Which auto trans hemi swap?

Author Topic: Which auto trans hemi swap?  (Read 3316 times)

Offline glovemeister

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Which auto trans hemi swap?
« on: September 02, 2014 - 02:40:42 AM »
Looking at doing a hemi swap on my 71 chally.

From my research it appears that the 2wd truck, 545re is the trans to use, because of no difficult speed sensors etc.
However, since I will be buying a complete car like a 2007 magnum, charget etc. I would prefer to use the trans it has with it. With these car transmissions it is my understanding that I need the various modules for the trans to work.

In essence I know the car with have a hemi with auto trans, and I will be buying a complete car and swapping everything I can into mine.

I am potentially interested in swapping the challenger upper body onto the lx lower frame. This would provide advantages in that I can use all factory dodge equipment, including trans, irs (front rear) etc and not have issues with speed sensors.

My other choice is to buy a complete car, use what I can, sell the transmission and purchase a truck variant, install 4 link in rear, with alterkation front.

Mainly looking for advice on the trans issue and which one I should start the build with.


Thanks
1971 Challenger RT




Offline dfrazz

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Re: Which auto trans hemi swap?
« Reply #1 on: September 02, 2014 - 08:29:56 AM »
I have a NAG1 for sale if you end up going that route.

Offline glovemeister

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Re: Which auto trans hemi swap?
« Reply #2 on: September 02, 2014 - 02:38:48 PM »
Yeah I've heard the NAG1 is an option. If I recall correctly it is the one that needs all the sensors. In this stage of the project I am in for all options and just doing planning since I haven't committed one way or the other.

1971 Challenger RT

Offline thedodgeboys

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Re: Which auto trans hemi swap?
« Reply #3 on: September 05, 2014 - 05:38:31 PM »
A small block 727 or a 904 will also work behind gen III hemi.  :2cents:
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Offline Chryco Psycho

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Re: Which auto trans hemi swap?
« Reply #4 on: September 05, 2014 - 11:57:58 PM »
from some of the reading I have been doing it looks like it may be just as easy to buy an Lx Chall wrecked & hang old sheet metal on the chassis rather than trying to fit an LX platform into an older body

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Offline Modern Muscle

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Re: Which auto trans hemi swap?
« Reply #5 on: September 09, 2014 - 09:56:22 AM »
We are currently working on a Plug and play stand alone system for the NAG1  should have more info to share soon

Offline Lotsapins

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Re: Which auto trans hemi swap?
« Reply #6 on: September 12, 2014 - 11:00:21 AM »
The NAG1 is by far the best way to go. There are many reasons why but most have to do with the way they are geared. Try driving a new charger with a HEMI and see what its like to have low end torque and top end highway. If you use the 545 you won't have any low end unless you go with a tall rear end gear, but then you loose top end cruising. The modules are a pain, but the end result is better. If Modern muscle gets the stand alone controller working, that also will be good. Problem is they been at it for a long time, so who knows when it will be ready.
Thanks , Keith
71 Challenger Conv
Build Thread: http://www.cuda-challenger.com/cc/index.php?topic=97569.0
71' Roadrunner Stock restored 383 4spd
08 Charger SRT8 Super Bee
07 Ram 2500 4WD Cummings

Offline glovemeister

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Re: Which auto trans hemi swap?
« Reply #7 on: September 13, 2014 - 03:56:32 AM »
The NAG1 is by far the best way to go. There are many reasons why but most have to do with the way they are geared. Try driving a new charger with a HEMI and see what its like  to have low end torque and top end highway. If you use the 545 you won't have any low end unless you go with a tall rear end gear, but then you loose top end cruising. The modules are a pain, but the end result is better. If Modern muscle gets the stand alone controller working, that also will be good. Problem is they been at it for a long time, so who knows when it will be ready.

Yeah I think I am going that way. I assume you have done the NAG1 some how?

I think its cool modern is trying to bring it to market, and I'm sure its an arduous process. But over the years I've seen a lot of flash in the pan stuff and products that don't materialize. So I'm not gonna count on that until its ready.
1971 Challenger RT

Offline Lotsapins

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Re: Which auto trans hemi swap?
« Reply #8 on: September 14, 2014 - 11:37:04 AM »
I got all the info and complete harness from Hotwire. Chris is very knowledgeable and has several cars on the road with his Hemi/NAG1 harness. Although my car isn't done yet, this trans setup is the best automatic option out there. Keep in mind the cars they came out have 308 rear end gears. They have great performance out of the hole and also great top end cruising. I'm doing mine with a 323 posi 8 3/4. I already have a stock restored muscle car with a stick (71 RoadRunner 383 4spd) and I want this Convert Chall for more cruising and driving comfort.
Thanks , Keith
71 Challenger Conv
Build Thread: http://www.cuda-challenger.com/cc/index.php?topic=97569.0
71' Roadrunner Stock restored 383 4spd
08 Charger SRT8 Super Bee
07 Ram 2500 4WD Cummings