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lower subframe bushings

Old 06-09-10, 02:25 AM
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lower subframe bushings

I have a 2nd gen t2, I made some subframe and diff bushings for my car out of delrin. I tried to make them as close to factory height levels. I forgot the measurement of the distance between the subframe and the body of the car, but I was thinking of shortening that.

I'm thinking I could keep a lower ride height for the rear without sacrificing as much control arm angle. Of course I was also thinking of making my engine and trans mounts shorter too so I get minimum driveshaft angle. Other plumbing might be shifted a tad, but nothing major, probably less than 1/2 inch, 13mm.

What do you guys think?
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Old 06-09-10, 03:33 PM
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the E30 bmw people like to raise the subframe, as the geometry sucks on that car, and its non adjustable from the factory.

on the FC it would still help, although the camber and toe curves are better, and more adjustable, so its not needed as badly
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Old 06-09-10, 05:09 PM
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The engine and trans are on top of their mounts, so you would actually have to make those thicker to raise the engine and trans relative to the frame.

Doing this would raise the center of gravity vs the frame of the car though.

You could experiment with the angle the diff is mounted at, though with solid diff mounts in the rear there won't be much play in the angle.
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Old 06-10-10, 03:12 AM
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I'm confused here. Do I have it wrong?

I was thinking that when people lower their cars the angle of the rear suspension arms gets real negative. I was thinking if I left less space between the subframe and body of the car, it would lower the body of the vehicle without sacrificing the the rear trailing arm movement.

And since the front subframe has no bushings, the engine would need to be lowered for the proper driveshaft angle. Do I have this backwards????
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Old 06-10-10, 07:52 AM
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The driveshaft angle isn't about the drive shaft itself. You need the pinion and the output shaft parallel. If you end up raising the front of the diff, you need to lower the back of the tranny.
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Old 06-10-10, 11:57 AM
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since the FC has the subframe and diff mounted separate, i wonder if you could raise the subframe the 10-15mm and just modify the front diff mount so the diff stays in the same place
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Old 06-11-10, 01:35 AM
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Good point. The front diff bushings would need to be adjustable.

Oh yeah, I was thinking about it and if I made the gap betweent he subframe and body of the car, the engine and tranny mounts would need to be raised a bit. :/

j9fd3s, not a bad idea, but I'm thinking the front diff bushing would have a bad preload
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Old 06-11-10, 12:05 PM
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Originally Posted by initial D is REAL! View Post
Good point. The front diff bushings would need to be adjustable.

Oh yeah, I was thinking about it and if I made the gap betweent he subframe and body of the car, the engine and tranny mounts would need to be raised a bit. :/

j9fd3s, not a bad idea, but I'm thinking the front diff bushing would have a bad preload
yeah you'd have to custom make a diff mount, or something
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Old 06-11-10, 03:58 PM
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Originally Posted by j9fd3s View Post
since the FC has the subframe and diff mounted separate, i wonder if you could raise the subframe the 10-15mm and just modify the front diff mount so the diff stays in the same place
One potential issue is if you change the relationship between the suspension and the diff too much you might over-angle the cv joints. I doubt that will be an issue though I don't think it will change the relationship any more than lowering the car with springs by the same amount would do.
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