Have a G-62 in a 19lb Kange Laser2000 w/ 22-10 Bambula prop.
I'm getting 6450 RPM on the ground. If I use a velocity stack will the "R"s improve? Which way to point the opening? Towards the back, front, up, down, or does it matter? Would like to hear from anyone with experience with this set up. Thanks all !!!!!!!!!!

I have one on my G62, pointed forward for so the prop blast acts like a ram effect. The main reason I did this was to keep the fuel from being spit back out of the carb. Tends to make a mess on the plane. My G62 (C&H Ignition) spins a Zinger 22X10 @ 7200 rpm. Hovers my Giant Stinger around 1/2 throttle.

Velocity stack won't give more power, just better gas mileage and less slop inside the cowl or on the fuse.

Thanks guys......Flypaper, which way is your stack facing?

In most cases, you do NOT want ram air in the carb. The purpose of the velocity stack is to minimise blow out of air/fuel mixture at certain portions of the combustion cycle. If you point it into the airstream you will likely have problems getting a consistant needle setting for all conditions, it will change between ground tests and airborne use. I can't remember for sure where I saw it but think it was in one of Clarence Lee's writeups explaining the purpose and best use of the velocity stack. Now, if you have the engine completely cowled in with no direct outlet at the carb, you may find one position is better than another for the velocity stack due to the circulation pattern inside the cowl.

Thanks Rodney. You just confirmed what I thought.

Snaproll717

I have no problems with my setup. It seems to run better than without the stack. I actually got the idea from an internet article about Quadra engines. They used copper tubing and claimed the ram air to give a small performance boost. Don't know about the boost. But, as I said mine does seem to run better.

Mine are not cut off on an angle. They stick straight out like a bell.

I have a G-62 in a 29# Sea Fury. Flys the plane real well and I needed the nose weight. Engine is fully cowled so air to the carb only comes in from the cowl to spinner opening. Was getting real bad carb blow by(fuel all over the inside of the cowl). Engine was on the rich side, don't want to overheat and dead stick a 20# warbird. Turned a 22X10 Master air screw @ 6700. I added the B&B stack and the oil mess stopped totally. New RPM was 6300. Engine was now way rich due to fuel going down the carb and not out into the cowl. Have tweeked the needle and now have it back up to 6500. I will give it another 1/16th turn in and see how it goes.
Plane was clocked by radar gun flat and level at 96 mph with only 6500RPM so I' am not after more speed just a better fuel ecomomy setting. W/O the stack I could only stay up 10-12 minutes before starting to land on a 24 oz tank. Now I get 15 -16 min. with 4oz of fuel to spare.