Can you port/polish a 4stroke? and what exactly is it?

[roger86200x]

Can you have a 4-stroke motor ported and polished? And someone tell me what porting and polishing actually IS! lol

[NOS_350X]

you make everything completly smooth with nothing in the way so the flow of air into the cylinder isnt distracted equaling more air

[MR ATC]

well there is a little more to it then that. porting all depends on the type of power your trying to achieve. four stroke are more complicated to port then a two stroke and the only way to get a good job is to make sure the one porting it has a flow bench. porting involves reshaping the ports, possibly enlarging them, and redirecting them. the polish is the finish part that alows the airflow to move through the ports without turbulance. the littlest imperfection will disturb the airflow.

[roger86200x]

Thanks mr atc! I thought that that's all it was but I wasnt sure... so I turn to the experience of the forum members... I have knowledge/experience about the motor and rebuilding it and electrical stuff but upgrades and stuff like that are new to me....as well as the lower half of the motor :-D lol THANKS

[mkramm]

So what about just a polish? I got a dremel & some time? Would a polish give you anything, without a port?

[bbechtel16]

So what about just a polish? I got a dremel & some time? Would a polish give you anything, without a port?

I second the question.

[Dan Tenn]

yes, you can polish your ports yourself, and they even make magnetic templates that stick (assuming its not aluminum) to the ports as a guide if you want to do some porting. CAUTION: porting is not something an amateur with a dremel should attempt without lots of practice on grenaded motors. If you decide to polish it, be very very patient and use a steady hand. One OOPs and you can screw it up.

[TimSr]

Experts disagree upon whether polishing intake ports is helpful. While a smooth surface improves airflow, a rough surface aids in fuel vaporization.

Most amateurs are probably safe to polish up the exhaust port though.

Im speaking from a 2 stroke point of view, but I believe the same applies to 4 strokes in this case.

[250rmanfmf]

hea, TimSr is right somethimes good sometimes not. you want some turbulence, to help mix the fuel so it burns better. but you ca polish it if you have time.

Also on Mr ATC's post. if you port and polish a 4 stroke you need to go with bigger valves and in turn a bigger cam and springs. because you are increasing the volume of air/fuel mixure and if you still have stock small valves then your cycle will be not doing its job to the fullest.

[MR ATC]

Also on Mr ATC's post. if you port and polish a 4 stroke you need to go with bigger valves and in turn a bigger cam and springs. because you are increasing the volume of air/fuel mixure and if you still have stock small valves then your cycle will be not doing its job to the fullest.

that is not true. it all depends on the motor. some motors respond well with bigger valves and some do not.