I recently purchased an 03 evo 8. I havent had a turbo car in almost a decade. I was wandering if anyone might be able to help diagnose a couple issues i am having. First things First. I know I am losing boost slightly from the turbo compressor outlet gasket, this part is on order and will be here on wednesday. I am hoping that is causing the second problem but i am afraid it isn't. The second issue is missing and sputtering at shifts under heavy load and also it is 4000 rpm to 5500 rpm on a slow deceleration. when i run the rpms up and slowly bring my foot off or hold it in any one place for a bit in those rpm ranges it will start breaking up also. I just changed the plugs because i thought it might be them and went back with what was in it. it is a ngk iridium plug 3106. gapped to .23. problem remains does anyone have any ideas? Is this the right plug for me?
mods:
HKS tbe
turbo xs mbc
stainless manifold
all the hard pipes
no-cat
short intake
HKS 272 cams
Fmic after market but doesnt look like much more than stock
exedy light weight clutch and flywheel

 

get a tactrix cable and dump the ecu maps make sure they arent altered and also maybe try changing the plug gap a bit more.

 

it has been tuned by dyno4mance in gorgia. I am trying to get it in good working order so I can take it to mellon