Motor mounts are back

I picked up the motor mounts from the powder coater earlier this week. The one that appears to be shorter is for the passenger side. Like I said before the drivers side needs a spacer at the engine in order to use a flat plate. You could also contour the plate on the engine side to get rid of the spacer, but that makes attaching the tube for the cross member more difficult.  Fitment on the passenger side is really close to the starter.  I didn't actually try to pack it in this tight, but it will leave plenty of room for the 3" exhaust.  Fitment on the drivers side is good also with plenty of room for the steering shaft.
To make these I made tracings of the original AAN mount by gluing card stock to them and cutting it with a ball peen hammer.  The same way you would make a custom gasket.  Then just move the patterns to some .250" plate steel and cut them out.  I created the feet with some paper and a compass while watching television.  Transfer the pattern to some .250" plate steel and cut them out.  Next I mounted all the pieces and positioned the motor with an engine hoist.  Using PVC pipe that was close to the size of my tubing I made some mock ups.  Its really fast to work and cheap to start over if it doesn't work out.  After that you just recreate them with your .120" chromoly tube and weld it all together.  It doesn't take any special equipment other than a welder to do this, just some patience.  Now I can drop the motor back in and start the exhaust manifold. 

 

  

 

Motor mount drawings.

I have gotten a request for dimensional drawings of the motor mounts that I came up with. Sorry to say that I don't have any CAD drawings of them. I'm more of a make it by feel person when it comes to one off parts of this nature. I can tell you though that I attached some card stock with spray adhesive to the original Audi mounts, then I used a ball peen hammer to gently punch out the bolt holes, after which I transferred the the card stock to .250" thick plate steel and cut out the rough shape. Once both plates where made I bolted them to the motor. The drivers side mount is more involved because the original mount is z shaped. Making a z shaped mount would have proven difficult for me plus there was an issue with a bolt hole being covered by the support tube. I ended up making the mount from flat stock with a standoff welded to the backside of the mount to compensate for the original z shape. This also eliminated the problem of the support tube covering a bolt hole. How you make the feet will depend on which motor mount you decide to use. I recommend something very hard to really limit movement of the motor, there just isn't enough room around the motor for it to be swinging about without hitting something. After I made the feet and had them mounted where the original Porsche mounts where, I used PVC pipe to quickly develop what the connecting pipe should look like. Once that was done I made a new one in .120" x 1.500" OD tube and welded it into position. I started with the passenger side mount and then the drivers side mount. Things to be aware of are that the motor doesn't' want to hang from the hoist at the right angle. I used a ratchet strap to correct this during mock up. Also repeatedly make sure that your height and lateral positioning are correct during the process. If I remember correctly it was 13.5" from the crank bolt to each frame rail to keep it centered. The height has a very small window in which the pan will not hit the frame, but the hood will still close. I will measure it again, but iirc the bottom of the lowest point of the block needs to be 1" from the cross member, this will leave about .500" for the passenger side of the oil pan and .500" for clearance. Take all this with a grain of salt though as I am in the process of making the pan right now and will make updates as problems arise. I will post pics of the mounts when they are removed for powder coating, that should help out if there is any confusion.

Motor mount pics

Here are the pics that I promised.  I wish that they were better, but it is hard to fit my camera in there.  I will put up some more when I have them powder coated for the final installation.  First is the drivers side, second the passenger side.

Motor mounts finished

I finished up the motor mounts today and I think they came out pretty nice.  The actual isolation pad is made from polyurethane.  I figured that the weight of the motor would compress them some so I tried to compensate by hanging the motor a little higher than I wanted it to actually be.  After completing the mounts and lowering the engine into the car they didn't compress like I thought they would.  I have 1 inch of clearance on the p/s of the engine for the oil pan, but I'm worried that the hood isn't going to close now.  I really wanted the exterior of the car to remain unchanged.   I could probably have some of the isomounts shaved off at a machine shop and still use the current engine mounts. 
I also cut the reservoir off of the donor oil pan to make way for a 944 like sump.  Since I have a weeks vacation starting soon I should wrap that project up pretty quickly.
One last note is that I have located a HY35 and it is en route, so we'll get to see if that will fit under the hood also.  If rumors are correct I should be able to hit my horsepower goal of roughly 400bhp.  It will be months before we learn the reality of the situation though.  As there is much to complete first.  I will post pics of my mounts soon and the turbo when it arrives.