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BIG G
03-30-2005, 03:37 AM
We are going to use a 20 oz canister of CO2 this year on our car. Was wondering if any other teams using this size of gas canister could tell me how many gear changes you have sucessfully achieved from this size of canister. Info much appreciated.
BIG G
03-30-2005, 03:37 AM
We are going to use a 20 oz canister of CO2 this year on our car. Was wondering if any other teams using this size of gas canister could tell me how many gear changes you have sucessfully achieved from this size of canister. Info much appreciated.
EgyptianMagician
03-30-2005, 12:32 PM
rough guide....
pv = nrt .... you can get a close number, and then say take off 30% or what not for line expansion etc ... or maybe 50% for safety sakes
Chris Clarke
03-30-2005, 11:33 PM
pv=nrt only applies to gases, not liquids (CO2).

I am not sure the exact size of our canister, but I think it is 20 oz.

A couple of years ago a couple of guys spent about 1/2 hr shifting the shift cyl up and down (not attached to the tranny), and got a number of about 1500 shifts from a full tank of CO2. You can definitely get a day or twos worth of testing off of one tank. Just make sure that you check it before each test day, and that all connections are tight. We lost our shifting in the endurance last year because someone didnt make sure all the fittings were on properly.
Igor
03-31-2005, 02:51 AM
1 gram of CO2 is about 0.5 liter at atmospheric pressure. You can then calculate how much grams you will use depending on your pressure, cylinder volume and line volume. Try to keep the solenoid as close to the cylinder as possible to not waste too much gas.

Igor
BIG G
03-31-2005, 03:31 AM
dank u velle
gug
04-02-2005, 07:30 PM
here (http://www.paradigmmotorsports.com/html/notes.html), an ex. cal poly pomona says that they got 1400 shifts out of a 12oz CO2 tank.

we went with a 12oz, and while i never tested how many shifts we could get out of it, we never came close to emptying it. i would say that a 20oz is an overkill. i would actually go for even smaller than 12oz in the UK, but in australia we need to underfill our bottles to stop them over-pressurising in the heat.