BW s476 turbo
08-02-2013, 08:07 PM
#31
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It's the turbine wheel which will affect your spool time. So, if you're going with 92mm turbine as Stock48 recommends, you might as well get the the 80mm compressor. Just a thought.
08-02-2013, 10:02 PM
#37
I never liked that "spools by this rpm" nomenclature. What really matters is the temperature of the exhaust (including pipes, turbine housing, and downpipe). A turbo will spool faster after youve been driving for a while than it will when its first started (even if the engine is full temp).
Also time is important... lets say you are at a dead idle (and have been for a few minutes), the lag to get into boost may be 2-3 seconds. Now lets say you are cruising down the highway and punch it, now the lag may only be 1 second when you nail it.
My point is, turbo lag is not something as easy as "this size turbo will spool by this rpm on this engine". Even what fuel you use makes a huge difference. With that said, most of the mass is in the exhaust wheel, and also the smaller the wheel the more pressure (and heat) it will cause between the turbine and engine and therefor the faster it will spool. More heat + less mass = much faster spool time.
Also time is important... lets say you are at a dead idle (and have been for a few minutes), the lag to get into boost may be 2-3 seconds. Now lets say you are cruising down the highway and punch it, now the lag may only be 1 second when you nail it.
My point is, turbo lag is not something as easy as "this size turbo will spool by this rpm on this engine". Even what fuel you use makes a huge difference. With that said, most of the mass is in the exhaust wheel, and also the smaller the wheel the more pressure (and heat) it will cause between the turbine and engine and therefor the faster it will spool. More heat + less mass = much faster spool time.
08-03-2013, 12:33 AM
#40
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this is anything but easy i can tell you that lol
me and Stock48 have PMed each other alot talking about which turbo/size motor/intake/cam/header pipe... you name it. so its not that im just picking one out of a hat. the more we talk the more we narrow it down on the best setup.
me and Stock48 have PMed each other alot talking about which turbo/size motor/intake/cam/header pipe... you name it. so its not that im just picking one out of a hat. the more we talk the more we narrow it down on the best setup.