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Moving rear subframe back one inch

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Old Sep 18, 2016 | 12:04 PM
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Default Moving rear subframe back one inch

I want to move the rear subframe back one inch to help with high speed stability and to clear a 26 inch tire. I am curious if anyone else has done this. Just looking for input before I dive in.
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Old Sep 18, 2016 | 01:01 PM
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Seems like an awful amount of work and expense for something that you will probably not be happy with.

I would stay with a little smaller tire
Old Sep 18, 2016 | 01:03 PM
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I don't think it would be that much work, its all of 6 bolts holding the subframe in. The coilovers have pillow ***** up top so I shouldn't have to move the shock towers.
Old Sep 18, 2016 | 01:29 PM
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What will a special longer drive shaft cost?
Old Sep 18, 2016 | 01:45 PM
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I'll just make a one inch spacer to go between the driveshaft and diff
Old Sep 18, 2016 | 01:58 PM
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You'll need to do something about the front-to-rear brake hard line, and I'm not sure if there's an extra inch in the parking brake cable. You might also see some tire rubbing from moving the tire that far backwards.

--Ian
Old Sep 18, 2016 | 02:14 PM
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Brake line will be easy enough, that's just cut, flare, and splice in what I need. I think I have enough adjustment for the parking brake cable. I'll measure to make sure it's one inch, I can just center the wheel in the wheel well and be good.
Old Sep 18, 2016 | 02:25 PM
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Oh boy.
Old Sep 18, 2016 | 03:02 PM
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Another reason to move the frame back is NHRA rules, it is against the rules to have a swapped car with a wheel base less than 90 inches. I don't want to get hit with something silly like that.
Old Sep 18, 2016 | 05:05 PM
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I have contemplated doing the same thing to clear a big tire. There is an awful lot of work involved, but it would make a better drag car if you can pull it off.
Old Sep 18, 2016 | 05:15 PM
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Originally Posted by themetalman
I want to move the rear subframe back one inch to help with high speed stability and to clear a 26 inch tire. I am curious if anyone else has done this. Just looking for input before I dive in.
I have never seen or heard of anyone doing this. Good luck, I'm interested to see what is involved to pull it off.
Old Sep 18, 2016 | 05:41 PM
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Ive already have hundreds, if not thousands of hours into this car, once winter hits I will probably tackle it.
Old Sep 18, 2016 | 06:31 PM
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Tell us more about it.
Old Sep 18, 2016 | 06:37 PM
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The car? It is a LS swap. Has a LS6 with a nice cam, T56 from a Fbody, 8.8 rear from a 04 cobra. Here is a before and after of the car, we pretty much gutted the entire car and built it back up.


Old Sep 18, 2016 | 06:44 PM
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Me likey!
Old Sep 19, 2016 | 02:26 PM
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Nice! At thhis point though, why not build a custom rear suspension for drag racing if that is what you are doing with it?
Old Sep 19, 2016 | 03:09 PM
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Take a look at the clearance between the coilover and the axle, I haven't looked in a while but it might be close when you lean the shock forward an inch.
Old Sep 19, 2016 | 03:24 PM
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Awesome car. Have you taken it to the strip yet? Any timeslips as it sits?
Old Sep 22, 2016 | 11:24 PM
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very nice. do you have a build thread somewhere? sorry can't help with the rear sub issue. but perhaps you can mod the sub frame to move the rear diff back a few inches? I would think building some new mounts on the sub-frame might be easier but no idea really. good look with the sick build!
Old Sep 23, 2016 | 07:59 AM
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What's your plan? Move the mounting holes 1" forward and close up the old holes? fwiw- I got a custom drive shaft made from two for $115 at a local 4x4 driveline shop. Not expensive IMO.



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