how and what is the best way to tune up my irvine40 rc engine?

there two screws, one of wich i know is the mixture but the other im lost with cause as i play with it nothing changes realy, i seem to have a dead spot on reaching max that i just cant get rid of. thanks

the best way to tune a nitro motor is with an infrared temp gun.. set the carb back to factory settings.. start with your low speed needle first, its the one buy the throttle body, the small one.. then go to your high speed needle, the one on top. make sure you do small increments. 1/8 of a turn.. keep your eye out for a nice stream of blue smoke.. do not over adjust! give time for the carb to make changes. the dead spot means you've gone too far out.. factory setting are around.. high speed: 1 1/4 to 1 1/2 out from closed.. low speed: flush with the throttle body.. get the motor so that it idles smooth before you do any adjustments.. a temp gun is vitale.. it will let you know if you are over tuning and over heating the motor.. wich can quickly rune it($25 LOCAL HOBBY SHOP) a nitro engine runs at about 190- 220 degree's. if i had more details i could further help you.. boat, car, plane, gloplug… i did a search but couldnt find anything.. is it nitro, or 2stroke