wastgate chatter

[Prof]

Cheers Kev - btw is that turbo running the engine or the other way around !

[oldone]

Heheheheheheheheheheheheheheheheh......:god :evillaugh :cool

[kev-yorks]

Here\'s a cutaway of the ported shroud prof. Lowers the efficiency of the turbo slightly but means that the surge line moves way over to the left on a compressor map.
 
Kevin

[Prof]

It\'s not going to make much of a dent in the power that thing must be able to provide.  I like the idea of that though - it makes a lot of sense - bit like a built in recirc valve.

[efiniste]

Please correct me...but am 100% positive that Rice WAS running BNR stage 3\'s with no BOV. Now looking along the lines of Garratt TO4Z

Sorry, you\'re wrong. I can\'t get on to Ausrotary at the mo\', it seems to be down but I don\'t think he\'s even got the BNR specced engine in yet (he didn\'t at the beginning of December anyway). I think the T04Z is for a different car as he\'s trying to keep the SP close to stock.


Just realised I sound like a stalker! I\'ll stop now.

[88GT-R]

Sounding a bit of an Anorack myself.......

[CraigN]

ported shrouds also make the turbo sound like a jumbo jet is about to take off :god :god :god :god

[yamaster]

is there any BOV or dump valves that sound like the chatter sound??  

[rx mad]

The upmarket BOV\'s are tunable for pressure Prof also the some of the bigger turbo\'s are now coming with ported shroud compressor housings which may help.
Here\'s a pic of the ported shroud housing instead of stalling the air bypasses via the ports in the shroud four of them around the compressor wheel and back into the compressor to keep everything spinning.
Kevin

jesus h thats a big turbo were did he get that of a jumbo jet

[88GT-R]

No...he\'s just showing off!!!!

[syrill-sneer]

I\'m sitting on the fence here, but the reason the rally cars don\'t use BOV\'s is because they use anti-lag, so the turbo stalling is not a problem.
Also remember reading somewhere that the F1 cars in the 80\'s use to blank the wastegates off during qualifying and throw the turbo away after qualifying. Anybody willing to try this?

[Jimjitsu]

sorry to bring this one back from the dead but i have this chatter noise and i have a bov fitted should i try to adjust my bov to eliminate some of the chatter noise as it really is very very load

[rico2k_uk]

your bov is sprung too hard, loosen it off a bit and it should help. if not, the spring may be too hard.

[Matt_K]

sorry to bring this one back from the dead but i have this chatter noise and i have a bov fitted should i try to adjust my bov to eliminate some of the chatter noise as it really is very very load

IMO, and after reading these posts I\'d say you only *need* to eliminate the chatter if your on stock twins... If you\'re running a single, it\'s a matter of personal taste.

I\'m absolutly gutted tbh I have to run one on a RX7. (mine has uprated twins).  I hate dump valves with a passion.

John (88-GTR), with refrence to your post about shaft sizes... you wouldn\'t happen know the shaft size on a 200SX T28 would you? I\'m from a SX background and on both mine I ran perfectly fine with no BOV @ 15psi & I\'ve never heard of a single failure put down to that cause. I\'m guessing they must have a thicker shaft. Infact with them, I think more people have problems fitting large bore exhausts causing low backpressure and dragging oil through the rear oil seals...

[RedRummy]

thank you! this is an interesting discussion, but at last someone has answered my question as to why i have both!

Mine chatters on low boost (I mean if I lift off early, rather than control the boost) but sounds like a normal psssssshhhhhtt when driving hard..  

no idea if its OPk to do that though...  :confused: