1_fast_gto

iTrader: (1)

i have a set of heads im going to have ported and polished, but the other day someone was telling me that polishing a daily driven cars heads wasnt really a good idea, they said that the fuel wasnt atomizing properly at idle and would cause the fuel to puddle and cause drivability issues if your not at WOT due to the polishing, i thought it sounded like something with a tune, like the injectors were being held open too long at idle. but i wasnt real sure, i was just wondering if anyone has heard of this and what their take is on it, thanks

Paint_It_Black

iTrader: (1)

You don't want a mirror finish on the intake runners. When I port a set of heads I finish with a 120 grit cartridge roll on the intake. I do polish combustion chambers and exhaust runners though. Until the fuel is burned you want to keep it suspended. Google "boundary layer" pertaining to intake runners.

ssinister550

iTrader: (8)

polishing really does nothing either way. on exh. ports and comb. chambers it makes them easier to clean if the motor is being freshened frequently (race motor) and on street motors it delays the process of carbon buildup in those areas a little bit. Typically intake runners like a rougher finish though especially around the short turn area because for some reason with a rougher short turn finish, the air is less prone to separation, air tends to hang on to a rougher finish more so than a polished, smoother finish. I usually finish my ports with an 80 grit cartridge roll or a flapper mandrel with a piece of 100 grit if the customer wants them to look pretty. hope that helps.

1_fast_gto

iTrader: (1)

thanks guys, alot of help here.