Never had one overheat... N20 going through there keeps the whole solenoid cool, however we have experienced a small solenoid freezing and not releasing when you release the button.... fuel shuts off, N20 does not... want to guess what happens next
Yea, they never had that happen before.... so much for their kit... we bought the biggest one we could find and never had that problem again. It took about 2 years for us too develop our own system with jetting schedules and pressures to run without regular failures... Fat is your friend.... and you only loose a few HP running too fat, which is way better than loosing a few parts running too lean.
Without finding my old notes... from the late 90's to 2001 (the last time we ran N20) 50 HP for 30 seconds is about 2.5 lbs of N20 and .5 lbs of fuel to stay at a safe mix of 5:1. Rule of thumb... 1lb a minute = 10 HP... although better motors make better numbers.
Testing the system outside the motor is your key to success. If it works when not attached to the motor, your chance of success goes up. When I say outside the motor, I mean set up your system to fit your motor, then remove the entire system and run it outside the motor... N20 and fuel with the components you use on the motor. Yes, I mean everything, tank, valves, pump, hoses.... everything. You are about to go through a bit of N20, but believe me, testing is way less expensive than race motors.
Weigh your bottle, use the best digital scale you can get... a food scale that measures to a 1/10 of a gram should be OK... we borrowed a scale that read .0001 and that was a bit of overkill.
1. run the N20 through the jets at the temp and pressure you expect for exactly 60 seconds...your bottle write down your results for each jet... recording temp and pressure, if they all seem to run the same refill your bottle and go to step 2....
2. run the set of jets for exactly 30 seconds... this is the amount of N20 you expect to use in a run. Again weigh and record also note bottle pressures as you spray... if you do this in a small enclosed room you will be happier with your results
3. Now for the fuel... Weigh a container that is fuel safe, and run jets one at a time, note fuel pressure throughout the test for consistency of data. Again, you want them to spray the same weight at the same pressure... write everything down.... write everything down
4. Now run them together for 30 seconds... this is the amount of fuel you expect to use in a run. Monitor pressure throughout the run.
Write down the weight.
5. Time to do a little math with your data... if you divide the N20 weight by the Fuel weight that gives you your ratio. Safe/Fat is 5... dangerous/lean is 6. There is also a too fat that is just as bad as too lean... so you may end up with multiple sets of jets to mix and match to go faster. Remember if you need more fuel, that is more pressure with the same jet.
Test, record, test record...... Your test setup must be your run setup... end to end
Spark... retard it, how much depends on the motor. I'd probably start with 5 degrees. Watch your plugs... consider retracted gap, that eliminates a hot spot
If you have access to a dyno use it...
everything I have written is based on my experience injecting liquid N20.... Your experiences could be different... did I mention test, test, test
Ok, the playing field is level... everyone knows what to do.... go for it
