Hemi Swap: Transmission choices for Gen III 392 Hemi

[Hemi1632]

Nice work, congratulations! I hope to see it out on the street next summer! All the bugs should be worked out of my challenger by then, we will have to meet up. I want to see all the work you have done up close!

Definitely! I had it downtown until thanksgiving. I put it away back in the suburbs for winter. Need to get the cutouts on there and wire up the keyless entry, etc. this winter.

I've been concentrating on the 69 cuda the past couple weeks. Converting to EFI with a Holley sniper and debating trying to run E85 instead of race fuel (11.4 compression on the 340)


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Nice, let me know how the sniper works out. I have been thinking about putting one on my fathers 67 Cuda but been waiting for them to make one that can handle 700 hp to the wheels.

[Swamp Donkey]

I have it working well in regular, sport and track mode. Manual shifting works with the challenger shifter. I had to get HP Tuners and change the downshift points for 5th all the way down to 1st to stop the trans from failing and dropping to neutral when stopping fast. Russell from Sound German helped me troubleshoot and get it going.

I have the challenger console, but everything else looks like 1974. Wooden steering wheel included. I used the stand alone Mopar kit with the drive by wire pedal that comes with it. You can adapt to a cable (particalrtly if you need kickdown), but drive by wire was easy enough.

Would you happen to have pictures of the interior of your car with the Challenger console?  Thanks!

[392 Cuda]

[392 Cuda]

[Swamp Donkey]

Looks great.  So many decisions for me to make. 

[cudaragtop]

Well after costing it out and a lengthy conversation with Russell at Sound German Automotive
He is Local to Me
We decided to go switch gears and go with an 8HP70 using SGA's Kit and Paddle Shifter.
Found a Challenger Floor shifter from another member.
He's doing a 6.4 with 8HP70 and had an extra shifter. Might try to fit the shifter to the stock console but think the Challenger console would be the way to go.
So...
Looking for an 8HP70, Local preferred
I could get a complete used 8HP from SGA for $1k when he has one available.

[392 Cuda]

The shifter will fit in the console... the console may not fit over the new tunnel.

[cudaragtop]

Well... No small effort, but my buddy and I completed the 8HP70 swap. Took us about 5 days, lots of cutting, grinding, welding and some fab work.

Still have some bugs to work out with the shift points and an issue with the trans faulting to N. Had to order an HP Tuners (and 4 credits just for the trans) to goof around with the trans settings.

My buddy put together another video of it

Is there a pilot bearing in your G3 crank?
Did you remove it for the 727 and have to replace it for the 8HP70?
Is Mopar PN 53009180AB the correct pilot bearing?

Thanks!

[392 Cuda]

I had to remove it for the 727, but the 8HP70 did not need it - perhaps it is because my TC was from a later model, but the TC stub fit right in there. Would not have for with the bearing (or sleeve).

[cudaragtop]

I had to remove it for the 727, but the 8HP70 did not need it - perhaps it is because my TC was from a later model, but the TC stub fit right in there. Would not have for with the bearing (or sleeve).

Cool! 
I pulled the bearing out too for our 727... Wasn't sure if the HP70 needed one.
Thanks!

[Swamp Donkey]

   I'm glad there are great people to share information with.  I don't think I would be brave enough to do the 8HP90 swap without reading about it here. 

[cudaragtop]

Bushing for Hemi Crank to Automatic

https://www.mymoparparts.com/oem-parts/mopar-crank-shaft-pilot-sleeve-4736283aa?c=az0x

[392 Cuda]

I bought one of those, but it was not necessary. Look at the snub on the TC. Mine was as big as that sleeve. It LLC it is smaller (I'm guessing the NAG1 is) you need the sleeve. I can see if I still have it to send to you if you need it.

[cudaragtop]

Yup, I think there are a few differences out there.
I got a line on an 8HP70 but he's out of town until after the holidays.
When I get it, I'll check the torque converter fit into the 6.1 crank.

This is how I got the 6-spd Bearing out...
First time I ever tried to weld... Harbor Freight Flux Core welder.
Looking into some welding classes at my local community college.
Their tech center is 15 min from where I work.
Going to need to do a lot of welding in order to fit the HP70... Floor/tunnel and cross member fabrication.

Need my welds to be a lot better than this.

[392 Cuda]

You'll have lots of practice...