mopar1rules

my cylinders are ported, so on my gauge i'm around 135-138 lbs of cranking compression. running compression will be higher.

i cut .030" off my head, and i have .050" squish. i have pro-x pistons and moose gaskets all around.

READ MY LAST SENTENCE IN MY PREVIOUS POST ABOUT 27.2MM. YES, IT SHOULD TAPER NICELY FROM PORT WINDOW TO EXHAUST FLANGE. what measurements from cylinder deck, to exhaust port roof do you measure at now?

i said that's w/OEM base gaskets and cometic gaskets. don't remember the OEM and cometic thicknesses, but whatever gaskets are the same thickness as cometic and OEM, will give you the same 195* duration w/27.2mm from cylinder deck.

i mean you can't jet down, meaning go down in jet sizes, which would lean out the motor, as you increase airflow, either by pods, or by airbox lid removal, or by porting, etc. anytime you give the engine more air, you need to give it more fuel as to keep the proper air/fuel mixture. also, you aren't going to hurt anything by increasing your main jet size. i'm surprised you don't need a 310 main or so.

first off, how the heck is your motor still running, w/only a 190 main? second, you can't get down as you increase airflow.

the very top of the piston crown, will protrude above the cylinder deck. the very edge of the piston crown won't. also 195* exhaust is 27.2mm, using cometic and OEM base gaskets and head gaskets.

i'd like to see some pics of the exhaust port (cylinder side) and pics of the transfers and boost. that intake looks like nothing special. they appear to have only have been "knife edged" a little and the boost port entrance looks to have been touched up some. big deal. hope you didn't pay much for that "port job".

don't blame pilot plugging issues on the stock carbs. you have a bunch of crap in your tank and lines. any carb will get its pilots plugged up, if there's crap in the fuel system.

yeah, you're thinking of the 6.5:1 like a car's comp ratio. the 6.5:1 is the corrected or trapped compression ratio like blowit stated, which is the cylinder volume from the roof of the exhaust port and everything above divided by the volume above the piston when its @ TDC.

i would think that the hi-revs would be good for 8800-9000. this is the place where i found the dyno sheet to the paul turner hi-revs. check out the dyno sheet here. not saying its right, but just where i found my previous info. sorry if what i had posted was wrong. http://www.angelfire.com/extreme2/yambanshee/techtips/pipes/pipeinfo.html

i would leave it alone for now. specs seem fine to me. maybe could of had a little longer blow down time tho. on the dyno sheet i've seen of the pt hi-revs on stock porting, they peaked @ 7500. your current exhaust is good for like 9000. try out your current porting and then decide from there what else you want to do.

sloryder, i tried to reply to your message, but i can't/don't know how to access my inbox on here. i hate this new inbox/message setup. anyway, bassed off of what you said about your port changes and assuming a .017" deck height, your new port specs are: exh 187.6*(1.5mm raised)- 189.6*(2mm raised) tr 125.2* boost 111* blow down 31.2*(1.5mm raised)- 32.2*(2mm raised)

the reeds that get the metal strips are the boyesens. if you run like carbon techs or stock reeds, then you need to keep the stoppers on there, or else the petals will break off. if you want to help out flow, then notch the upper reed stopper, so it doesn't block off flow to the boost port.

no one can give you any specs/durations etc, until we know your pipe, and riding style. also, if someone says that they have an exhaust of 188* and main transfers of 124*, that would mean the exhaust port is open for 188* of crank rotation and the main transfer ports open for 124* of crank rotation, and that the blow down timing (which is very important) would be 188*-124*=64*/2=32* blow down.

amsoil dominator here @ 50:1 for 3 yrs w/o a problem.

this might help.... http://www.atvsource.com/articles/product_reviews/2001/050901_vitos_superstock_pistons.htm

here dusty_v141, read this till your hearts content..... http://edj.net/2stroke/jennings/

my buddy had the same thing happening on his '90 shee. it turned out to be the coil. let him try your coil and see if the problem goes away.

you don't adjust the air screw by the # of turns you thread it in from when it starts to thread in.....you thread the screws in all the way until seated and then count the # of turns that you start to uncrew/open up the air passage. set your air screws to 1-1/2 to 2 turns out from seated. glad to hear you got it up and going.

did you play w/the air screw? did you put the black rubber cross over tube back in between the carbs? do you accidently have the throttle cable tensioned some? did you mess w/the idle speed screw on the tors top? did the carb stop leaking fuel at least....LOL.

your seat might have some crap in there, causing the needle to not seat and shut the fuel off. the needle could just be shot too, and/or the float is mis-adjusted. check the needle and seat and float height.

this one can kinda be helpful... http://www.angelfire.com/extreme2/yambanshee/techtips/pipes/pipeinfo.html

if i recall correctly, the t5's on stock porting, will pull up to like 9000. there is a dyno sheet floating around on here somewhere. i'm going to try and find it and then post the link. here is the link to a topic, where i asked pretty much the same question. about 1/2way down the page, there would have been a pic posted by snope, of a pipe dyno comparrison, that for some reason isn't showing up anymore. also, there is a link posted, like another post down, w/a link to some dyno sheets. for some reason that link isn't working either. don't know why. http://bansheehq.com/forums/index.php?showtopic=112482&view=&hl=dyno%20sheet&fromsearch=1

leave needles stock. air screws at 1-1/2 turns out. 27.5 to 30 pilots and 320 to 330 mains.