nitro stan

hey all my name is stan i got a nitro RS4 version 2 and a eletric rustler. i would like to know how big of a engine i can put in the rs4 it has a nitrostar .15 now it runs good but i would like to go faster when i get the hang of driving this car. also whats the secret to getting the throttle linkage to idle and pull WOT with out have to max out the trim? its like the servo wont pull enough to get WOT i have to max the trim out to get it then my beakes wont work good till i turn the trim all the way back down. iv set the rod to 23mm like the HPI book says and centered the servo still cant get it right. its a futaba s3003 servo heres a link to some pics


this is full throttle


thanks stan

hpi apollo

you can get an os 18 cv-rx, good cheap engine, runs strong, reliable, easy to tune, also for the throttle linkage, i beleive if you search a fwew pages in the ntiro on road section miamizfinest has a post of how to tune a nitro engine and im pretty sure it has linkage tips too