i did a new radiator,cap,thermo i know the water pump is working i can let it sit and it wont over heat but when i go to drive it starts to overheat after 20 mins of driving. its smokes only when i get too vtec it smells a little sweet but i check the oil and it is not milky i did a compression test and it is 230-240 across the board.....but lastnight i put the new radiator in and it drove fine all night then overheats again today

 

also its a high compression b18c in da9

 

I don't know much about hondas, but I did blow a headgasket in my last subaru. Bubbles in the overflow tank? Water dripping out the exhaust? Are you losing coolant? All hoses good? There isn't any air trapped in the system is there?

 

if ur radiator is a used one try flushing it, chances are if u grabbed it from a wreckers it could have been sitting for a bit, if its new...double check all your hoses, im not sure, but i did notice when i replaced the rad in my 92 integra. it was fine for the first day but i noticed it would still over heat once in a while when in 3rd or 4th, after i flushed out the rad it stopped overheating... if u replaced rad cap and thermo, only thing i can think of is hoses or waterpump, possibly a leak somewhere causing u to lose coolant or not enough coolant getting ran through...other than that i dont got a clue good luck