6.4 Hemi into 1974 challenger

Harry Williams

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I want to put a 6.4 into my 74 challenger but dont want to cut the floor up. Is there a transmission option that will work without cutting it up? Auto perfered but stick would be great too. All help appreciated Thanks
 

493 Mike

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You may get more response at "for E bodies only".
Mike
 

Nxcoupe

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I want to put a 6.4 into my 74 challenger but dont want to cut the floor up. Is there a transmission option that will work without cutting it up? Auto perfered but stick would be great too. All help appreciated Thanks
Yes, a 727 sb trans would work great. You could also look at other computer controlled transmissions from other manufacturers, as they make adapters. I'd call a big transmission supplier and bounce it off them.
 

Harry Williams

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I wouldn't have thought you could get a 727 hooked up to a 6.4 will see if i can find a adapter.
 

toolmanmike

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Contact Sublime one on FABO. I believe he did that engine swap.
 

Project66

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srw-409

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Here are a couple of threads on e-bodies.org that use the older transmissions:


 

Nxcoupe

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I just put a TKX in my '66 Satellite and I did not have to cut the tunnel. Well, except for the shifter hole, but that was pretty minor.

Silver Sport has an A41 kit that I wish I had known about before I did the TKX swap. I don't have any actual experience with their kit, but it looks like it will give you a modern, 4-speed auto with OD. TREMEC TKX, TREMEC Magnum & SST A41 Conversion Kits for MOPAR E-Body: AAR, Barracuda, Challenger, Cuda, Gran Coupe, R/T, SE and T/A
What brand makes the 'A41'?
 

5.7 hemi

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I did a 6.1 swap with a rebuilt 727 with GV OD for a member here on the forum into his 66’ Belvedere. Rear gears were 3:23’s and he drove it home to the Bay Area and he said he got good fuel mileage.
 

Polara426

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Check out Silver sport transmissions I put there A41 in 6.4 71 Charger very happy.
 

Project66

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Looking at the website, the A41 kit does include a controller. I asked for quote earlier this year while I was waiting for my TKX to ship and it was about $4,500 for everything. That's considerably less than I paid for my TKX kit and it probably would have been a simpler install since I would not have to add a pedal or go through that whole bellhousing alignment debacle.

Note to self: do your research BEFORE you spend your money! I have no regrets. Ultimately, I'll probably be happier with the TKX, but I might have taken the A41 route if I had know about that option.
 

Polara426

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Yes the controller is included by compushift with very good support everything is included with 3 different hp ratings went with the medium trans upgrade and had them build a driveshaft about 5k if there was more support for the 8 speed Chrysler trans at the time I would have gone with that. No tunnel work on a B body put one in a A body with minor tunnel work.
 

392heminut

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I wouldn't have thought you could get a 727 hooked up to a 6.4 will see if i can find a adapter.
You don't need an adapter, just the flexplate. I bolted a 727 to the 5.7 Hemi in my 70 Cuda with no problem at all. I used the flexplate that came off of the 2004 truck that the engine came out of. I just took the flexplate to a machine shop and had the welds cut to remove the starter ring gear from the flexplate. The torque converter bolt pattern is just a hair different, 727 is inch pattern and the 5,7 flexplate is metric pattern. I opened the bolt holes up just a bit with a dremel tool.
 

5.7 hemi

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Buy a flex plate! Cutting and opening up the holes throws the balance off.
 

furious70

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You just need a special flexplate and it bolts right up

You don't need an adapter, just the flexplate. I bolted a 727 to the 5.7 Hemi in my 70 Cuda with no problem at all. I used the flexplate that came off of the 2004 truck that the engine came out of. I just took the flexplate to a machine shop and had the welds cut to remove the starter ring gear from the flexplate. The torque converter bolt pattern is just a hair different, 727 is inch pattern and the 5,7 flexplate is metric pattern. I opened the bolt holes up just a bit with a dremel tool.

Buy a flex plate! Cutting and opening up the holes throws the balance off.

100% agree, there are both SFI and affordable non SFI flexplates available that correctly mate the 2.
 
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