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When you go with bigger turbos, you have to give up something to gain something, i.e. more lag or boost coming in much later, in exchange for higher overall boost and hp.

What I don't get is what you lose with high-lift aggressive cams, that one is supposed to add in to compensate for the low and mid-range responsiveness that big turbos give you. I know variable valve timing and lift gets the best of both worlds, but can someone enlighten me on what those worlds even are?? The point is moot anyways for the RB26....when you go high-lift and long-duration, what exactly do you gain, and what exactly do you have to give up?
 

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From what I remember from my days spannering, stock cams are a compromise between power and emissions. Aftermarket cams make the most of a particular set-up and its important to match the cam in terms of duration and lift with the turbo (in the RB case) and power band required. It used to be the case that older, pre electronic management days (yes, they did make cars with clockwork ignition :chuckle: ) used to have an issue with lumpy idle when using big lift cams. These days, the lumpy idle that would have usually been the case can now be tuned out with programmable ECU's such as F-CON and PFC.
So really, you're pretty much in a win-win situation with the RB. You get the increase in cylinder filling, perhaps a lower boost threshold and better top end performance. Again, you have a choice of lift/duration and even cam timing using adjustable cam pulleys in order to get the power band that you require for your application. E.g A cam for high RPM drag/circuit work would be a waste for a road car coz the cam would be designed to move the power higher up the RPM range.

I'm sure the tuners/experts can give a more enlightened explaination :bowdown1:

TT
 
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