Hey guys... I have been looking at the Evo 4 engine... Looks good. Only problem is, I have never had a Sirio and dont know how to set them up. Has anyone tried the Evo 4??? Does it require the Sirio pipe set or can it perform with other pipes like the Skyline VR12 plus??? Sirio plugs a must or can picco based plugs work on the engine? I check all of these before going and buying a new engine. Im feeling the urge to buy a new engine and Im thinking of getting a JL red dot or an Evo 4. Im in no urge to buy this, I just got a relatively new OS TZ and have changed the piston/sleeve for a new one and should hold atleast until summer.