How are we having this discussion when OP doesn't understand what VGT is?

 

Omg, OP just went full retard....

 

your understanding is wrong.
re-read what they do.

 

Because we all are obviously envious of the OP's awesome 500rwhp build.

 

Ha, maybe I am....sorry if I mis interpreted. I'm about to leave but I'll read up more later......

 

You've already established yourself as an abrasive and useless person in general. And I didn't say anything mean to you in my response but you choose to take it there, probably because you are a wal-mart person.

You're lack of good sense shows in your response. Since I know the schools are slacking in teaching your kids good English and syntax I'll go ahead and tell you what you are trying to say:

"Of drift cars that swap a v8, those that do it, do so for the response."

Funny how you jump on my for comprehension, and then quote yourself. If you take the time to really pick apart what you typed, you actually said,"most drifters are running v8's." But hey, we all know comprehension isn't your strong suit.

 

you do know there difference between a compressor wheel and turbine wheel right?

and you do know that surge has everything to do with the RPM and PR of the compressor wheel right?

and you do know that if you spin the turbine faster/earlier, the the compressor wheel also spins faster and build boost sooner, possibly building boost to the left side of the surge line and becoming very unstable?

 

Wait, BJ is a drifter?

....Well played sir, well played.

 

I thought we established that on his intro thread.

 

Wait. Serious time.

18psi please tell how a 30r+ could see 25psi at 2000rpm in 5th? On a miata motor Without flat shift or any tricks. Even with the best fuel i am not sure it is possible.

 

It wont, obviously.
It will try, and surge like a motherfawker.

This is me in a 3076 miata on e85 running *ALL OF IT* in 5th gear at low rpm (filming buddies bp-t festiva vs skyline)

he wasn't even flooring it at all, and listen to how bad it surges.
when he got on it at 2k (different time) it sounded like a friggen sprinkler head and car was shaking violently.

 

So wait is the lack of exhaust flow/low rpm that causes surge or what exactly...

I know it's not enough rpm on the compressor but say we do find a way to keep it spinning... then what?

 

No, I think you've gotten a bit mixed up on what surge is.

Surge is when you have high pressure and low mass flow out of the compressor. If you look at a compressor map, it is basically when you go to the left of the surge line on the map. It happens when the turbo is spinning fast enough to deliver more air than the engine can take in.

 

Which causes a breakdown of the airflow through the compressor. Its like an airplane wing stalling. The compressor is a wheel of wings.

Wikipedia takes this mostly in terms of a jet turbine engine, but the concept is the same. http://en.wikipedia.org/wiki/Compressor_stall
It looks a lot more violent in airplanes.

 

Exactly. Another way to look at it is air is quickly alternating between moving through the compressor normally, and getting forced through the compressor backwards.

Severe surge can potentially damage compressor wheels pretty badly too.

 

antisurge housing ftw

the big bitch in my avatar never surges.

 

If you've never experienced it, compressor surge is pretty horrible.

 

Soooo we need something to allow some of the flow to escape so the turbine can spin at a good rpm?

 

That could potentially help. If airflow through the compressor can be maintained, the AoA on the blades will be effectively reduced warding off a stall condition. Jet turbine engines have a vent valve in the compressor section for this purpose.

 

Wait, what?!?
No, no, no...
If that's how they worked it would be the magic bullet. It strictly helps spool.
The solution you want is right above...

How come I feel I'm wasting my keystrokes?