Hemi 6.4L 475hp swaps - where is the data?

outatime7

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When I scour Instagram, it seems like AMW 4x4, DCD customs, and a few other shops are cranking out 6.4L Hemi swaps for the JL, yet I can't seem to find a single before and after, or otherwise comparison video showing how fast these things can put down the 0-60, quartermile, etc. compared with stock. How is this possible?



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Kevin Mojito

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I cant speak for JL hemi swap, but can for TJ Hemi.
It's not fast. Yes, it is faster then the 6 that was there before. It's about the torque. The V-8 torque just makes these Jeeps jump. At any speed they move out with a tap of the throttle. You don't need to floor board it to move. I live in hilly country, my JL ( 3.6 auto ) shifts from 8th to 5th climbing hills, the TJ just stays in overdrive and keeps pulling at 1800 rpms.
 

rubileon

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When I scour Instagram, it seems like AMW 4x4, DCD customs, and a few other shops are cranking out 6.4L Hemi swaps for the JL, yet I can't seem to find a single before and after, or otherwise comparison video showing how fast these things can put down the 0-60, quartermile, etc. compared with stock. How is this possible?
Not saying there's no benefit to putting on a 6.4 but if you're after everyday performance, they can't beat a supercharged 3.6 because of the power to weight ratio.

The 6.4 swap will have better dyno numbers but it'll also be close to 450 lbs (200 kgs) heavier which affects acceleration, corner handling, braking, etc. none of which are compromised when you put a supercharger on.

If you're going to spend at least 40+ grand fully build everything (transmission, axles, brakes, etc.) for a proper engine swap that will make you feel like you did an upgrade over what a supercharger can give, look for an engine that can make at least 800 hp at the crank.
 

oceanblue2019

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Not saying there's no benefit to putting on a 6.4 but if you're after everyday performance, they can't beat a supercharged 3.6 because of the power to weight ratio.

The 6.4 swap will have better dyno numbers but it'll also be close to 450 lbs (200 kgs) heavier which affects acceleration, corner handling, braking, etc. none of which are compromised when you put a supercharger on.

If you're going to spend at least 40+ grand fully build everything (transmission, axles, brakes, etc.) for a proper engine swap that will make you feel like you did an upgrade over what a supercharger can give, look for an engine that can make at least 800 hp at the crank.
To get Hemi level power you'd need to be running 14psi (or more) of boost and no way that is happening with the factory compression ratio.

I've been lucky enough to drive a Gladiator with a 6.4L 475hp Hemi and it was absolutely fantastic. One day I will do the same for my JLUR.
 

rubileon

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To get Hemi level power you'd need to be running 14psi (or more) of boost and no way that is happening with the factory compression ratio.

I've been lucky enough to drive a Gladiator with a 6.4L 475hp Hemi and it was absolutely fantastic. One day I will do the same for my JLUR.
I did say a 6.4 will have better dyno numbers.
 

Kevin Mojito

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but it'll also be close to 450 lbs (200 kgs) heavier
I think it's more like 150-185 lbs more than the 3.6. It was only 60-80 lbs more than my 4.0 swap in the TJ. Either way I would take a Hemi over the v6 any day of the week.
 

                           


































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