RadarRacing Posted June 8, 2009 Report Share Posted June 8, 2009 Wow odaen havent seen you in a long time that mapper was very helpful a few years ago when I did 50 and 90cc motors with odd cylinders and rod lengths. I even used it to figure rod lengths a few times based off port durations adn heigths. Stock port timing on a banshee is about 185/115. You dont get port timing strictly off the top of the cyl. It is actually the top of the leading edge of the piston. Honestly if you wanna not hack up your cylinders but wanna play with the motor get a .060 base gasket and get the head decked or some tighter squish domes to get the squish around .040 that way you can get another head and go back if needed. If you want to know what pipes make hp at a particular range or how to port for a pipe you need a lot more info. To tune porting for a pipe theres a formula.. port duration X 1700 divided by the tuned length of the pipe will get you a rpm range where you'll make power. Honestly I like to do things myself but I'd pay $300$500 to get a proven combo and it will run like it should. Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted June 8, 2009 Report Share Posted June 8, 2009 Stock port timing on a banshee is about 185/115. You dont get port timing strictly off the top of the cyl. It is actually the top of the leading edge of the piston. Honestly if you wanna not hack up your cylinders but wanna play with the motor get a .060 base gasket and get the head decked or some tighter squish domes to get the squish around .040 that way you can get another head and go back if needed. the specs/measurements i provided, are based off of TDC. i gave him the measurements from the cylinder deck, so it would be easy to set a calipers and scribe the measurement, and then have the duration he's looking for. Quote Link to comment Share on other sites More sharing options...
deckheight Posted June 9, 2009 Report Share Posted June 9, 2009 Not really, given the info provided you pretty well covered it near as I can tell... thanks deckheight!! :thumbsup: yeah, i've been pretty busy playing w/the software here. i love the stuff. i still didn't get the chance to run my buddies shee, as we are waiting on a new throttle cable. during reassembly, i noticed that the throttle slides didn't want to return correctly to idle position, when i was syncing the carbs. tracked it down to a piss poor throttle cable. good thing i didn't try to take it out for a spin.....LOL. i'll keep in touch w/you. hey deckheight, do you have any info to help this fellow out? you gotta have some valuable input, as you always do....LOL. take care. Quote Link to comment Share on other sites More sharing options...
SLORYDER Posted June 10, 2009 Author Report Share Posted June 10, 2009 Hmm you say you raise the transfers to smooth the powerband after raising your exhaust...I was looking at the layout and isn't the boost port at the same duration as the transfers...I can get in there and raise the boost port without any special tools.. So it should have some effect on blowdown and what not if I raised it a bit right... Quote Link to comment Share on other sites More sharing options...
blowit Posted June 10, 2009 Report Share Posted June 10, 2009 Hmm you say you raise the transfers to smooth the powerband after raising your exhaust...I was looking at the layout and isn't the boost port at the same duration as the transfers...I can get in there and raise the boost port without any special tools.. So it should have some effect on blowdown and what not if I raised it a bit right... Timing between the boost and xfers needs a pretty close relationship. Raising the boost without the xfers will give you some problems. In some circumstances, it is easiest to put a plate under the cylinders and/or mod the timing edge of the pistons and correct things at the head rather than porting. This is the "poor boy" port job but it will help rather than doing nothing. B Quote Link to comment Share on other sites More sharing options...
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