What is the estimated power and torque hike if the following is carried out to the 4G63 engine. Port and polish on the cylinder head plus engine blue printing and balancing? Anyone has the done it out there with figures, please share.

Also, what air filters go has the biggest power hike towards the Evo. A'PEXi filter or the HKS SPF or even Blitz? Would having an aluminium air filter pipe make any diff over the OEM plastic piping?

Thanks for the feedback! Cheers and Merry Christmas!


www.SpeedXS.com - Center for Japanese Performance Cars

 

jackson racing has a head for our car all maxed out.not sure on all the specifics but its the second time i seen them advertising in one of the sport compact magazines,also,i believe its aebs does specialized work on all kinds of head with some excellent results.they worked on some wrx heads for a build up for 1000 h.p 2.0 and got some sick airflow out of em .