Author Topic: Which swaps in best in a 70 Cuda? 6.1 or 6.4 Hemi?  (Read 5043 times)

Offline Simple

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Which swaps in best in a 70 Cuda? 6.1 or 6.4 Hemi?
« on: September 14, 2015 - 08:12:12 PM »
Considering a Gen III Hemi in my 70 Cuda. Swapping out tranny as well. Is there any differences in fitting a 6:1 vs a 6.4?




Offline GreenFish

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Re: Which swaps in best in a 70 Cuda? 6.1 or 6.4 Hemi?
« Reply #1 on: September 15, 2015 - 11:21:52 AM »
I'm pretty sure its pretty much the same thing. (not that I'm an expert) but if i were in the market, id just buy one of the crate 6.4 engines and put it in.
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Offline dfrazz

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Re: Which swaps in best in a 70 Cuda? 6.1 or 6.4 Hemi?
« Reply #2 on: September 15, 2015 - 02:33:42 PM »
Dropped in a 6.4 in my friends '73.  Easily fits.




Offline GoodysGotaCuda

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Re: Which swaps in best in a 70 Cuda? 6.1 or 6.4 Hemi?
« Reply #3 on: September 15, 2015 - 02:54:43 PM »
Packaging is generally the same between the 5.7, 6.1, 6.4.

Primarily comes down to what you want to spend.
Build Page: Goody's 'Cuda Build Page
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Offline Cudakiller70

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Re: Which swaps in best in a 70 Cuda? 6.1 or 6.4 Hemi?
« Reply #4 on: September 15, 2015 - 04:30:06 PM »
Packaging is generally the same between the 5.7, 6.1, 6.4.

Primarily comes down to what you want to spend.
Are their big dollar differences between the engine sizes and what it takes to put them in? Jim
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Offline GoodysGotaCuda

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Re: Which swaps in best in a 70 Cuda? 6.1 or 6.4 Hemi?
« Reply #5 on: September 15, 2015 - 09:59:59 PM »
Are their big dollar differences between the engine sizes and what it takes to put them in? Jim



Install is pretty much synonymous between them, it is primarily a difference in funding the initial power package. You can get a good rebuild-worthy non-Eagle 5.7L for $900-$1,500. With coils, some accessories, fuel rail, intake, etc. A decent mileage 6.1L will run you around $5,000-$6,000, a new 6.4L will push $8,000 for the long block.

My personal path to success is to start with a basic 5.7L. I can easily make ~320whp with it, the initial cost is much lower and will help me actually get "the swap" accomplished. Once I get things settled, the bugs out of it, the transmission setup..then I can work on a larger engine if I please. However, I can also add a small amount of boost to the 5.7L and run a easy 450-500whp without much trouble. However, going from 240whp [318] to around 320whp and from a 904 to a 6-speed manual..I'll be giddy enough to not notice the "lack" in power. The car should be good for an easy 12-second 1/4 with a double-overdrive and net 20mpg or so on the highway.


It's all in what you want to do. Sure, I'd love to have a 6.4L in my car, however I much rather have a 5.7L than nothing..or an old LA small block. Affording a high-end engine right off the bat would push my project budget too far and it would either never get started, or never get finished.


« Last Edit: September 15, 2015 - 10:05:49 PM by GoodysGotaCuda »
Build Page: Goody's 'Cuda Build Page
1976 Dodge Warlock
1972 Barracuda - 5.7 Hemi + T56 Magnum

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Offline Cudakiller70

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Re: Which swaps in best in a 70 Cuda? 6.1 or 6.4 Hemi?
« Reply #6 on: September 15, 2015 - 11:48:46 PM »
Ok gotcha, it's the same with GM's LS engines. I am new to mopars, but the newer engines have great torque and run so well. I'm sure with some programming and other changes you can get a lot more power with a lot less headaches plus drivability and more. I am sure you can shred some tires with a 5.7. I am in the same ball park and probably would do the 5.7 it's enough power for me I'm trying to keep this car right side up! Jim
Auto spell I'm tired of your shirt
The above is just my opinion
Our Constitution was made only for a moral and religious people. It is wholly inadequate to the government of any other.
John Adams

Offline YellowThumper

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Re: Which swaps in best in a 70 Cuda? 6.1 or 6.4 Hemi?
« Reply #7 on: September 16, 2015 - 05:10:55 PM »
With pic and that statement I see there is no factory K frame there. Will it still clear bottom end with the K and factory steering still there? Engine looks to be dropped down pretty low.

Dropped in a 6.4 in my friends '73.  Easily fits.





« Last Edit: September 16, 2015 - 05:16:25 PM by YellowThumper »
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Offline GoodysGotaCuda

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Re: Which swaps in best in a 70 Cuda? 6.1 or 6.4 Hemi?
« Reply #8 on: September 16, 2015 - 06:09:46 PM »
With pic and that statement I see there is no factory K frame there. Will it still clear bottom end with the K and factory steering still there? Engine looks to be dropped down pretty low.


The engine looks relatively at the same place as my picture above, with a stock K-member and Milodon oil pan..
Build Page: Goody's 'Cuda Build Page
1976 Dodge Warlock
1972 Barracuda - 5.7 Hemi + T56 Magnum

Wheel & Tire Specs:Link