srcarr52
We can't stop here, this is bat country.
Is that the one I gave you? You also need to know the rod length.
? Specific Time Area Spreadsheet for intial #'s work in progress. need ideas!
- Thread starter one.man.band
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Is that the one I gave you? You also need to know the rod length.
Sprintcar
Chainsaw Slut
Looks like a spread sheet for a sprint car motor, sort of.
no. that's the one i gave you - entitled "public-piston vertical to crank angular conversion.xls" - when you sent me the one entitled "Husqvarana394mod.xls". btw shaun i discovered and modified some incorrect definitions and an incorrect statement in the formulas extrapolation; this had no effect on the final result though
BTW you need to know the specified vertical distance of top of piston from TDC, the stroke, and the rod length
watsonr
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Unless I'm cutting squish ban and/or the combustion chamber it really doesn't do me much good for a plain Jane woods port. Sort of like buying a degree wheel... I don't think it matters.
What would really make a hill of beans is something to cut the base to get better squish without a lathe!
What would really make a hill of beans is something to cut the base to get better squish without a lathe!
half_full
ArboristSite Guru
That would be one hell of a spreadsheet formula.
one.man.band
ArboristSite Guru
older 2007. graphics are kept to a minimum. may include some graphs, but still deciding on that. should work fine with 2010.
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one.man.band
ArboristSite Guru
yes sir. thought measuring from piston top side and bottom of skirt converter would help as well.
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one.man.band
ArboristSite Guru
no cylinders were measured.
what i was referring to was measuring port open and fully open points in either degrees, mm or inches. example: if you could not get a clear reading with a wheel, you could measure a length in mm or inches inside the cylinder, from a known point, and then convert back into degrees if necessary from that length.
reading your question again...are you referring to deck height? i could add that feature. simple calc. but if you need something different than that, i need more clarity on what you want to do.
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one.man.band
ArboristSite Guru
do a search on the internet on surface plates.
using glass and valve grind compound i managed to do a couple of lipped iron cylinders with lots of patience. may work for you.
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one.man.band
ArboristSite Guru
rmh....
early on with the program, i wanted to add squish velocity, compression and timing changes. rather than get into a debate on these, what i will say is that i did not include a combustion model into this spreadsheet for various reasons.
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one.man.band
ArboristSite Guru
version #1 will be out in about one or two weeks. (april).
trying to hurry to get this done before my job starts going full bore for the season.
only two things left to do are a crank length calculator and a port dimension calc for grinding.
also some simple instructions.
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blowdown... pita. the simplest thing to do with degree wheel, turned into a mathematical nightmare for time-area. had to go back to fix multiple calculations. this is interesting (to me anyway), in that this will be one of the few programs in existence (that i am aware of anyway, that will include it for actual time-area). no textbooks list how to do this calc, only the final answer.
boost ports: someone pm'd me about those. so far, i have treated all transfer ports the same. i will separate boost port calcs, so you can see how they contribute to overall transfer time-areas. these will be based on actual boost port size. i have no way to calculate piston windows and relate them to time-areas, sorry. if anyone knows how to bring piston windows into calcs, (or if this can even be done, pm me.)
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trying to hurry to get this done before my job starts going full bore for the season.
only two things left to do are a crank length calculator and a port dimension calc for grinding.
also some simple instructions.
----------------------------------------------
blowdown... pita. the simplest thing to do with degree wheel, turned into a mathematical nightmare for time-area. had to go back to fix multiple calculations. this is interesting (to me anyway), in that this will be one of the few programs in existence (that i am aware of anyway, that will include it for actual time-area). no textbooks list how to do this calc, only the final answer.
boost ports: someone pm'd me about those. so far, i have treated all transfer ports the same. i will separate boost port calcs, so you can see how they contribute to overall transfer time-areas. these will be based on actual boost port size. i have no way to calculate piston windows and relate them to time-areas, sorry. if anyone knows how to bring piston windows into calcs, (or if this can even be done, pm me.)
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one.man.band
ArboristSite Guru
spreadsheet won't be posted.
some beers and some thinking led me to believe that it's not a good idea to do so. with no complaints from anyone. just myself. lot of my time went into it, and it still will be done shortly.
sorry to disappoint. no disrespect intended.
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some beers and some thinking led me to believe that it's not a good idea to do so. with no complaints from anyone. just myself. lot of my time went into it, and it still will be done shortly.
sorry to disappoint. no disrespect intended.
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Mastermind
Work Saw Specialist
I wanna see it.
I did 185 woods ports last year.......that taught me a lot.......but I have much to learn. :msp_wink:
I did 185 woods ports last year.......that taught me a lot.......but I have much to learn. :msp_wink:
one.man.band
ArboristSite Guru
this is the deal. numbers are just numbers until they are proven. my concentration was on the porting aspect only. i don't own a true simulation program for 2 strokes to compare it too. i don't have access to a dyno for these tiny motors. until then it remains unproven.
will offer the sheet up to someone when its complete. if its accepted, he can do whatever with it. post it, not post it, publicly call it garbage, or keep it under his hat to use. if hes willing to share it and gives me the go ahead to post it, then i will do so. but its not up to me anymore.
i'm confident in its use as a tool. or wouldnt have spent at least 80 hrs on it so far of my time. willing to put my money where my mouth is. will add $100 towards the cost to have a someones saw thats already on the repair bench tweaked using only the sheet numbers. the $100 will remain with the wrench spinner for his time. i won't pick the saw. or for that matter want to own the saw when its complete.
this was/is only a tool to obtain relative power goals and calculate time-areas easily. believe me when i say its not easy to calculate these numbers, and then massage them into something that most folks can use.
i don't fool or race 2 strokes anymore. if i did, i would have never began this thread in the first place. similar to what someone has said in a different thread, never been on a board where so much information is shared. and thats why i think its a great forum, even though i dont fool with these motors.
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will offer the sheet up to someone when its complete. if its accepted, he can do whatever with it. post it, not post it, publicly call it garbage, or keep it under his hat to use. if hes willing to share it and gives me the go ahead to post it, then i will do so. but its not up to me anymore.
i'm confident in its use as a tool. or wouldnt have spent at least 80 hrs on it so far of my time. willing to put my money where my mouth is. will add $100 towards the cost to have a someones saw thats already on the repair bench tweaked using only the sheet numbers. the $100 will remain with the wrench spinner for his time. i won't pick the saw. or for that matter want to own the saw when its complete.
this was/is only a tool to obtain relative power goals and calculate time-areas easily. believe me when i say its not easy to calculate these numbers, and then massage them into something that most folks can use.
i don't fool or race 2 strokes anymore. if i did, i would have never began this thread in the first place. similar to what someone has said in a different thread, never been on a board where so much information is shared. and thats why i think its a great forum, even though i dont fool with these motors.
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steve316
ArboristSite Operative
onemanband
I still drag race at 63; I needed a new saw 2yr ago, bought a Dolmar 6400. Cad took over and I have 8 saw now. My point is you don't have to work on them to be interested in saw modification. I am interested in this post as it offers a new perspective. Thanks for offering your thought.Steve
I still drag race at 63; I needed a new saw 2yr ago, bought a Dolmar 6400. Cad took over and I have 8 saw now. My point is you don't have to work on them to be interested in saw modification. I am interested in this post as it offers a new perspective. Thanks for offering your thought.Steve
pops21
Addicted to ArboristSite
One man band the next puff is on me my friend. You are one smart dude. I think some folks are just jelous. You might not post much on arborist site, but what you do post is top notch college professor well thought out stuff. Kudos to you. I look foward to being able to possibly use your program. YOU DA MAN.
One man band the next puff is on me my friend. You are one smart dude. I think some folks are just jelous. You might not post much on arborist site, but what you do post is top notch college professor well thought out stuff. Kudos to you. I look foward to being able to possibly use your program. YOU DA MAN.
Just to clarify some points. Some college professors, ie poly sci, philosophy, history, etc can and do espose their own agenda. Those professors in the hard sciences, physics, engineering, etc would have a much more difficult time with their own agena and tend to stick with what can be proven and demonstrated (scientific method).
one.man.band
ArboristSite Guru
steve316 - racing at 63 is awesome! hoping i can get up just to pee if get there. thanks for some inspiration.
sachmo - like your perspective. i'm a doubter until i see something actually work, as well. all i can say is this. take something like durations. they have been around something like 30 years, i don't know for sure. they have been used for that long because they work. no question. that's why so many still use it today. now take time-areas, they have been around for 25+ years. i'm guessing that they work. but folks have been using them, nonetheless. now take time-areas related to bmep which has been around since about '95, does it work? i've seen the results published that use a saw motor as an example. from what i saw, its valid. have i tried any of this on a saw? the answer is no. lots of software is based on this. since that time folks have tweaked this further. i have done no tweaking. the only way to get time-areas is with calculations, a spreadsheet just lets you do these repetitive calculations easier.
maybe some folks don't understand why i have a reservation with the spreadsheet being released. something called respect. what many don't realize, working on your own motor is one thing, but working on someone else's is another. most will never be in those shoes. when you work on someone else's, you are judged only by your last build. when you wake up in the middle of the night because you can't remember if you torqued a bolt or not. then it finally hits you. i give these folks respect, and for that matter, anyone else who works on motors for a living, because they have earned it.
this thing is only a tool. it has not been through the paces. i still have some doubts. but no agenda. no agenda pro or con for anyone else either. if it doesn't work, nothing lost, nothing gained. if its not evaluated be someone who knows his ####, what good is it anyway, for anyone else??
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sachmo - like your perspective. i'm a doubter until i see something actually work, as well. all i can say is this. take something like durations. they have been around something like 30 years, i don't know for sure. they have been used for that long because they work. no question. that's why so many still use it today. now take time-areas, they have been around for 25+ years. i'm guessing that they work. but folks have been using them, nonetheless. now take time-areas related to bmep which has been around since about '95, does it work? i've seen the results published that use a saw motor as an example. from what i saw, its valid. have i tried any of this on a saw? the answer is no. lots of software is based on this. since that time folks have tweaked this further. i have done no tweaking. the only way to get time-areas is with calculations, a spreadsheet just lets you do these repetitive calculations easier.
maybe some folks don't understand why i have a reservation with the spreadsheet being released. something called respect. what many don't realize, working on your own motor is one thing, but working on someone else's is another. most will never be in those shoes. when you work on someone else's, you are judged only by your last build. when you wake up in the middle of the night because you can't remember if you torqued a bolt or not. then it finally hits you. i give these folks respect, and for that matter, anyone else who works on motors for a living, because they have earned it.
this thing is only a tool. it has not been through the paces. i still have some doubts. but no agenda. no agenda pro or con for anyone else either. if it doesn't work, nothing lost, nothing gained. if its not evaluated be someone who knows his ####, what good is it anyway, for anyone else??
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