This is a good post! Very relevant!

After having dozens of models with engines mounted in every conceivable orientation.....I would say the side mount is perhaps the preferred method for me.

Easy to route the exhaust under the model. Easier to get the carb/tank centerline in alignment. The cylinder never acts as a sump to cause flooding/starting/loading up problems.

Nobody mentions the effect of G's on loading up an inverted engine in flight...it happens!

Side mount seems to work real well.

'Race