lets have a technical discussion

[Reed]

So im addicted to the internet and have nothing to do and it has been a while since we talked about anything worth talking about in this here forced induction forum. So i guess if anyone has anything worth talking about let it out.

I guess ill get started...


Um.. so how about them dang variable geometry turbos. they's somethin else huh. anyone feel like splaining how they work.

[sv650s]

now that's something i'll like to find out, i'm still down there learning about bi-turbos

[beef_bourito]

what are bi turbos, whenever i heard of xcar biturbo, i always thought it was another way of saying twin turbo.

[sv650s]

bi turbo, it's a twin turbo but one works on lower rpm's and the other one starts working when the engine rpm gets higher, the other one starts to work too. it's the german's way of reducing turbo lag

[beef_bourito]

oh, so it's a different way of saying sequential turbochargers. ok.

[beef_bourito]

ok so it's another way of saying sequential tubochargers.

[sv650s]

pretty much (at least i think so). have you found out anything about the variable geometry turbos? i really wanna know about them

[beef_bourito]

they have little flaps in the turbine (they look kinda like teardrops) that shift to make the diameter of it either bigger or smaller and to direct exhaust gases towards or away from the turbine wheel. they are controlled with a diaphragm that senses the boost presure and it moves the vanes. the advantage is that you can have a quick spooling turbocharger with good top end efficiency.

[Reed]

are the flaps actually on the turbine or are they in the turbine housing? i just dont understand how they can make the vanes in the turbine move when its spinning at 100k plus rpm.

can someone find a diagram of how the diaphragm actuates the vanes?

[Moppie]

Originally Posted by sv650s

bi turbo, it's a twin turbo but one works on lower rpm's and the other one starts working when the engine rpm gets higher, the other one starts to work too. it's the german's way of reducing turbo lag

No, Bi literaly means 2.
So its a 2 Turbo set up, it has nothing to do with how they are set up, and can be sequential or parrallel.
e.g. the Maserati BiTurbo uses a Parrallel set up with one turbo on each bank of cylinders.

[TurboGSR96]

yall see that electrically assisted turbocharger mazda has been testing on the rx-8, it uses an electric motor built into the turbo to spool it at very low rpm.....like 1500, that would be cool but I dont think it would be realistic on a turbo the size of lets say a SP 74 or a GT42 any big power turbo, any feedback

[sv650s]

does nitrous decrease gas mileage? i figured no since all it does is make the gas burn more richly and cools the incoming intake air that it has nothing to do with the fuel system.

[Reed]

nitrous leans out a motor not richen it.

[sv650s]

no i mean it has more oxygen so it makes the gas burn more richly

[Alastor187]

Originally Posted by sv650s

no i mean it has more oxygen so it makes the gas burn more richly

Maybe you should try explaining what you mean without using the words "rich" or "lean" ;-)