Nerd’s Eye View: Inside Fredric Aasbo/Papadakis Racing’s Amazing V8 eating 2AR Toyota Engine

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The stock 2AR head has huge intake ports so with the exception of the bowl and the entrance to the bowl, they remain stock.
 
The water passages for the heater are welded shut.
 
The cams are retained in this cast housing which gets rid of the alignment issues associated with cam caps and stiffens the head.  The 2AR has some neat engineering in it.
 
The cams are ground by SLR.  Notice that they have the proper asymmetrical profile with an inverted opening flank required by roller cams.  This means a small grinding wheel had to be employed in the grinding process.  A lot of aftermarket cam makers ignore this sort of stuff but it makes a huge difference in how well the cam works.
 
The variable cam timing on the exhaust side has been disabled.  Although this sacrifices a decent amount of torque, it was found that the variable cam drive could not keep up with the engine's transient response and contact with the exhaust valve would result.
 
With a 1.7:1 ratio rocker, the cams have 0.418″ of lift at the valve with a relatively short 282 degrees of duration  This sort of spec should result in a very wide powerband.

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