QUESTIONS ON CASES

I just bought a motor, and here is the question that I have. When I looked at the cases I realized that one half says 5r and the other says 7r. Now i've been told that they are probably mismatched and could cause you problems. What type of problems can I have and any suggestions.

come on guys help me out on this one

The 7R case is considered the strongest of the early mag cases because of additional webbings cast into it to reinforce "weaker" or problem areas. This does not mean the other cases will blow up automatically. If you have a mismatch it should not be a problem if the machining was done correctly when the engine was built. I would only be concerned if you plan to use the engine in competition.

but how do I know if they are mismathed? I was told that the motor was running. Am I going to put it back together and find out that I will have all sorts of problems with it. and what type of problems.