Quote:
Originally Posted by IsaacCarlson
Why not use a cutout for the turbo so you can vary the amount of exhaust gases/pressure applied to the turbo? You could set it at a point where it would spin the alt within a certain rpm range. After all, an alternator has some resistance when putting out current. This would keep rpm down some. perhaps we could open the cutout when cruising and close it when driving with variable revs/load? This would keep the turbo rpm pretty stable. Just an idea....
|
you don't want the turbo to go slow or your response to power goes way down, big lag. What you don't want is to get to much back pressure that the turbo is restrictive because trying to keep the exhaust housing A/R small .
What turbo manufactures have done to improve the peak efficiency around wide rpm is .
1)variable geometry exhaust housing, this not used much in gas as temps to high but idea is a variable vanes/deflectors in the housing that can keep efficiency up over engine rpm band .
2) twin scroll housing, this is were the exhaust housing has two different A/R compartments,. one for low speed response and larger for high rpm . there a flap to control when it opens (there still normal wastgate still used) .RX7 used this for many yrs on there turbo 13b engines (87-91).
3)Sequential turbos , this is were there 2 turbos, its similar to twin scroll idea. One turbo is run at low speed/boost and then second kicks in . Later 92+ RX7 went to this system and so did Toyota supra turbo's at end.
There also some work on electric assist turbos which can use the turbo shaft to power systems like alternator .
here link to article on it .
Browser Warning