how much usually does porting and polishing add?

[dirtbike77]

on a atc250r

bored.60 fmf, pipe,

[CHAINSAW]

a damn good port n polish.. will keep up, and beat most anything that is not on alcohol or PV'd. I have seen it with my own eyes...

[200x Basket]

it was hard to keep the front tire down in 5th :shock: i loved it 8) expect to spend about $500 for a good job. it takes time and skill. a really good shop will want your whole engine so they can measure how many degrees of blowdown, compression and other things that are determined by crank position.

[Lots_Of_Nothing]

on my 84 250R (i know its not a liquid, but just talking about porting) i got my cylinder, carb, and exaust manifold ported out to the balls, and when i got it back, and put together, i went to take off and almost killed myself, definatly wasnt used to that much power, i think porting is one of the most effective mods you can do............and i got it all done for 80 bucks :-P :-P ...lol....by my neigbor (owns a garage, and ports his racecars, and everybody elses, ....also all his sleds, hes a bigtime snowmobile freak)

[250rmanfmf]

porting and polishing a atv is like installing a chip in a truck or car. it is the best way to get the most hp from one mod. I really damn good port and polish will give you more power than most 250r bolt on upgrades together. Yea, you probably should have your carb bored too, they can usually get like 1.5mm more out of it.

[CHAINSAW]

a port is better then any mod you can add, and still have a safe reliable motor. Sure you can add nitrous, or a big 330 powervalve, but your gonna still be just as fast as the guy with a bone stock 250R and the best port n polish money can buy.

I know a good port guy in oklahoma if you want his info. He charges $150 or $200, cant remember, but his machines are top of the line when it comes to port jobs. He can also port to suit your needs.

[bbechtel16]

Does a good port and polish make as much of a differance on a 4 stroke as it does on the 2 stroker examples given?

[CHAINSAW]

I have little to no knowledge on 4 stroke motors and mods. I cant help you there, but I do know people do port n polish those also.

[250rmanfmf]

Yes, Port and polish on a 4-stroke is also a big power gain. but usaully when you port a 4 stroke, a lot of people switch to better cams, bigger valves and springs. I will have my 02 Raptor Ported and Polished once I get my racing cam and valves, springs.