Off Boost Compressor Surge

[Stoffa]

Will do, I prefer less noise, everyone thinks your a wanker with a noisey valve, mine started completely plumbed back but I thought it was messing with things, venting too much air back across the front of the turbo intake.

[Stoffa]

What about placement, would it be better to have one valve closer to the turbo before the air goes through all the pipework and intercooler? or does it not matter?

Would it be ok to use one factory BOV and my existing GFB one, or do I run the risk of removing too much air with that?

[vorigan]

 Stoffa said:

What about placement, would it be better to have one valve closer to the turbo before the air goes through all the pipework and intercooler? or does it not matter?

Would it be ok to use one factory BOV and my existing GFB one, or do I run the risk of removing too much air with that?

i prefer close to the t/b as practical and it wouldnt hurt to run both

[Eight_dollar]

Rick mentioned he noted on boost comp surge too - have ya had it retuned to lower boost target in link

[Stoffa]

nah its only when he loaded it up with the brakes, fixing the little niggly things before anymore tuning is done

[boon]

As pl0x and funky said, in the case of the way our cars are built/tuned, it's not a fault in the equipment (I'm running stock V7 BOV plumbed back) it's just the way they're tuned to try to build that boost as fast as possible. You can drive around it - I'm already learning to avoid it, once you drive your car a bit you'll get used to how you need to drive for it not to happen. Oddly enough the car seems to drive a lot better that way too

[Guest]

My turbo I fear has failed. Cant see how anything could have gunked up lines but thought is it possible the comp surge could cause the exhaust wheel to hit exhaust housing? A nasty whine starts as soon as it starts to build boost. Does surge cause wheels to hit? No side to side play. If so I shall have to get that stock bov on with the new turbo.

Hoping steve pops back in...

[vorigan]

major comp surge can brake a crank shaft as for the turbo it can put over 100lbs thrust loading on the thrust bearing so yes it can do major damage

[Guest]

Got a stock valve on the way be here monday. Will put on with the new turbo and pull off exhaust and see how the old one looks. Cheers steve for the quick reply.

[Guest]

Stock on came as a flange but found something cooler. Missus bought me a steve murch one...turned up today so will fit with the new turbo. Any tips on how hard to set it steve?

[Stoffa]

awesome, pics please. my guess is as soft as possible without it opening at idle

[vorigan]

 evowrx said:

Stock on came as a flange but found something cooler. Missus bought me a steve murch one...turned up today so will fit with the new turbo. Any tips on how hard to set it steve?

set what? sorry brain dead

[Guest]

The spring. Pics later when I have a real computer and will know if it is the real deal.

[Guest]

Pulled the vf23 housings off. Spins fine a bit slower than the new one but the old probably has oil in it. Doesnt look like its hit either housing and no side to side play. No filings either. Swapped vf22 in and checked oil feed line before i started it. Runs fine on new turbo and no funny noises.

Any ideas steve? Also checked your facebook as you keep saying to do on here and man theres so much good info on there good stuff.

Pics of bov as promised.

[vorigan]

just try the other turbo and see how it goes, i havent seen one of them in years i also use to make 50mm version and thats 25years ago how time flies

[Guest]

Yea just went for a drive new turbos fine?

[Guest]

I tried a stock valve venting to atmo only because of where it sits and it wouldnt stay shut on idle. Now if I plumb it back into intake and have it on the hotside to keep things tidy will that keep it shut on idle? Ive heard they need do be plumbed back to keep them shut but you hear a lot of things. Just dont want to cut and weld pipes for fun. Getting a whole lot more surge now Im tuned with another 10psi and turbo sounds grumpy sometimes.

[Marky]

It won\'t matter if its open at idle or part throttle - if it\'s plumbed in then its a closed circuit anyway. To be blunt the idea is so long as it closes with boost, it can be open in vacuum as much as it wants, no harm done.

Since you\'ve now gone to MAP sensoring, you could even just chuck a breather filter on the end of the BOV and leave it be like that.

Turbo toyotas (from memory, I had an MR2 briefly haha) are deliberately setup to leak at idle like this, it\'s meant to give (slightly) better economy since you\'re bypassing the turbo at light load if that makes sense

[Guest]

This literally dies to like 50rpm then recovers. Keeps doing that and wont sit on any sort of rpm just opens dies closes recovers. Havent tried it since tune but it only happens on idle fine on cruise.

[Marky]

Oh weird. Sounds like same thing it would do with AFM. When you say since tune... do you mean before the link went in at all and it was on factory ECU? If it was on factory then you\'re just introducing a massive vac leak, if its using the link you could just run it with an open throttle body and it\'d be fine.

Short answer - plumb it in, you\'ll find advice to use hot or cold side of cooler everywhere (I haz no idea) but either way it\'s going to work fine, it\'s how the factory does it afterall.

edit - plumbing it in doesn\'t make it get closed, what it DOES do is mean that it doesn\'t matter anymore if it\'s open or closed at all.

[vorigan]

stock bv isnt meant to vent to atmo they have to plumb back thats why everyone buys crappy adjustable units that casue surge and idling issues

[Guest]

It would be practical on hot side as it runs under the intake pipe dont think Ive got a pic of it how it is now. You recommended close to tb somewhere though i think. The negative pressure will hold it closed though?

Same as this now minus the afm.

[vorigan]

feed it back between the afm and turbo intake

[Guest]

Running G4 no afm anymore. Bov on hot side cause any issues?

[vorigan]

no issues just let it vent stinky linky wont care