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Old Feb 13, 2007 | 10:33 PM
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Default Motor Mount Help

I need some help with my motor mounts. My truck has a mustang II front suspension with sbc mounts and I made a set of S&P style adapter plates out of 1/4" steel. For some reason the holes won't line up. I can get a bolt in one side, but the other side doesn't fit. I have added 3/16" shims to each side but still no luck. Does anybody have any ideas?

Thanks,
Brian

52 Chevy truck with 98 LS1 and 4l60e
Attached Thumbnails Motor Mount Help-p1000423-1.jpg  
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Old Feb 13, 2007 | 10:45 PM
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There are two SBC type of Motor mounts..

1) Short and Wide, which has a Inside Width- 2 5/8" and Height Base to Bolt Center- 1 3/4"

2) Tall and Narrow, Inside Width- 2 3/8" Height Base to Bolt Center- 2 3/16"

Question, what is the width of the frame mount. There is about 1/4" different between the two mount in width and 7/16" in height.

maybe you have the wrong mounts for your mustang II setup ?

Good luck..
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Old Feb 14, 2007 | 09:32 PM
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It looks like I have the short and wide mounts. They should be the correct mounts for my suspension because I bought with my suspension kit.

The width between the frame mounts is 16 7/8".

Does anyone else have a suggestion? This is getting frustrating.

Thanks,
Brian
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Old Feb 14, 2007 | 09:51 PM
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Who fab'd up the engines Frame mounts.. is it possible that they didn't fab them up correctly ? From the pic, it looks like the mount is hitting the frame mount, is that the case ?

What happens when you take out all of the shims and spacers ?
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Old Feb 14, 2007 | 10:10 PM
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If it is hitting the mount, you might just need to switch to Energy Suspension mounts. And possibly ATS style plates that flip the mount upside down.
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Old Feb 15, 2007 | 08:46 AM
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Question Truck Frame

Could the truck frame be slightly out of square or tweeked?
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Old Feb 15, 2007 | 12:54 PM
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The frame mounts were part of the mustang II setup. They bolt to the crossmember, and all the holes are pre-drilled. All the holes lined up, so I don't think that is the problem. I bought the mounts that bolt to the block from the same place. The guy told me they were the right ones for my setup.

If I remove the shims, the holes are a little further off. I suppose I could keep adding shims until it lines up, but I don't want 1" thick adapter plates on each side.

The driver's side framerail was bent slightly upward just in front of the cab when I bought it. I had it repaired, but it's I doubt it's perfect. Would a small tweek in the frame throw it off that much?
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Old Feb 15, 2007 | 01:07 PM
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It could... did the subframe mesaure turn sq and level ? I would call the manufactor of the subframe and talk to them about your problem... maybe they can send you a new frame mount or setup...?
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Old Feb 15, 2007 | 08:51 PM
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Well, I took another look tonight, and I think I can flip the mounts upside down like the ATS mounts and make it fit. I will still need the shims, but at this point I can live with that.

I will test it this weekend and give an update afterwards. If it works, I will probably make another set of adapter plates out of 1/2" material to clean things up and get rid of all the shims.

Thanks again for all the advice. I'm sure I will need a lot more when it's time to finally fire it up.
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