Most power gravity feed with alky

[durandbagwell86]

I was wondering who has the most power/fastest ride that's gravity feed with methanol? I know it uses a large volume of alky but I'd like to run my setup with gravity, 1/4" outlet on the tank with 1/4" fule line to the carb. It's a 460cc big block that'll only be ran 1/8 mile drag and turn 7500-8500 rpms. It did fine on gas gravity feeding on my boat but not sure how it'll do on methanol. Thanks

 

[massacre]

I tried gravity feed on my small block alcohol motor, I had better and more consistent results with a fuel pump.
I can only imagine the same would be true for your engine because of the size, maybe even more so.
It’s a lot of fuel and the Gs of the bike can change the fuel flow.
Any reason you don’t want to run a fuel pump? They are pretty cheap and easy to use and work great in my experience

 

[durandbagwell86]

I have a fuel pump. I'd like to gravity feed the engine. The nitrous kit will have a standalone tank and electric pump for the fuel side. If I have to run a pump I will.

 

[massacre]

I have a fuel pump. I'd like to gravity feed the engine. The nitrous kit will have a standalone tank and electric pump for the fuel side. If I have to run a pump I will.

Ok gotcha
Did not know this was a nitrous bike
We installed a nitrous kit on my Dad’s drag bike, we ended up using both fuel pumps.
But it may end up working ok for you to just use the one.
Only way to tell is to try it, when we did it didn’t work too well but each situation is different

 

[durandbagwell86]

Hopefully it'll turn out alright. It'll be strictly a drag bike so I'll do pleanty of testing.

 

[Havasu Dave]

Sounds like a good excuse to use a Tillotson. How are you guys going from lean to rich when you hit NOS, or are you just dealing with rich condition until you hit it?

 

[massacre]

Hopefully it'll turn out alright. It'll be strictly a drag bike so I'll do pleanty of testing.

That really is the key. There’s no easy way lol

 

[massacre]

Sounds like a good excuse to use a Tillotson. How are you guys going from lean to rich when you hit NOS, or are you just dealing with rich condition until you hit it?

Hey Dave!
Ours is a simple wet system. The kit we bought came with 2 solenoids, 1 for the NO2 and 1 for fuel. It comes with an extra fuel pump and relay and when you hit the switch it activates the extra fuel pump and both solenoids.

 

[Havasu Dave]

Hey Dave!
Ours is a simple wet system. The kit we bought came with 2 solenoids, 1 for the NO2 and 1 for fuel. It comes with an extra fuel pump and relay and when you hit the switch it activates the extra fuel pump and both solenoids.

I see, thanks! I kinda drove off topic here, but I figured with all of the years you've been doing this now, you'd have a good answer. :thumbsup:

 

[durandbagwell86]

Yep. Wet kit with a standalone fuel system for the solenoid.

 

[65ShelbyClone]

Wet kits really are the best way to employ nitrous IMO. :thumbsup:

If I were to approach the original question scientifically, I would get the gravity system set up the way you want it, then measure the flow out of it all the way through the float valve, ideally mass over time at a consistent temperature. From there you can estimate how much power the flow will support, compare it to how much NA power the engine is expected to make, and then determine if it is enough flow to supply the engine with some safety margin.