Got boost now, took it up to 15psi and bugger me its scary. A guy from Link helped me out with values, thats all it was, there was so much more air going through the old map was useless... so, now that boost is on, I am getting compressor surge, I have a Lindsey BOV, so has it maxed out? Waht reduces this surge? bigger IC pipes? bigger BOV?

 

What's compressor surge?

 

Bigger BOV should solve that...what kinda BOV do you h ave? What psi is rated for? I had a generic BOV on oen of my cars and it would give me a half gobble/half blow off and I'd still get compressor surge...If you want a damn good valve try anything Turbo XS ( I run a turbo XS RFL) no more gobble/surge

Does it sound like a turkey call/ gobble?

 

Hi NZ,
Does the surge appears during onset
of boost or at 15psi ?

 

How do you know it's compressor surge?
Technically that would be too much boost for too little air flow under steady state conditions. So, I wouldn't think that it would have anything to do with the BOV. However, a little unstable flow might be expected for a split second when you let off the throttle.

 

"Compressor surge is the rapid flucuation of turbine speed caused by the throttle's being closed under boost." Excess pressure builds up when you shift or let off the gas under boost -- the turbo is still spinning, but the boost has nowhere to go. It usually makes a sound something like a turkey's gobble. Is that what you have NZ? If so, first thing to do is make darn sure your current bypass valve (BOV) is opening fully when vacuum is applied to it. For reference, my stock valve has no problems with 22 psi and 350rwhp. If yours is working properly, but just cannot keep up with the flow you are making (?), then the solution is a bigger valve. I did not think any turbo could outflow a stock bypass at 15psi, but I am no expert on that.

 

Yup, I have a gobble, and it happens under low boost as well, I have a lindsey racing bov, seems to be working as per nornal. So a tial 50mm? does anyone run sequential BOV's? This is annoying... may need to adjust that config on my pipes boostguy!

J Chen, onset and at 1 bar, most I have taken it. Its pretty loud, can hear the bov at very light load, and a few psi into it, its all gobble.

 

NZ,
Or move your wastegate control back in front of the throttle plate, so you don't get excessive pressure there.
Laust, MD. Sc.

PS As you can see I am trying out the title suggeted by you, but it's for this time only.

 

Really? You think that will work? I have been running off the manifold for ages, never noticed this at any stage. I guess the bigger turbo has rooted the crappy LR bov. So you reckon a dual banjo bolt in the IC for both lines, or just one line from there and the other from the manifold?

PS The letters after your name suit you very much.

 

Hey NZ You cd went out just like everyone else's. See the other thread.

 

Thaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaanks!

 

I'm glad I don't know what it is. Thanks!

 

Its a nice problem to have though...

So a bigger BOV, and banjo on the IC pipe and it should be minimised? Also, anyone know of a place that supplies banjo bolts with two ports coming off? I would rather that than splitting the hoses later. Also... which of the components requiring a map signal (BOV, air res for AC, dampener, brake booster, fuel reg etc) can use a pure signal? Ie, can I run a hose from the manifold directly to the BOV, or does it need to be connected to the dampener also? I just want to make use of the two ports I have on ther manifold when I go back to IC boost control config. Cheers!

 

NZ951 you can connect any of the lines you stated directly to the manifold with no problems. I use two BOV plumbed back into the intake and it is a tigh fit getting everything in there. If I had it to do over again I would consider a bigger BOV instead of two. It's just hard for me to get over the big price difference. Since you are having BoostGuy951 make your inercooler pipes he might be able to just weld two pipes coming out to connect the hose straigt to instead of using a banjo bolt fitting.

 

Derrrrrrrrrrrrrrrrrrrrr I am such an ***. I never thought about just welding in a couple of small pipes to fit the hoses. Man what an ***. I dont plumb the BOV into the intake, I will get a tial 50mm unit I think and weld it in. Ok, I am sorted I think! Email coming your way boostguy!