HCMP

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pat123
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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
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Last edited by pat123 on Wed Apr 02, 2008 7:58 pm, edited 2 times in total.
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Counterstriker
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Picture not working for me.
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bigbob12345
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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 :lol:
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pat123
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Thanks it only took about 5 minutes to make. I am going to add some more stuff to it soon.
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daberno123
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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?
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pat123
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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.
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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.
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MrCrowley
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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. :roll:

Oh and I also made a second sheet for MAPP gas, as i'll probably be using that.

Thanks :)
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SpudUke5
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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.
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starman
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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.
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pat123
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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.
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Hubb
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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.
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daberno123
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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
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pat123
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I'll take co2, air, butane, etc. just need a new name.
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pat123
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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.
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