JMortensen Posted March 17, 2014 Author Share Posted March 17, 2014 I looked at that and running the shaft through the mount wasn't an option. Yesterday I made the frame rail reinforcements and I'm pretty comfortable with how it ended up. Need to clean up the rails and weld them on, but I'm thinking it's going to be fine. The outside part of my reinforcement will go down to the plate that reinforces the stock rail where it bolts to the xmember. On the inside I have a big reinforcement that goes on bottom to strengthen the TC rod boxes that I welded on. I see two outside possibilities now. 1. The frame rail still manages to tear apart as the engine lifts on the driver's side. If this happens, I can put a bolt through the bottom of the rail and leave the stud sticking out the top and put a nut on top instead of a bolt going down into the rail. 2. The flat bottom on the tube that's bolted to the rail isn't strong enough and it starts to tear. If that happens I'll go with Coffey's suggestion and make the mount a Y so that I spread the load. Quote Link to comment Share on other sites More sharing options...
heavy85 Posted March 18, 2014 Share Posted March 18, 2014 Jon - more I look at this and Im worried about the whole front frame rails flexing excessively without some lateral and vertical support that the inner fenders would have normally provided. The factory frame rails are really thin. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted March 18, 2014 Author Share Posted March 18, 2014 The rails have lots of lateral support. There are tubes welded from the xmember to the TC rod brackets and from there to the rockers. For vertical support there is a large brace right under the motor mount bracket. The motor mount will hit about 5" behind the brake bulkhead fitting right on top of the triangular brace for the TC rod. Between shortening the upper rail, adding the brace to the lower at the STB, adding the xbrace at that position, the K member and brace to the rocker, the rocker to the upper frame, and the two cage tubes that attach to the bottom of the A pillar and the dash bar to the STB, I think I'll be alright, and I would guess that it will be a heck of a lot stiffer than stock. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted April 5, 2014 Author Share Posted April 5, 2014 Got the driver's side done, not sure I'm happy with the way it came out. I lowered the engine and the tube to the frame rail is pretty flat. 8 degrees is the angle there. Seems to me that more angle is better. Went to do the other side and it's even worse. 4 degrees. Not sure what to do now. Looked again at Mike Kelly's mounts, and they've got a bolt extended in single shear. Not ideal. Mine has a bolt in single shear too, but there are very few threads extended. Still thinking about alternatives. I made a new plate for the pass side and extended it up an inch and that didn't seem to help a whole lot. Made the mount shorter and the angle went from 4 to 20 degrees. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted April 6, 2014 Author Share Posted April 6, 2014 Had a better idea at 3:30AM this morning. Will run something similar to the Dingo mounts that Mikelly has, except I'll run the same bushing I had previously used on the frame and there will be a bolt on clevis so that it's in double shear. Might even try to run a brace up to the STB if I'm feeling wacky. We'll see... Quote Link to comment Share on other sites More sharing options...
JMortensen Posted April 25, 2014 Author Share Posted April 25, 2014 New design. I'm going to run a brace from the top of the box to the strut tower too. After I got it in there I realized how easy it would be. One side down... Quote Link to comment Share on other sites More sharing options...
Six_Shooter Posted April 26, 2014 Share Posted April 26, 2014 I had some replies quoted and such, that would have helped illustrate a better solution, but you have changed designs, for the better, mostly. I think you were justified in being concerned. You had 2 pivot points on that mount essentially, the bushing end, which is an obvious pivot, and then the single bolt on the frame rail becomes another pivot point (on two axis) and believe would have failed with time. You could have stayed with that same idea, by adding to the frame side mount and having it wrap around the frame rail, with another tie in point, to reduce the possibility (or eliminate) the frame side pivot point. This would have been more of a kludge than a solution, to keep the original idea going, but it would have worked. Another issue I see with that original design is drivetrain thrust (I think there's a better name for it but can't think of it right now, final exams and projects has my head all sorts of messed up lol), because you have (had) a single point on the frame rail the mount can spin about that axis, and with the other end being compliant, this would happen for sure, if not right away, it would over time. You would need to put some sort of limiting brace that will keep the drivetrain from moving forward under acceleration. The way you are going now is infinitely better. The only change I would make is to rotate the bushing 90*. You can make a simple U shaped mount that would bolt into the frame rail if you so desired. The reason I would do this is because of the twisting forces and again the drivetrain thrust. The engine as you have the bushings now is not really being supported by a cushioned mount, well there will be that little lip on the end of the bushing, but I'm not sure it will take these kind of loads. With the bushing turned 90* the engine weight, twisting forces and shock from driving over a road or track surface are being absorbed by the bushing then. Not many people realize that engine mounts not only isolate engine vibration from the rest of the car, but also isolate the chassis from the engine by absorbing shock and vibrations from the chassis. I like the new mounts a lot more than the original idea. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted April 26, 2014 Author Share Posted April 26, 2014 Thanks for the input. I would have put the mount the other way and I agree that would have been better, but the issue is that I have tubes welded from the dash bar to the strut towers. There just isn't enough room to lift the engine very far before it hits those tubes, and I didn't want to paint myself into a corner and make it really hard to get the motor in and out. Quote Link to comment Share on other sites More sharing options...
Six_Shooter Posted April 26, 2014 Share Posted April 26, 2014 Fair enough. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted May 25, 2014 Author Share Posted May 25, 2014 (edited) Made the braces from the bushing box to the STB mount today. Also notched the frame rail for steering shaft clearance. There was about 1/8" clearance before. Edited May 25, 2014 by JMortensen Quote Link to comment Share on other sites More sharing options...
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