? Specific Time Area Spreadsheet for intial #'s work in progress. need ideas!

[one.man.band]

this is not based on jennings or bikes. based on standard engine design formulas used in textbooks. porting is based on power level. physical dimensions of ports will need to be traced and measured properly. degree wheel necessary.


features: (what i have done so far)
-english measure units based.
-unit converter from metric to english units.
-swept volume calculator
-bore/stroke ratio calculator
-BMEP based power level gains between 25% and up.
-specific time area intake, exhaust, blowdown ......all complete.
-RPM based. Pick your peak torque rpm.

features currently working on:
-transfer time area for lower power, small cc engines
-transfer time area for higher power larger cc engines
-physical port area measurement calculators for different sized ports. (in metric and decimal inch).
-degree varience (baseline before porting degree wheel measurement) in 2 degree increments up and down.
-total sum of angle + port size. (if degrees are to be kept constant ...will figure physical port dimensions) also (if port dimension is to be held constant, will calculate degree change needed). based of degree varience of +4, +2, 0, -2, -4 degrees. this will ease the pain in the ass of guessing.
-transfer/blowdown ratio calculator

future ideas:
-transfer/blowdown ratio calculator
-exhaust/blowdown ratio calculator
-big motor program refinement


========================
what features am i missing?
what else would be beneficial?
========================

-omb

 

[PogoInTheWoods]

Please let us know when there's a more refined redneck version available written on the back of a shovel with a lump o' coal so we may actually be able to fill in the blanks for ya.

opcorn:

 

[Scooterbum]

Well now that just give me a headache..........

 

[Gologit]

this is not based on jennings or bikes. based on standard engine design formulas used in textbooks. porting is based on power level. physical dimensions of ports will need to be traced and measured properly. degree wheel necessary.


features: (what i have done so far)
-english measure units based.
-unit converter from metric to english units.
-swept volume calculator
-bore/stroke ratio calculator
-BMEP based power level gains between 25% and up.
-specific time area intake, exhaust, blowdown ......all complete.
-RPM based. Pick your peak torque rpm.

features currently working on:
-transfer time area for lower power, small cc engines
-transfer time area for higher power larger cc engines
-physical port area measurement calculators for different sized ports. (in metric and decimal inch).
-degree varience (baseline before porting degree wheel measurement) in 2 degree increments up and down.
-total sum of angle + port size. (if degrees are to be kept constant ...will figure physical port dimensions) also (if port dimension is to be held constant, will calculate degree change needed). based of degree varience of +4, +2, 0, -2, -4 degrees. this will ease the pain in the ass of guessing.
-transfer/blowdown ratio calculator

future ideas:
-transfer/blowdown ratio calculator
-exhaust/blowdown ratio calculator
-big motor program refinement


========================
what features am i missing?
what else would be beneficial?
========================

-omb

You have a lot of free time, don't you.

 

[PogoInTheWoods]

Actually a pretty awesome/ambitious undertaking, omb. And what you seem to have pulled together so far is impressive if it translates into practical application implementation.

Nowthen...

What's in the pipe?:jester:

 

[one.man.band]

You have a lot of free time, don't you.

enough wood has been cut for the winter.

my youngest son loves motors on anything. teaching my youngest son about this kind of thing. telling him stories about the old dirt bike days 30 years ago, and blowing up the bike or mangling myself. scars do not teach much of anything. didn't know enough about them enough at that time to do anything but make them peaky unride-able pos's.

working out numbers is tiring. so i am making a spreadsheet.

caveman user friendly. plug in bore, stroke. trace and measure ports, degree ports. and it will do most all of the rest for basic work saws.

the rest of the stuff is not necessary, (but will be available for advanced users if they so choose).

i'd like to post it when it's complete, to contribute something to the site. but do not want to offend anyone by doing so. if that is the case i will keep it to myself.

-omb

 

[Gologit]

enough wood has been cut for the winter.

my youngest son loves motors on anything. teaching my youngest son about this kind of thing. telling him stories about the old dirt bike days 30 years ago, and blowing up the bike or mangling myself. scars do not teach much of anything. didn't know enough about them enough at that time to do anything but make them peaky unride-able pos's.

working out numbers is tiring. so i am making a spreadsheet.

caveman user friendly. plug in bore, stroke. trace and measure ports, degree ports. and it will do most all of the rest for basic work saws.

the rest of the stuff is not necessary, (but will be available for advanced users if they so choose).

i'd like to post it when it's complete, to contribute something to the site. but do not want to offend anyone by doing so. if that is the case i will keep it to myself.

-omb

I think it's great...especially the part about being "caveman user friendly". Go ahead on it and post it when you're done. You're putting honest effort and your own time into something that might be of use to the rest of the membership. If anybody is offended by it that's their problem.

 

[one.man.band]

I think it's great...especially the part about being "caveman user friendly". Go ahead on it and post it when you're done. You're putting honest effort and your own time into something that might be of use to the rest of the membership. If anybody is offended by it that's their problem.

thank you. appreciate that.

would hope that with some input from folks, it could get better refined. i will not post it until everything works as intended. these are not my formulas, just trying to make them available in an easy to use format.

-omb

 

[PogoInTheWoods]

I'm obviously peckin' at ya a little tongue in cheek, omb.

But as any one man band should know, some crowds are tougher than others.

That's why I learned how to juggle, too!

(Still workin' on the comedy, obviously.)

So go for it and keep those among us who are interested posted. You may be surprised at how it all evolves and where it goes.

 

[Dan_IN_MN]

Have you looked into Google Docs? It's web based so others can contribute.

 

[one.man.band]

I'm obviously peckin' at ya a tongue in cheek, omb.

But as any one man band should know, some crowds are tougher than others.

That's why I learned how to juggle, too!

(Still workin' on the comedy, obviously.)

So go for it and keep those among us who are interested posted. You may be surprised at how it all evolves and where it goes.

the fire extinguisher will be by my side when it's complete and post it i'm sure!

-omb

 

[one.man.band]

progress report: (that's if anyone is following this thread).

had to backtrack to correct a couple of calculations. fixed. amazing what a forgotten set of parenthesis will do.

i keep adding features, and it's making this a much more time consuming job.

added some things to make measuring easier:

program can now tell you where the piston crown is, and also where the bottom of piston skirt is anywhere in the stroke. also will let you measure in degrees, inches or mm's (or any combination), from either BDC or TDC positions (you choose).

currently working on calculator for pencil traced port areas, and a port area calulator to compare what you have, vs. what you need, and calculate what measurements you could use to get you there.

if you have done this before, you know how big of a deal this is.

-omb

 

[rmh3481]

I think your going to need to add in crankcase compression ratio's and squish velocity's if you want to tie it all together.

Sounds like a great project. I believe I still have some of Timberwolf's calculations that he put into spreadsheets, if your interested let me know.

 

[origionalrebel]

opcorn: dunno if i can understand it all but i'll know more when you're finished than i do now

 

[nmurph]

...caveman user friendly. plug in bore, stroke. trace and measure ports, degree ports. and it will do most all of the rest for basic work saws...

I can see a Geico commercial here-

picture a camera zooming in over a guys back seated at some sort of work bench in a poorly lit garage. You can see a cylinder in one hand and a Dremel in the other, and a voice-over saying "Geico, so easy even a caveman saw builder can do it."



Maybe we could have a casting call for the builder. Nominations?????



All Geico Cavemen Commercial - YouTube


Love the thread ida OMB!!

 

[half_full]

great idea. Are you using xls 2010 version?
When I read through all the porting threads I could find I copy/paste the important details (weeds out some of you pecker heads bickering :msp_tongue: ) into a word doc. I save the user name that posted it so I know who to thank. It turned 100's of pages of reading into 12 pages of what I thought was needed to get a start. Trouble is I would still need to do the calculations.
Your efforts would be most welcome.

 

[jammin_with_j]

great thread, I've not done porting but very interested in it. a caveman spreadsheet sounds fantastic, a good place to start atleast. good luck, I will be interested to see your finished product

 

[jerrycmorrow]

hey omb, being a compulsive spreadsheet writter (i figure if you're going to the trouble to calculate something by hand you'll prolly need to do it again sometime so why not develop a spreadsheet) i'm eagerly awaiting your final product.
i developed one to convert inches before tdc to degrees also. just cause its hard to measure the vertical offset on some cylinders

 

[watsonr]

hey omb, being a compulsive spreadsheet writter (i figure if you're going to the trouble to calculate something by hand you'll prolly need to do it again sometime so why not develop a spreadsheet) i'm eagerly awaiting your final product.
i developed one to convert inches before tdc to degrees also. just cause its hard to measure the vertical offset on some cylinders

And in that converter, do you have a bunch of different cylinders measured?

 

[jerrycmorrow]

And in that converter, do you have a bunch of different cylinders measured?

Just the one I was working on. IIRC you just need to know the stroke and input the specified vertical offset. You want it ill send it. Of course all the standard disclaimers apply. I did run through several hand calcs to proof it