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HCMP
Posted: Mon Mar 31, 2008 8:43 pm
by pat123
HCMP
hybrid and combustion metering for propane
I know it is basic but I had problems with this and it should help people with hybrid fueling.
tell me if you like it
edit: now has propane, butane, and mapp
Posted: Mon Mar 31, 2008 8:46 pm
by Counterstriker
Picture not working for me.
Posted: Mon Mar 31, 2008 8:47 pm
by bigbob12345
this is really well done and completely accurate
I like it a lot, will give me a break from that calculator for a while
counterstriker:it is a fuel and meter calculator, just pres the download button

Posted: Mon Mar 31, 2008 8:55 pm
by pat123
Thanks it only took about 5 minutes to make. I am going to add some more stuff to it soon.
Posted: Mon Mar 31, 2008 8:56 pm
by daberno123
Very Nice!
Easy, simple, and user-friendly. A lot less confusing than other calculators I've tried to use. Good work!
Edit: what else are you planning to add?
Posted: Mon Mar 31, 2008 9:21 pm
by pat123
a way to find chamber and barrel volume. Do guys see anything else that I should add? I updated it a little, I'll post the new version tomorrow.
Posted: Mon Mar 31, 2008 10:16 pm
by jon_89
This is great. Quick question though. A 1x mix is just regular combustion right? I would suggest maybe doing half mixes like 2.5x or 3.5x mix because I see many people doing this.
Posted: Mon Mar 31, 2008 10:31 pm
by MrCrowley
Cool bananas, will test it soon
Edit: Just noticed the equation uses .953, now I could be wrong here, but glancing over SB15's topic, which I think you based this off, he used .958 for propane...
There's probably some crystal clear explanation I just looked over.
Oh and I also made a second sheet for MAPP gas, as i'll probably be using that.
Thanks

Posted: Mon Mar 31, 2008 10:43 pm
by SpudUke5
I got slightly different results:
For 100 ci chamber
25 ci volume of pressure meter.
My program:
For 3x, i got 7.73 psi
For 4x, i got 10.3 psi
Your program:
3x i got 8.69 psi
4x i got 11.59 psi
Just slightly off but i could make a big difference.
Posted: Mon Mar 31, 2008 10:57 pm
by starman
Your calculator predicted a little high on mine too, 74 psi. I predicted and have been using 63 PSI. 225 CI chamber, 2.2 CI meter. My calc may be wrong, I'll check mine again.
Posted: Tue Apr 01, 2008 3:22 pm
by pat123
I just uploaded a new version.
Edit: Just noticed the equation uses .953, now I could be wrong here, but glancing over SB15's topic, which I think you based this off, he used .958 for propane...
thanks i just changed that. by the way thanks to SB15 for all of the formulas in the first place
This is great. Quick question though. A 1x mix is just regular combustion right? I would suggest maybe doing half mixes like 2.5x or 3.5x mix because I see many people doing this.
yep 1x is normal combustion. I'll add those too.
Oh and I also made a second sheet for MAPP gas, as i'll probably be using that.
If you don't mind giving it to me Ill add that to it too.
Posted: Tue Apr 01, 2008 3:36 pm
by Hubb
This thread reminds me. I need to update my CO2 calculator thread.
Pat, if you want, I can send you a copy of mine so you can add to this. I posted the original a while back, but I have since made updates to it, including more accurate CO2 data, as well as high pressured air data. If you're interested in throwing in a little pneumatics with this, just let me know.
Oh, and have you considered adding butane to your spreadsheet. A lot of members use it, too.
Posted: Tue Apr 01, 2008 3:41 pm
by daberno123
Just downloaded the newer copy. Only complaint is the yellow background...my eyes...they burn.
Oh and you should definitely make different sheets for different fuels
Posted: Tue Apr 01, 2008 3:46 pm
by pat123
I'll take co2, air, butane, etc. just need a new name.
Posted: Wed Apr 02, 2008 8:00 pm
by pat123
I updated it now it works for mapp, propane, and butane. I need someone to check over it and make sure it is right for butane and mapp gas.