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TH400 Conversion

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Old May 30, 2009 | 09:26 PM
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Default TH400 Conversion

Hey guys I decided im going to go the TH400 route. I tried searching for some info on here but didn't come up with anything. What ALL would I need for a TH400 conversion in my 2002 F-Body. I have the following suspension mods under the car.

BMR Short Drag Torque arm
BMR Adjustable LCA's
BMR Sub frames
BMR Panhard bar
Rear QA1 Coil overs

My wifes sibling has a TH400 and said I could have it for nothing. So I was going to put it in assuming that it would be better, because all the car really see's is the track. Thanks for the info.
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Old May 31, 2009 | 09:12 AM
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Hey Jessie, you're going to need the following:

TH400
Shifter if RVMB
SFI Flexplate
Converter with LS1 pilot or SBC converter with flexplate adapter
BMR or Yank crossmember
Cusom length driveshaft
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Old May 31, 2009 | 01:59 PM
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Do you have to bang out the trans tunnel?
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Old May 31, 2009 | 02:07 PM
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no you dont. I just did the th350 swap and its really easy.
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Old May 31, 2009 | 03:25 PM
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no banging on trans tunnel is required.
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Old May 31, 2009 | 03:46 PM
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Originally Posted by tee-boy
no banging on trans tunnel is required.
Unless you run a drum shield, then you need to beat the **** out of it. I'm sticking with the blanket so I don't have to reshape my tunnel.
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Old May 31, 2009 | 05:41 PM
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Originally Posted by Reboot
Hey Jessie, you're going to need the following:

TH400
Shifter if RVMB
SFI Flexplate
Converter with LS1 pilot or SBC converter with flexplate adapter
BMR or Yank crossmember
Cusom length driveshaft
does the length of the custom shaft depend on the tail of the tranny? I'm doing the swap from T56 to Th400, more work than 4L60 to th400 obviously
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Old Jun 1, 2009 | 06:48 PM
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Originally Posted by Reboot
Hey Jessie, you're going to need the following:

TH400
Shifter if RVMB
SFI Flexplate
Converter with LS1 pilot or SBC converter with flexplate adapter
BMR or Yank crossmember
Cusom length driveshaft
Don I know yov've looked into this yourself. What route were you going to go on the parts? You have any part numbers when I can compile a list and cost? Let me know what you've come up with. I would by your setup but can't do your asking price at the moment lol.
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Old Jun 1, 2009 | 07:48 PM
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TQ Converter for turbo shaft with LS1 pilot - $800-$1000 or more
Yank Cross member - $ 175
RVMB Shifter- $ 200
Custom Drive Shaft - $300-$450
TCI Flexplate - $200
ARP flexplate bolts - $ 25
Fluid, lines, and misc. - $100



So, if the free tranny is RVMB you are looking at around $1700 for new stuff and $1500 if you can reuse your stock shifter. You may find some deals in the for sale section to save you a few bucks.

Can you provide info on the 400?
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Old Jun 2, 2009 | 12:49 PM
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You will need

- th400 crossmember (should be the same as a m6 I got mine from Midwest chassis)
- on the 4" tailshaft (the smaller size I think thats the correct measurement) a different driveshaft since the driveshaft input is larger which I also got from Midwest chassis
- Get the better flexplate but its not needed

- I use the stock shifter on my RMVB so it is not needed, just fab up a way to bolt it to the pan

- I have an ultra bell on mine and I did not need to beat out the tunnel

- You will need a different way to mount your torque arm since there is not a stock bracket on your th400 trans. I use a short tunnel mount torque arm

- You will need new Gr 8 bolts. They don't have to be arp by any means

- You will need a torque converter, but look into it because I don't think you need anything to special. Just talk to your converter maker on it.

- I used an aftermarket cooler and ran some lines to it and it works perfect. The th400 has a larger pipe tread fitting than the th350 and 4l60e.

I could be missing somethings also but it doesn't take that much to install a th400.
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