5.7 to 6.4 swap

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Takemehomewv

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i was looking into swapping with the hellcat engine but thats 25gs. Now im looking at the 6.4 hemi which is around 9gs. Also looking at putting a supercharger on it (magnuson tvs2300). how difficult would the swap be? could the 8hp70 8 speed tranny handle the hp. Any input would be awesome
 

6.7CumminsDrvr

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I’m sure the experts will chime in or point you to some other resources but are you talking about the 6.4 truck engine or SRT? Reason I ask is I thought the 6.4 SRT didn’t like anything other than low boost or you run into problems.
 

IRSmart

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Skip the swap, there’s not a huge difference in the two engines as far as power. Internals and the ability to hold a supercharger, I’ll let someone else jump in there.
 

Ohio5pt7

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I vote forge the 5.7 and put the blower on it . Will hold a lot more power than a stock 6.4 cheaper and no swap headaches.

Sent from my SAMSUNG-SM-G891A using Tapatalk all grammar errors brought you by fat fingers and auto correct.
 

Booms

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^ All these...

MMX drop in forged internals and slam a Whipple on it.

And get a REPUTABLE tuner.

You're welcome. :)
 

Sandevino

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Anytime you swap an engine into an older model, you've got to have deep pockets for the unexpected. I'm not saying it isn't possible as many have done it before but he price tags vary.

Engine Info

There are differences with the Hellcat and the Ram 2500/3500 engine which equate to intake, rotating assembly, tuning and HP/TQ numbers at specific RPM for the specific application. Let me explain...

The Hellcat 392 is built to propel a relatively light CAR and essential haul ass. Flat out haul ass... and it does so very nicely. It produces 707 HP at 6800 RPM and 650 TQ at 4800 RPM.

The Ram 2500/3500 392 is built to propel a relatively heavy TRUCK and haul anything and everything attached to it's ass. And it hauls very nicely. It produces 410 HP at 4000 RPM and 429 TQ 4000 RPM.

Torque gets you moving and Horsepower keeps you moving. The RPM / TQ numbers for both engines are spec'd for the specific application.

Transmission Info

8HP70 - it taps out at 516 ft. lb. engine torque per ZF's spec sheet. The Hellcat engine will destroy this transmission very nicely. Could it be built to handle more, maybe, would I find out how much more, nope.

8HP75 - The ZF 8HP75 tops out at 750 ft. lb. engine torque per ZF's spec sheet. In my opinion, you should get this transmission to give yourself some breathing room.

8HP90 / 8HP95 - Full disclosure, these can handle 900 ft. lb. and are the ones I would go for if I were taking on this project.
 

savage_46

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6.4 swapped
If it were me, I'd drop in the forged parts while the engine is still out. Saves time, labor, hassle, double dipping on parts. IIRC, both versions of the 6.4 already have a forged crank.
 

Wild one

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Anytime you swap an engine into an older model, you've got to have deep pockets for the unexpected. I'm not saying it isn't possible as many have done it before but he price tags vary.

Engine Info

There are differences with the Hellcat and the Ram 2500/3500 engine which equate to intake, rotating assembly, tuning and HP/TQ numbers at specific RPM for the specific application. Let me explain...

The Hellcat 392 is built to propel a relatively light CAR and essential haul ass. Flat out haul ass... and it does so very nicely. It produces 707 HP at 6800 RPM and 650 TQ at 4800 RPM.

The Ram 2500/3500 392 is built to propel a relatively heavy TRUCK and haul anything and everything attached to it's ass. And it hauls very nicely. It produces 410 HP at 4000 RPM and 429 TQ 4000 RPM.

Torque gets you moving and Horsepower keeps you moving. The RPM / TQ numbers for both engines are spec'd for the specific application.

Transmission Info

8HP70 - it taps out at 516 ft. lb. engine torque per ZF's spec sheet. The Hellcat engine will destroy this transmission very nicely. Could it be built to handle more, maybe, would I find out how much more, nope.

8HP75 - The ZF 8HP75 tops out at 750 ft. lb. engine torque per ZF's spec sheet. In my opinion, you should get this transmission to give yourself some breathing room.

8HP90 / 8HP95 - Full disclosure, these can handle 900 ft. lb. and are the ones I would go for if I were taking on this project.

Not quite right. The last 2 numbers of the ZF designation stand for Newton Meters not lb-ft. The HP75 is good for roughly 563 lb-ft , the HP90 is good for 663 lb-ft and the HP 95 which is only available in the TrackHawks is good for roughly 700 lb-ft.Those are continuous ratings though,they'll take more then that for short periods of time. Matt Fikac is putting down over 1100 rwhp through a built 8HP70 ,they can be built to take some serious abuse,but they aren't cheap. Paramount / Hellraisier are places to look at for built ZF trannies. Supposedly Charles Barret at Hellraiser is putting the 8HP95 and AWD transfer case out of a Track Hawk into a late model 1500,and he has successfully swapped the 8 speed into the older 5/6 speed trucks
 

Wild one

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i was looking into swapping with the hellcat engine but thats 25gs. Now im looking at the 6.4 hemi which is around 9gs. Also looking at putting a supercharger on it (magnuson tvs2300). how difficult would the swap be? could the 8hp70 8 speed tranny handle the hp. Any input would be awesome

Why not start with a forged stroker 6.4. This is MMX's offerings,but there's lots of other outfits who offer a forged 6.4 stroker.
https://www.modernmusclextreme.com/c-192-64l-hemi-based-stroker-engines.aspx
 

Sandevino

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Not quite right. The last 2 numbers of the ZF designation stand for Newton Meters not lb-ft. The HP75 is good for roughly 563 lb-ft , the HP90 is good for 663 lb-ft and the HP 95 which is only available in the TrackHawks is good for roughly 700 lb-ft.Those are continuous ratings though,they'll take more then that for short periods of time. Matt Fikac is putting down over 1100 rwhp through a built 8HP70 ,they can be built to take some serious abuse,but they aren't cheap. Paramount / Hellraisier are places to look at for built ZF trannies. Supposedly Charles Barret at Hellraiser is putting the 8HP95 and AWD transfer case out of a Track Hawk into a late model 1500,and he has successfully swapped the 8 speed into the older 5/6 speed trucks

Thanks. I converted the wrong way.
 

68PowerWagon

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It's not like the old days where all you had to worry about was the motor mounts & the bell housing. I personally don't think the juice is worth the squeeze.
 

Sandevino

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It's not like the old days where all you had to worry about was the motor mounts & the bell housing. I personally don't think the juice is worth the squeeze.

Agreed, but to some it's a challenge.
 

audiophile

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Anytime you swap an engine into an older model, you've got to have deep pockets for the unexpected. I'm not saying it isn't possible as many have done it before but he price tags vary.

Engine Info

There are differences with the Hellcat and the Ram 2500/3500 engine which equate to intake, rotating assembly, tuning and HP/TQ numbers at specific RPM for the specific application. Let me explain...

The Hellcat 392 is built to propel a relatively light CAR and essential haul ass. Flat out haul ass... and it does so very nicely. It produces 707 HP at 6800 RPM and 650 TQ at 4800 RPM.

The Ram 2500/3500 392 is built to propel a relatively heavy TRUCK and haul anything and everything attached to it's ass. And it hauls very nicely. It produces 410 HP at 4000 RPM and 429 TQ 4000 RPM.

Torque gets you moving and Horsepower keeps you moving. The RPM / TQ numbers for both engines are spec'd for the specific application.

Transmission Info

8HP70 - it taps out at 516 ft. lb. engine torque per ZF's spec sheet. The Hellcat engine will destroy this transmission very nicely. Could it be built to handle more, maybe, would I find out how much more, nope.

8HP75 - The ZF 8HP75 tops out at 750 ft. lb. engine torque per ZF's spec sheet. In my opinion, you should get this transmission to give yourself some breathing room.

8HP90 / 8HP95 - Full disclosure, these can handle 900 ft. lb. and are the ones I would go for if I were taking on this project.
The trucks use the 6.4l (392ci) this is the same engine the Scat Packs etc use. The Hellcat engine is a 6.2l (378ci) also used in the Trackhawk and Demon.


Sent from my SM-G955U using Tapatalk
 

audiophile

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i was looking into swapping with the hellcat engine but thats 25gs. Now im looking at the 6.4 hemi which is around 9gs. Also looking at putting a supercharger on it (magnuson tvs2300). how difficult would the swap be? could the 8hp70 8 speed tranny handle the hp. Any input would be awesome
25k, might as well spend a couple more and grab a Hellaphant.........

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Wild one

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The trucks use the 6.4l (392ci) this is the same engine the Scat Packs etc use. The Hellcat engine is a 6.2l (378ci) also used in the Trackhawk and Demon.


Sent from my SM-G955U using Tapatalk

Prior to 2017 the Scatpack 6.4's didn't use the BGE block. The BGE block was originally cast for the HD trucks 6.4,then repurprosed for the Hellcats/Demons/Trackhawks 6.2's. After 2017 all 6.4's use the big gas engine (BGE) block
 

IRSmart

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The trucks use the 6.4l (392ci) this is the same engine the Scat Packs etc use. The Hellcat engine is a 6.2l (378ci) also used in the Trackhawk and Demon.


Sent from my SM-G955U using Tapatalk
The 6.4 in the trucks and in the SRT cars is not the same.
 

NH RAM

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There's a user on another forum similar to this one that has done this swap. Google it, the thread should pop up and you'll learn all about the swap.
 

Socalramfan

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Anytime you swap an engine into an older model, you've got to have deep pockets for the unexpected. I'm not saying it isn't possible as many have done it before but he price tags vary.

Engine Info

There are differences with the Hellcat and the Ram 2500/3500 engine which equate to intake, rotating assembly, tuning and HP/TQ numbers at specific RPM for the specific application. Let me explain...

The Hellcat 392 is built to propel a relatively light CAR and essential haul ass. Flat out haul ass... and it does so very nicely. It produces 707 HP at 6800 RPM and 650 TQ at 4800 RPM.

The Ram 2500/3500 392 is built to propel a relatively heavy TRUCK and haul anything and everything attached to it's ass. And it hauls very nicely. It produces 410 HP at 4000 RPM and 429 TQ 4000 RPM.

Torque gets you moving and Horsepower keeps you moving. The RPM / TQ numbers for both engines are spec'd for the specific application.

Transmission Info

8HP70 - it taps out at 516 ft. lb. engine torque per ZF's spec sheet. The Hellcat engine will destroy this transmission very nicely. Could it be built to handle more, maybe, would I find out how much more, nope.

8HP75 - The ZF 8HP75 tops out at 750 ft. lb. engine torque per ZF's spec sheet. In my opinion, you should get this transmission to give yourself some breathing room.

8HP90 / 8HP95 - Full disclosure, these can handle 900 ft. lb. and are the ones I would go for if I were taking on this project.



Very nice write-up and explanation :waytogo:

Now if there was only a way to get the 4.7 power/torgue up :flamingdevil:
 
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