XxMeltIcexX Posted November 16, 2008 Report Share Posted November 16, 2008 never posted mine, but heres a pic: After all the controversy over smooth/rough intake: Quote Link to comment Share on other sites More sharing options...
Wildcardracing Posted November 16, 2008 Report Share Posted November 16, 2008 Mine were slightly larger than 1/4", that was as big as I could go without adding material. Quote Link to comment Share on other sites More sharing options...
2001Stroker Posted November 16, 2008 Report Share Posted November 16, 2008 never posted mine, but heres a pic: Did you notice any difference after polishing them? You would think so. Kinda like porting and polishing a set of car heads. Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted November 17, 2008 Author Report Share Posted November 17, 2008 2001Stroker, you usually don't want any of the intake ports, or transfer ports polished. the fuel won't properly atomize and you will be down on power. its acutally more beneficial to have the ports bead blasted. that's smooth enough and then the fuel will atomize. the exhaust port is the one you want really smooth. you could just sand it with like 120-220 grit and that should be good enough. you can get it really smoooth, if you want. that would cut down on the chance for oil/carbon to stick. slobanshee, i have my cylinders bored .040" over w/a stage 3 race logic port job. the intakes were opened up big time (lowered/raised) and the exhaust port was widened/raised/reshaped. do you think it would be beneficial w/my type of port job? i wonder why the boost ports hurt your port work? i can't see how they should/could hurt ones top end. Quote Link to comment Share on other sites More sharing options...
2001Stroker Posted November 17, 2008 Report Share Posted November 17, 2008 2001Stroker, you usually don't want any of the intake ports, or transfer ports polished. the fuel won't properly atomize and you will be down on power. its acutally more beneficial to have the ports bead blasted. that's smooth enough and then the fuel will atomize. the exhaust port is the one you want really smooth. you could just sand it with like 120-220 grit and that should be good enough. you can get it really smoooth, if you want. that would cut down on the chance for oil/carbon to stick. I gotcha. Besides making sure an engine has a proper air/fuel mixture, isn't that the carburators other main function? To atomize the air/fuel? One would think that a smooth flow would make more power. Make it more efficient. Not tryin to be a smartass, just tryin to learn something. I got what you're saying about the exhaust, though. Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted November 17, 2008 Author Report Share Posted November 17, 2008 most people think that the polished intake ports, increase power, but they don't atomize the fuel properly. the carb doesn't atomize the fuel near enough. as the fuel/air mixture flows thru the ports, it catches all those little bumps (from bead blasting and are very, very, very small), the fuel gets atomized more. than the air/fuel mixture, gets inside the cylinder, and gets mixed in the turbulance created by the squish band, when the piston gets to top/dead center. the new air/fuel mixture also gets mixed w/old exhaust gas. the stuff that the cylinder didn't get expelled of. Quote Link to comment Share on other sites More sharing options...
Wildcardracing Posted November 17, 2008 Report Share Posted November 17, 2008 slobanshee, i have my cylinders bored .040" over w/a stage 3 race logic port job. the intakes were opened up big time (lowered/raised) and the exhaust port was widened/raised/reshaped. do you think it would be beneficial w/my type of port job? i wonder why the boost ports hurt your port work? i can't see how they should/could hurt ones top end. As I said a few posts ago, what works well with one builders work may not work as well with anothers. Try it for yourself. I didn't see a gain for what I was trying to achieve with those cylinders so I filled them in. They offered such minimal difference at the small size I cut them that I haven't bothered with them since. You will absolutely notice more gain/loss with correct/incorrect transfer port work. Quote Link to comment Share on other sites More sharing options...
firebanshee Posted November 17, 2008 Report Share Posted November 17, 2008 Cub cylinders come from the factory with auxilary boost ports and so do dirt bike motors and i think a tri Z comes with one on one side and you can add one to the other side so that should tell you alot. Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted November 18, 2008 Author Report Share Posted November 18, 2008 now that i think of it, my ski-doo rev snowmobile has them stock too. that's getting ported to, for this years snow season, along w/my 780 big bore yamaha sx viper. i finished porting my buddies viper 2 weeks ago, and that thing is becoming pretty killer. Quote Link to comment Share on other sites More sharing options...
505chevelle Posted November 18, 2008 Report Share Posted November 18, 2008 These required a little welding :thumbsup: Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted November 18, 2008 Author Report Share Posted November 18, 2008 wow...those are pretty big and it looks like you have them on top and bottom? Quote Link to comment Share on other sites More sharing options...
505chevelle Posted November 18, 2008 Report Share Posted November 18, 2008 wow...those are pretty big and it looks like you have them on top and bottom? Yes, top and bottom are both done. You should see the exhuast side. :thumbsup: Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted November 18, 2008 Author Report Share Posted November 18, 2008 wanna post pics of that? :thumbsup: i'm assuming that you have the auxillary exhaust ports added? Quote Link to comment Share on other sites More sharing options...
505chevelle Posted November 18, 2008 Report Share Posted November 18, 2008 wanna post pics of that? :thumbsup: i'm assuming that you have the auxillary exhaust ports added? Sorry don't have the exhaust pictures, but there are many ports over there, and required welding on that side also. This was all done before the Cub era. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted November 18, 2008 Report Share Posted November 18, 2008 most people think that the polished intake ports, increase power, but they don't atomize the fuel properly. the carb doesn't atomize the fuel near enough. as the fuel/air mixture flows thru the ports, it catches all those little bumps (from bead blasting and are very, very, very small), the fuel gets atomized more. than the air/fuel mixture, gets inside the cylinder, and gets mixed in the turbulance created by the squish band, when the piston gets to top/dead center. the new air/fuel mixture also gets mixed w/old exhaust gas. the stuff that the cylinder didn't get expelled of. Nice... Intakes tract should not be polished as said, it causes the gas to bead up instead of atomize for proper combustion... You can polish the exhaust...but, carbon tends to stick to it anyways.... A nice smooth intake and exhaust track is what you want, polishing might look cool for a pic, but it's not helping performance. The size/shape/timing of the ports is where the power is. Quote Link to comment Share on other sites More sharing options...
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