So there have been a few different ways people on here have raised their rear mounts. Here is my way. I will be able to adjust my roll center by shimming the pickup points on the mount. I will also be able to adjust camber separate of the roll center. I have a few more braces to make before it is all done.

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.........well BAM, what ever happened to the exhaust system you were mocking up?...It looked simple-direct -and functional.(usually a good sign something will work good).....Curious?? .........Murray

The exhaust worked great! It sold with the engine that was in my car. Nothing like getting 108whp and 125ft/lbs out of a "stock" FI 2.0L

...........So are you going to make another one or two?.....intrested......M.M.

Just my non-engineer .02.
Were it me, I would put the hiem joint attach points in double shear using a C section and tie in the supports at the same level of the pivot point.
Your present set up gives the applied forces a mechanical advantage over the structure intended to hold it. Overall, I like the concept but, as is, doubt it's integrity.

Like I said I have not added the rest of the braces. I am putting the heims in double shear and adding a couple more braces. It should be fine. But I am no engineer, just a high school graduate.

The only thing that kept me from going to college was high school......so I went to the school of hard knocks for 40 odd years.

After working in various types of construction (planes & boats & trains), like to think have a good eye for how good engineers do what they do. I know you're not done so I fingered I'd get my .02 in before hand...not being critical, tho my form of attempting to help can be seen as so.

I appreciate the $.02. I like getting other peoples ideas and concerns when building some of my stuff. I have thought hard about how best to brace the mount. When you see what I have planned it should not move. It already is pretty stiff just being tack welded together.

The rear suspension on the 914 has never been an issue. Go back and look at all the old IMSA racers. They left the rear pretty much alone with the exception of stiffiners. The key to roll center on the 914 is the front suspension. No different than 911's. 935 style aka ERP is the ticket.

That is not entirely accurate. The rear suspension has always been a problem. The front and rear suspensions roll in different directions, the toe curves are radically different thus contributing to weird handling in race trim. The rear suspension is weak and goes from bad to worse when you stick big race rubber on it.

All of the top running IMSA cars move the rear suspension points up, the back markers left them alone.