My RCGF 40cc twin has a fair amount of fuel being sucked out while running.

would a velocity stack fix this issue? if so, what model would you recommend?

other options?

sgt;yes,I have the 40 on an in cowl 1/4 cub and stopped the spitting.

What model 1/4 cub is that on?

a sig full wing,I like the extra power cause I fly on floats as well.

wow. I have a BUSA 1/4 cub I thought about putting it on, but seemed way too much for it.

could you post a pic or two of the plane?

thanks

busa's cub is slitely larger than a sig.sig has a 105" wing busa is 108" wing the fuses have a 1" difference,your cowling is larger.the heads get plenty of cooling on mine.yours will too.try it you mite like it ,I do.

Thanks. I may do that.

Would ls still like to see some pics if your cub.

What prop are you swinging on the RCGF 40 twin?

sgt;I dont have the means to post pics first no camera second I dont have the slitest idea of how to put it on hear.I am turning a 20-6-10 xoar prop.

Ok

thanks

I guess since no one mentioned it already, a intake stack being about 1 to 2 inches long would work fine. I have been using them on several engines too. The straight cut type with a angled end works well. But one could use a tapered horn like shaped intake stack too. They sell several of the straight intake statcks with a angled cut on the end that work pretty good and you don't have to carve up the cowl too much for them either. Great Planes sells one (a velocity that would work on your 40cc engine OK. The intake or velocity stack helps to stabilize the air fuel vapor cloud that forms at the entrance to the carburetor and it also smooths out the air flow, that varies a lot as the plane is moving around, going past the carb which causes uneven running. Thus the engine tends to run better and any spitting out of the carb is kept inside of the stack instead of getting blwn back over the plane. If you look at the Walbro carbs, you'll observe that the main jet orifice is neat the front entrance to the carb, so it can be sensitive to the fast flowing air going by as the plane is flying.

Here is one on one of my gas engine powered planes shown in this pic.
http://i248.photobucket.com/albums/g..._engine_04.jpg

Thanks. Ever used one from 3W?

namely the 90 degree version?