

HZ,
Did you go back to the banjo
connection as well ?
See, told you it was not the BOV.

 

Yup, went back to the banjo as well, that didnt help in tis config. So that theory out the window for this experiment. It still may be the BOV, dont know yet, we have only determined that it will be at least another variable, the BOV port size of the IC pipe. Does that make sense in flow terms that the BOV would not make a difference if the port is too small?

 

I have a vid of the conquest doin the turkey gobble if any of you wanna hear what it sounds like..

 

That would be very handy thank you Mike! Email? or download?

 

Hi NZ,
Are you running a wide band ?
Was wondering about your injectors.
Are they single pintel type ? Could be
fuel atomisation ?????

 

Not WB yet, I dont think they have anything to do with this problem. Its about venting the pressure.

 

What is the diameter of your IC pipes blow-off/bypass valve outlet? On which IC pipe is your port? You are getting your vacuum signal from the intake manifold, between the head and the throttle body (so that you will have vacuum on the signal line even when there is boost pressure in the IC), right? Have you tried putting putting a T on the vacuum line right where it connects to the BOV to make sure there is not some delay in the vacuum signal (like from a partially blocked or linked line)? Does it sound like this?

https://rennlist.com/forums/showthre...t=gobble+video

 

The diameter of the outlet is the stock size. I have a single line running from the intake manifold (where the ISV hose was, to the BOV, its about 30cm long and nothing T's into it. I have tried the vac connect in several different ways and with different hose. Seems like its the size of the outlet and maybe the BOV

 

We may be going over old ground here, but this statement makes me wonder if we are talking about the same sound. The gobble sound associated with a bad or inadequate BOV only happens when you shift or otherwise let off fast after boosting. Also, if it is doing that with only a few psi (regardless of the turbo), then it can't be just the size of the BOV at issue. A stock bypass in my car is bypassing 23psi of boost with a BB garrett right now, with no gobble at all. Are you sure there are no adjustment spings or shim washers or the like for your BOV? Can you try your stock bypass in the stock (bypassing) configuration, and see how that does? Not trying to be a pest, just rooting for you amd trying to help...

 

Tom, I dont feel pestered at all! I appreciate your help. I tired my mates Turbo XS valve (think it is this brand). I think they must make the Lindsey Racing units it looks exactly the same but the Lindsey Racing unit 50% smaller. He showed me how to shim the spring. The Lindsey Racing spring is very weak and already had washers in it! My mates one was very stiff, he had put washers in it too. I cant go back to the stock bypassing config. So what kind of spring pressure should I be aiming for?

 

NZ, If you are truly interested in informed comments, may I suggest that you post a diagram of your current vacuum/pressure connections relevant for controlling the turbo (i.e. connections to the wastegate and BOV) and update it as you change them.
I, for one, have given up following what you guys are talking about. I have my suspicions, but see no reason to react on those.

Laust

 

Note the BOV is a dedicated vac (no T's).