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


MLS stands for multi layered steel in case you didn't know.  Like a good high end racing gasket, the stock Toyota part has a sealing ring around the bores to add more clamping pressure where it's needed.
The block is machined by Ed Pink to accept 1/2″ ARP studs, replacing the 11mm stock bolts.  The block and head are first drilled then reamed for close tolerances so the parts won't walk.
The factory dowel pins are bored out to 1/2″ as well.  The studs are torqued to 125 ft/lbs, a lot to hold the 30 psi of boost.  Ed Pink align hones the main bores after studding to get rid of any crank bore distortion the highly torqued studs might have caused.
The stock Toyota block is a high pressure die cast piece that is both light and strong.  The more we learn about the 2AR, the more impressed we are by it.  The bores are very round and concentric right from the factory and no additional work needs to be done to them.
The entire block only weighs 51.75 lbs but can easily and reliably contain 800 plus hp!  The assembled long block only weighs about 180 lbs and the fully dressed engine weighs a feathery 220 lbs!  This is nearly half the weight of a lightweight Chevy LS V8 engine and old school Japanese 4 cylinder engines.  The light weight enables the team to have a rearward weight bias.  The power density of this engine is amazing.  More teams should consider 2AR swaps!
The 2AR has an asymmetrically located crank.  This reduces piston slap and allows for more dwell time at TDC.  On a stock car this is done to reduce NVH on the long stroke engine but it also helps to reduce side loads in this racing engine and is partially responsible for the long piston and component life.  Longer dwell time at around TDC also improves volumetric efficiency and combustion efficiency.

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