6.4 or 5.7?

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chubz

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I haven't been on here in like 10 years. After kids, divorce and years of bodywork I should get my duster soon and be ready to take the next step.

I always planned on putting a 5.7l Gen III hemi in my car, but it seems that the 6.4 seems to be whats taking over now. What seems to be the consensus? I am looking to run AC and Power steering as well as a 6 speed manual. I would love to be in the 500hp club but drive-ability is more important.

The plan is reading up as much as I can but any quick help would be appreciated.

Lastly what is the best transmission for the 5.7 or 6.4?

20180131_115622.jpg
 
5.7's are cheaper than 6.4.
Stock HP though as you know, is well shy of your goal, so youll be into mods on the little wonder work horse. bolt ons alone (headers, intake, etc) will not get you there. Youll need long tubes, cam, engine/head work, tune - if running oem PCMs, etc.
6.4 is already 485hp, minor bolt ons will put you nicely past 500. It takes more to make the same % of power from a 5.7 than a 6.4 thus the trend towards going that route out the gate. With hellcat conversions being all the rage, 375hp seems sorta pathetic now days.
If your building up a 5.7 or slightly hopping a 6.4, (again, to meet your stated goal) all the rest (cooling, elect power needs, driveline, fab work, etc all would all similarly fall in line nearly the same. ie: same work & money eitherway you go...so little to be gained there on the back end, by going with the 5.7 once the initial engine is purchased. imho.
6.4's though do have their weaknesses (thus thier nickname said in hush tones) but also have a solid rep for building great power & tq. within thier design limit.
so I guess it all depends on whats important, how much "turn key" do you want (no such thing here, but you get the idea I hope) and how much $$ is in your wallet, you can get there with either engine. best of luck.
 
5.7's are cheaper than 6.4.
Stock HP though as you know, is well shy of your goal, so youll be into mods on the little wonder work horse. bolt ons alone (headers, intake, etc) will not get you there. Youll need long tubes, cam, engine/head work, tune - if running oem PCMs, etc.
6.4 is already 485hp, minor bolt ons will put you nicely past 500. It takes more to make the same % of power from a 5.7 than a 6.4 thus the trend towards going that route out the gate. With hellcat conversions being all the rage, 375hp seems sorta pathetic now days.
If your building up a 5.7 or slightly hopping a 6.4, (again, to meet your stated goal) all the rest (cooling, elect power needs, driveline, fab work, etc all would all similarly fall in line nearly the same. ie: same work & money eitherway you go...so little to be gained there on the back end, by going with the 5.7 once the initial engine is purchased. imho.
6.4's though do have their weaknesses (thus thier nickname said in hush tones) but also have a solid rep for building great power & tq. within thier design limit.
so I guess it all depends on whats important, how much "turn key" do you want (no such thing here, but you get the idea I hope) and how much $$ is in your wallet, you can get there with either engine. best of luck.

If I go 5.7 it will be with the intention of adding a proCharger at some point. As I said I want the car to be fun and reliable. I probably will only do mild bolt-ons and a cam for reliability. One of my concerns is room. I know we can drop a 440 in the A-body but headers and steering tend to have issues with room. How is the 6.4 with clearance issues?
 
The 5.7L are way more common - the 6.4L is surprisingly scarce given how many they have put into cars, trucks, etc.

The 5.7 is a very compitent engine - 375hp but there is plenty of room for a cam swap, headers, and getting to 500hp with very little work. The 6.4 is what? 485hp from the jump -

The T-56 will bolt up behind the 5.7 or 6.4 with a SBM to T-56 bellhousing. They use the same flywheel as well.
 
The 5.7L are way more common - the 6.4L is surprisingly scarce given how many they have put into cars, trucks, etc.

The 5.7 is a very compitent engine - 375hp but there is plenty of room for a cam swap, headers, and getting to 500hp with very little work. The 6.4 is what? 485hp from the jump -

The T-56 will bolt up behind the 5.7 or 6.4 with a SBM to T-56 bellhousing. They use the same flywheel as well.

Do you still need to notch the frame on the 5.7l as you do with the 6.4l to clear the Alternator?

If you run the Truck 5.7 that moves the Alternator and AC can you still run a Carbonated Manifold and can you convert that truck Fan to electric? I'd like to avoid old school fans
 
Do you still need to notch the frame on the 5.7l as you do with the 6.4l to clear the Alternator?

If you run the Truck 5.7 that moves the Alternator and AC can you still run a Carbonated Manifold and can you convert that truck Fan to electric? I'd like to avoid old school fans
You don't have to notch the rail, but, it is dang close. If you want the A/C, you'll have to run the truck front cover. No way the A/C works with the car cover. At least with true BOLT IN parts. You can just unthread the fan off of the water pump. Keep in mind, the truck fan is left hand thread(2009-present). You'll have to elaborate on the intake. If you meant "carbuerated", sure, it'll work. If you meant the car injected manifold, I'm not sure. With the forward facing TB, it probably will interfere with the accessories.
 
5.7's are cheaper than 6.4.
Stock HP though as you know, is well shy of your goal, so youll be into mods on the little wonder work horse. bolt ons alone (headers, intake, etc) will not get you there. Youll need long tubes, cam, engine/head work, tune - if running oem PCMs, etc.
6.4 is already 485hp, minor bolt ons will put you nicely past 500. It takes more to make the same % of power from a 5.7 than a 6.4 thus the trend towards going that route out the gate. With hellcat conversions being all the rage, 375hp seems sorta pathetic now days.
If your building up a 5.7 or slightly hopping a 6.4, (again, to meet your stated goal) all the rest (cooling, elect power needs, driveline, fab work, etc all would all similarly fall in line nearly the same. ie: same work & money eitherway you go...so little to be gained there on the back end, by going with the 5.7 once the initial engine is purchased. imho.
6.4's though do have their weaknesses (thus thier nickname said in hush tones) but also have a solid rep for building great power & tq. within thier design limit.
so I guess it all depends on whats important, how much "turn key" do you want (no such thing here, but you get the idea I hope) and how much $$ is in your wallet, you can get there with either engine. best of luck.
So, what is the nick name that the 6.4 has?
 
Srt is called Apache. Don't know if the truck 6.4 has a designation.
 
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