Engine: Verner 3VLA

[Chuck in Indiana]

I wish I had one of those benders, so I can't tell you what it will do. My engine mount holes were some weird metric size between 5/16" and 3/8". I reamed it out to 3/8 to use AN hardware. You want the bolts to fit the case pretty well.

[Brock]

I wish I had one of those benders, so I can't tell you what it will do. My engine mount holes were some weird metric size between 5/16" and 3/8". I reamed it out to 3/8 to use AN hardware. You want the bolts to fit the case pretty well.

On the 3VLA the bolts don't fit the case but the mounts.  The wrong mount that was sent to me was setup for 3/8" bolts.  I think that is what my 200 HP lycoming takes while the 85 hp on the sonex uses 1/4" bolts.  I was wondering if 3/8 was just overkill and if 5/16" would provide enough of margin.  Bigger bolts = more weight.

[Chuck in Indiana]

Oh, I'm sure the 5/16" are plenty, but I didn't want that less than turbine smooth Verner wallering out (Indiana term)  those holes in the case if the bolts don't fit well. At least that was my reason for reaming to 3/8".
Now.. your engine is completely different with the rubber directly against the case.. and I'll bet you have enough experience to make the call.