Nitro scramble button setup

[johnnydmd]

Are you activating it on the starting line or is it on a radio switch?

Radio switch. In theory you could hit it off the line (wouldn't recommend doing that with a big block), and let off the button, and hit it again if needed. It packs quite a bit of NO2 in the expansion chamber.

 

[Greywolf74]

Finished the system this weekend. Had beautiful weather on Saturday for testing, but I was short one (major) part, and didn't finish until last night. Next week looks like we have a chance for some near 60 deg temps on Saturday, so maybe then.

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I did adjust the valves and test the duration. I got about 4 seconds of boost in total, without about 3 of those being strong. That's more than enough and gives me a lot of room to adjust the flow.

The system is actually very lightweight, aside from the metal cartridge and regulator. The cool thing is once you've used that to charge the expansion tank, you can take it off to save weight, as the system cannot backflow because of the Shrader valve.

you're a madman bro! I love it!

 

[johnnydmd]

Started on another one last night. Waiting on the gauge to arrive to finish it.

The system as shown with what is on the car during a run, weighs in at a whopping 2.8 oz That's pretty light given the power increase. The key to this system is that the cartridge and regulator don't need to be attached to run, as they add quite a bit of weight.

 

[johnnydmd]

So, the jury is in on this setup, it works extremely well. (see the "Hissed Off" thread for a recent video that demonstrates it vividly) Here is one that is fully finished:

Note, I did replace the purge valve at the bottom of the pic with a better one, as those plastic ones leaked, slightly.

After testing this in both a big and small block, and noting that the small block got a vastly larger power increase, I have determined that the big block version will need a larger tank, so I have a 4 inch tube coming to replace the 2 inch one shown here.

 

[9x19]

Well done!

Great job getting it all sorted.

 

[johnnydmd]

One practical revision was done - and that is to run the charge valve and gauge out the rear where it can be accessed with the body on, to facilitate re-charging the system after a run without having to remove the body. I considered moving the tank and switch to the rear as well, but it would have been a bit too cramped and would rather not upset the car balance any by adding 80gs behind the rear axles.

I also made a larger tank for the big block car, as I think the small tank didn't provide enough boost after seeing what it did with the .12 engine.

 

[Doom!]

Smart move moving the gauge to the rear. I knowed you weren't no dummy.

 

[johnnydmd]

Finally, after so much trial and error, I was able to get a much better solution for charging the car with nitrous.

It's pretty simple to do. Attach the regulator at the end of the hose to the car's shrader valve (this regulator is just left open), and then use the main regulator to release gas into the car. One, it's way less sensitive than using the little regulator on the 12g rechargeable cannisters and get the right amount in without overcharging it(and potentially blowing hoses off, etc). Two, I can now see how much is left in my nitrous tank.

The 1/2 inch short PVC tanks I made are perfect for the .12 sized engines. They are too small for the .21 engines. The really long one was too much. So I made a shorter 3/4 inch one for the .21 sizes. This one seems perfect.

 

[Doom!]

I love how you are always coming up with better solutions.

 

[johnnydmd]

Little video showing how a race is run using this thing. I was late hitting it, which didn't cost me the race, my opponent dialed in a 3.49, and he ran exactly 3.49! I had dialed in a 2.7 and ran a 2.8, if I'd have hit it earlier, I probably would have busted (gone under my dial-in) out and lost. Can't beat perfect