In another thread someone was talking about using a longer line going from the pipe to the tank to get greater fuel pressure. does this actually work. and if so, how long should it be to get a lot of pressure. Thanks
-
Welcome to RCTalk! 🚀
Join the #1 RC community where hobbyists connect, share, and get expert advice on RC cars, trucks, boats, drones, and more!
- ✓ Friendly & passionate RC enthusiasts
- ✓ RC tips & troubleshooting
- ✓ Buy, sell & trade RC gear
- ✓ Share builds & upgrades
fuel tank pressure
- Thread starter dpk136
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.
links, including eBay, Amazon, and others.
7 in is the length u should start with. By making the line longer I think it makes the engine run richer and by shortening it is makes it run leaner. I think that is bass ackwards but I'm not sure someone tell me if I'm wrong or not. I always just make it he perfect length to go from the pipe to the tank in the rote that it needs to go and don't really pay much attention to it, and why would you want extra pressure?
well, it depends on how your engine or pipe specifies they will vary. You can't just have the exact length you need to reach some say you need 6 inches from the tank to pipe, some say 4 inches, it all depends its best to leave them at stock or what it says in your manual.
Lengthening the line evens out the pressure pulses that come from the exhaust. Making it too long will lower the pressure. Making it too short will probably cause excessive foaming.
- Messages
- 8,360
- Reaction score
- 13
- Points
- 758
- RC Driving Style
- Bashing
dpk136 said:
The pressure line from the pipe to the tank should be between 6 and 9 inches in length. If you go longer than that, you will decrease the pressure to the tank and create an artifically lean condition. If you shorten the line, you will increase the pressure to the tank.
So, if you want more pressure without detriment (ie foaming fuel) try the 6 inch length. If you want to even out the pressure to the tank without going too long, try the 9 inch length.
Note, this rule of thumb applies mostly to .15 sized engines or above and is proven in MTs, buggies, and some onroads. You will find that there are several people who run much shorter lengths of line and have no problems.
- Messages
- 35,104
- Reaction score
- 1,858
- Points
- 2,198
- Location
- In my recliner
- RC Driving Style
- Bashing
- Flying
6 - 9 seems to be the rule of thumb. I'm at about 7 with a Big Daddy fuel filter in the middle. Another advantage of this setup is more lid time without stalling out, since there is more fuel in the line and the large filter.
Rolex said:
Correct me if I'm wrong but we are talking here about the length of the pressure line between the tuned pipe and the tank, not the fuel line between the tank and the carb.
There's a school of thought that says that increasing the length of the pressure line delays the build up of pressure as the throttle is opened and engine speed increases. If you are getting a massive cloud of blue smoke as you open the throttle up then lengthening the pressure line might reduce this somewhat.
Last edited:
- Messages
- 35,104
- Reaction score
- 1,858
- Points
- 2,198
- Location
- In my recliner
- RC Driving Style
- Bashing
- Flying
Sorry, I didn't finish the thought. I'm running the same on both lines. Fuel and pressure. I can hear it go lean within 10-15 seconds of shutting down. Other than that, it runs consistantly for the entire tank.
- Messages
- 35,104
- Reaction score
- 1,858
- Points
- 2,198
- Location
- In my recliner
- RC Driving Style
- Bashing
- Flying
No. Just the same length on both. Filter on fuel line only.
- Messages
- 8,360
- Reaction score
- 13
- Points
- 758
- RC Driving Style
- Bashing
Total run of fuel tubing should be between 12 and 18 inches. That includes tubing from pipe to tank and tank to carb. The shorter the line from tank to carb, the richer the engine will want to run and vice versa.
You can experiment with various combinations, but most people run things a bit longer on the tank to carb to allow for more lid time without stalling. They tend to compensate by shortening the pipe to tank line a hair.
In the end, as long as you stay within those numbers you should be good to go.
You can experiment with various combinations, but most people run things a bit longer on the tank to carb to allow for more lid time without stalling. They tend to compensate by shortening the pipe to tank line a hair.
In the end, as long as you stay within those numbers you should be good to go.
