| Its been a little while since the last update on the project and have a few tidbits to share. Rolling into 5400 miles it was found that the Noltec urethane engine mounts were sagging and the top mount plate had debonded from the urethane on both mounts. This past father's day weekend (happy father's day BTW to the dad's out there!) I made the trek over to Gainesville and Brevard Motorsports was holding another track day at the roadcourse that I found out about late tuesday night. Desperately needing engine mounts for the trip/track, I set to work Wednesday afternoon around 5 and built the mold patterns for the new mounts and cast the parts. They were done and the car ready to roll out for the trip the following day around 7PM or so. 
I went to a local speed shop and picked up some urethane a-arm bushings that were appropriately sized. $13 each.
After casting the first set of parts I saw a little room for improvement. I remade both patterns: the base having cutouts on the radius to minimize casting shrinkage and the "U" shaped bracket was made with longer legs to provide full face contact with the thrust flange of the bushings.
 
Assembly complete. The top and bottom flanges were drilled/tapped with M12X1.25s, a stud installed into the top U-bracket.
 Installed. A bolt was used to secure the mount to the subframe and a self-locking nut was used on the top stud in the mount.
Given the rigidity of this design vs. the large "cushion" noltecs, you can feel the engine a bit more. It is a crisper feel when alternating between a power on and power off states - the engine just isn't rocking around in the bay as much. I can now feel some vibration harmonics in the engine as well at various RPMs - pretty interesting dynamic but nothing out of the ordinary. It was a little surprising at first but it definately has that tight race feel and crispness. Thumbs up.
I'm looking forward to seeing Jim Selin release his new engine mounts - for all intensive purposes my mounts are identical to the design he is using and I have been/will continue to provide feedback to him on their performance. I have no interest of reproducing the mounts I made so please send any questions, comments, etc, to Jim himself (CaliguyPurdue) jims@hi-tempinsulation.com - I support his endeavours and am happy just to be a part of it. End result: Car did well at the track - the street tires obviously being the limiting factor but it was fun no less to drive her as hard as possible without incident. I just switched over to synthetic given I'm past the 5K mile marker but I will pull the mounts on the next oil change to inspect them. There are about 340 miles on these mounts so far including the roadcourse event with two 15 minute long runs. I would like to find a dragstrip within reasonable distance and finally put her through that trial. Among a ton of other things, it will be a good test for these mounts. We'll see though.. :)
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AshsZ-II Ultimate Street Z Project: Engine mount fab > - 
