mopar1rules Posted June 6, 2009 Report Share Posted June 6, 2009 Stock is 176-178* open on exhaust. Brandon what are you using as a deck height and for base gaskets? i keep coming up w/179.967* for .127mm (.005") deck height and 181.258* for .4318mm (.017") deck height. the .017" deck height is what i seen personally, using cometic/wiseco base gaskets. i don't see how your getting 176*-178* stock duration. can you tell me what i'm doing wrong? Quote Link to comment Share on other sites More sharing options...
blowit Posted June 6, 2009 Report Share Posted June 6, 2009 (edited) what are you using as a deck height and for base gaskets? i keep coming up w/179.967* for .127mm (.005") deck height and 181.258* for .4318mm (.017") deck height. the .017" deck height is what i seen personally, using cometic/wiseco base gaskets. i don't see how your getting 176*-178* stock duration. can you tell me what i'm doing wrong? Probably just what is input for oem port height. Banshees are supposed to be a zero deck height motor. Never are but that is theoretical. Edited June 6, 2009 by blowit Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted June 6, 2009 Report Share Posted June 6, 2009 what were your findings for OEM port heights? i come up w/30.5mm (from deck to roof) for the exhaust. is that what you got? Quote Link to comment Share on other sites More sharing options...
blowit Posted June 6, 2009 Report Share Posted June 6, 2009 what were your findings for OEM port heights? i come up w/30.5mm (from deck to roof) for the exhaust. is that what you got? I just have my recorded figures in front of me but I am sure you are on the right track. :thumbsup: B Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted June 6, 2009 Report Share Posted June 6, 2009 ok, cool. :thumbsup: Quote Link to comment Share on other sites More sharing options...
SLORYDER Posted June 6, 2009 Author Report Share Posted June 6, 2009 So would 190 on the exhaust be pushing it without touching the transfers? Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted June 7, 2009 Report Share Posted June 7, 2009 IMO yes. what are you planning on doing w/this thing, to want to have 190* of duration on the exhaust? Quote Link to comment Share on other sites More sharing options...
SLORYDER Posted June 7, 2009 Author Report Share Posted June 7, 2009 (edited) well, I will have pt hi revs and 34 mm carbs, so I am just trying to get her to rev to the moon for full blast beach rides and be abli to spank on some 4 pokes if need be Would like to refrain from destroying my midrange though Edited June 7, 2009 by SLORYDER Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted June 7, 2009 Report Share Posted June 7, 2009 i'm not sure what the pt hi-rev pipes like for durations etc, but i feel that you should be widening your exhaust port first, to get the time/are needed, before raising. that way you'll help the upper mid-range and top (which is what you want), but still hold the current bottom end. if you raise the exhaust (measurement from cylinder deck to port roof will than be 28mm) to have 190.15* of duration, w/o doing any widening, then you will kill the bottom end and have such a long blow down timing....39.22* to be exact. if you want to raise the exhaust that much, which IMO i don't think you need to (IMO 188* should probably suffice), you should IMO raise your transfers too, to help shorten the blow down timing and help hold a decent power delivery, in the bottom and midrange. IMO, I don't think you'll want a blow down time of more than 36*. also, remember that port roof arcs will also dictate the way the power comes on. large radius' which = flatter roofs, will equal a strong pulse and hard hit, versus a smaller arc/radius, which will = a more arced roof will give you a smoother power delivery. maybe someone else can input something? maybe someone else has some port timing specs for your pipes that they would like to share? Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted June 7, 2009 Report Share Posted June 7, 2009 disregard my previous blow down specs, timing specs, and measurement specs. i punched in the wrong data into the software....LOL. $hit in just gives $hit out. here are my corrections..... i would personally use 186*-188* of duration....if using OEM base gaskets, you should have around .017" of deck height, so measurement from exhaust port roof to cylinder deck would be 29.38mm (186* duration) and 28.9mm (188* duration). blow down timing would be 34.56* for 188* exhaust and 35.57* for 188* exhaust. if i was in your place, i would keep the blow down timing around 34* for your beach/dune riding. so, raising of the transfers would be required some. if you are still stuck on having 190* duration, your measurement from cylinder deck to port roof would be....28.4mm=190.07* of duration. hope this helps. Quote Link to comment Share on other sites More sharing options...
deckheight Posted June 7, 2009 Report Share Posted June 7, 2009 Sounds like somebody has been busy :biggrin: :biggrin: Way to go man... disregard my previous blow down specs, timing specs, and measurement specs. i punched in the wrong data into the software....LOL. $hit in just gives $hit out. here are my corrections..... i would personally use 186*-188* of duration....if using OEM base gaskets, you should have around .017" of deck height, so measurement from exhaust port roof to cylinder deck would be 29.38mm (186* duration) and 28.9mm (188* duration). blow down timing would be 34.56* for 188* exhaust and 35.57* for 188* exhaust. if i was in your place, i would keep the blow down timing around 34* for your beach/dune riding. so, raising of the transfers would be required some. if you are still stuck on having 190* duration, your measurement from cylinder deck to port roof would be....28.4mm=190.07* of duration. hope this helps. Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted June 7, 2009 Report Share Posted June 7, 2009 (edited) 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. Edited June 7, 2009 by mopar1rules Quote Link to comment Share on other sites More sharing options...
SLORYDER Posted June 8, 2009 Author Report Share Posted June 8, 2009 disregard my previous blow down specs, timing specs, and measurement specs. i punched in the wrong data into the software....LOL. $hit in just gives $hit out. here are my corrections..... i would personally use 186*-188* of duration....if using OEM base gaskets, you should have around .017" of deck height, so measurement from exhaust port roof to cylinder deck would be 29.38mm (186* duration) and 28.9mm (188* duration). blow down timing would be 34.56* for 188* exhaust and 35.57* for 188* exhaust. if i was in your place, i would keep the blow down timing around 34* for your beach/dune riding. so, raising of the transfers would be required some. if you are still stuck on having 190* duration, your measurement from cylinder deck to port roof would be....28.4mm=190.07* of duration. hope this helps. Thanks, just what I was looking for. Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted June 8, 2009 Report Share Posted June 8, 2009 (edited) Thanks, just what I was looking for. no problem. glad i could help. :thumbsup: Edited June 8, 2009 by mopar1rules Quote Link to comment Share on other sites More sharing options...
SLORYDER Posted June 8, 2009 Author Report Share Posted June 8, 2009 maybe someone else can input something? maybe someone else has some port timing specs for your pipes that they would like to share? This Quote Link to comment Share on other sites More sharing options...
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