less boost with W.W
Senior User
Joined: Mar 2006
Posts: 171
Likes: 0
From: Houston, TX
Its the way it is designed that creates less boost. I have some pictures of the stock wheel vs the WW in my gallery.
The difference is made in the geometry of the vanes.
Stock: 9 vanes (same height) lower pitch (more vane surface area)
WW: 10 vanes (alternating in height) and a steeper pitch (less vane surface area)
These factors result in the stock wheel spooling slower and producing higher boost pressures vs the WW which spools faster and has lower boost.
The steep pitch of the WW vanes allow it to force air out to the walls of the compressor housing faster, meaning you get a faster spool up time. The downside to this is that with the steep pitch and alternating heights of the vanes, the compressor wheel must spin faster in order to maintain the boost level. This limits the ammount of boost pressure that you will see with the new wheel.
In order to correct this you must make the compressor wheel spin faster, this is accomplished in various fashions. One of the easier and cheapest is to shorten wastegate rod. This holds the wastegate shut for a longer period of time, setting off a chain reaction. Your exhaust wheel spins faster due to more exhaust pressure, thus your compressor wheel spins faster bc it is connected to the exhaust wheel.
Hope that wasnt too confusing....
WB
The difference is made in the geometry of the vanes.
Stock: 9 vanes (same height) lower pitch (more vane surface area)
WW: 10 vanes (alternating in height) and a steeper pitch (less vane surface area)
These factors result in the stock wheel spooling slower and producing higher boost pressures vs the WW which spools faster and has lower boost.
The steep pitch of the WW vanes allow it to force air out to the walls of the compressor housing faster, meaning you get a faster spool up time. The downside to this is that with the steep pitch and alternating heights of the vanes, the compressor wheel must spin faster in order to maintain the boost level. This limits the ammount of boost pressure that you will see with the new wheel.
In order to correct this you must make the compressor wheel spin faster, this is accomplished in various fashions. One of the easier and cheapest is to shorten wastegate rod. This holds the wastegate shut for a longer period of time, setting off a chain reaction. Your exhaust wheel spins faster due to more exhaust pressure, thus your compressor wheel spins faster bc it is connected to the exhaust wheel.
Hope that wasnt too confusing....
WB
Last edited by wbhinton; Jul 11, 2006 at 08:32 AM. Reason: More detail:
