Hi, I have the same dilemma of Daniel (dserberin) ?. I?m building an RV-7. Now I?m building the empennage kit. I am at the point where I would like to buy the QuickBuild Kit. Compiling the Van?s RV7 Quickbuild Order form, in the Finishing kit section I must select the engine: O-320-D1A, O-360-A1A, IO-360-M1B or IO-360-A1B6. I?m already flying an RV7 which I bought already built. I have decided to build one from scratch by myself and if I?ll succeed I?ll sell the actual one

. My RV7 has an O-360-A1A that goes fine. Fuel consumption is 33 Lt/h (8,7 gal) and oil consumption is 1,2 Kg/10 hours (1,26 quarts/10 hours) it cruises at 150 - 160 kts at 75%. But I would like to go for the injection mainly for doing some aerobatic ?. so, my dilemma is between IO-360-M1B 180 hp and IO-360-A1B6 200 hp.
First, what is the reason for asking, may be is that the engine mounts are different? also the cowling?
I saw the Bill answer telling that there is only a small difference between the cruise of the 180 hp and 200 hp and that is also less expensive and lighter?. But any other suggestions?
Thanks for helping me in the choice ?.