At 09:38 PM 5/4/2016, you wrote: > From memory there is a 3 or 4" shelf across the back (inside) of > the firewall and the O_200 mount I have bolts just below this. +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
If I read this correctly, your top engine mount bolts do not pass through the top spruce cross piece but thought the 1/4" ply firewall. If that is correct it is not good. The top and bottom mount bolts should pass through the upper and lower spruce cross members and use a crush plate of some type on both sides of the wood. The firewall does not need a great deal of "beefing up" to support the 0-200. Marty Roberts started with a VW and plans built firewall and later installed an 0-200. On more than one occasion he pulled 6 G's and the 0-200 continued to point the way home. Larry Flesner
