Tank Sizing

[Phil Coopy]

Now that I am getting close to finally completing the last maneuver in the full sequence, have increased fuel tank sizes twice, and again I'm getting dangerously close to empty. I am running an LA40 with 11.5 - 4 ProZinger prop on Fancherized Twister at a rich 2 cycle.  Combo runs great, good lap time, but drinks about 4 oz before the cloverleaf.  What size tank does it normally take to make the whole sequence (with a little to spare) using a 40 size engine?

Phil

[Wynn Robins]

I use the LA46 - it uses a little less then 4oz o complete the entire pattern with around 4-5 laps after the clover leaf -

Interesting that you get less - however - what % nitro are you using?  I use 5%, 20 % oil

[Mark Scarborough]

On my LA 46s (and several others around here) a difference of 300 to 500 rpm can make a HUGE difference in consumption. that said, I use about 4 oz at home 2500 foot elevation and about 4.25 to 4.5 oz at contests, 300 feet elevation. On my FP 40s I generally get by with 3.75 oz at home, and about 4.25 to 4.5 at contests. My LA 46 I run an APC 12.25 x 3.75 prop my FP an APC 11.5 x 4 or an 11x4.