SonexBuilders.net

Hello all,
I'm about 9 hours from flying off my 40 hours and are still working on "tweaking" things. My Tri-gear Sonex flys great and I'm very pleased with the plane. I'm working on getting my CHT & EGT's closer and lower on my GPA 2276cc VW. There is not much front to back spread, but the right side runs high CHT & EGT's. I have tried to balance the fuel/air right to left, but think the problem is better air flow and cooling on the left side vs. the right side. I have read that the geometry of the cowl & prop rotation has more air in the left side. I'm considering adding a baffle or dam above the engine to move some left air to the right side. Has anyone tried this and what was the result?
Thanks for any comments or feedback.

Craig Hoskins
Sonex no. 1537

Just out of curiousity Craig, what sort of carb and intake setup to you have? Do you use the AeroInjector or something else?

Mike,
I installed a Rotec 34-2 TBI along with fuel pump & filtration. There is a full time air filter at the TBI inlet with a damper for ram air or carb heat air. I originally had a problem with the engine running only lean of peak after takeoff. It turned out the Rotec 34-2 is designed for up to a 2100cc engine (mine is 2276cc), so I had to open up 9 of the 48 fuel bar holes to increase the fuel flow. I added a turbulator between the TBI & the flange of intake pipe to the cylinders, to improve the mixture to the left & right sides. I'm pleased with it's performance now, but would like to reduce the CHT 28F spread right to left & the EGT 24F spread right to left. I'm thinking improving the cooling balance right to left is the next thing to do.
Craig Hoskins
S/N 1537

I had a problem much the same as yours. I added a small "ramp" in front of the right cylinders. Worked reat
JACk
N369UR