MMX engine swap

Ive got a 2014 1500 w 5.7 hemi, just had 8hp70 trans rebuilt and new torque converter installed, thinking of getting a mmx long block, want to stay within the transmission parameters, any advice on longevity/PITA to install on the different Mmx long blocks 5.7/6.2/6.4 would be very helpful, also bad idea to run the 6.2 hellcat without supercharger?

The 485 horse SRT 6.4's use a 8hp70,but requires 91 octane fuel. The issue with a 6.2 with-out the blower would be finding an intake to fit it,and it probably wouldn't make that much more power then a stock 5.7,as it's low compression,but it'd easily live on 87 octane. Another option would be the truck 6.4,it makes 410 hp and 430 lb-ft and will live on 87.
A few more details of what you want to do with the truck would help,is it daily driver that you'll tow with,or is it strictly a toy.

This article is worth reading,as it has some good info and down at the bottom has engine specs.

Thanks wild one for any wisdom, daily driver but no towing, won’t be on the strip, the Mmx 6.2 long block has adapter plates for intake just pondering better cooling and oiling of 6.2 v 6.4 for longevity

Raminit2014 said:

Thanks wild one for any wisdom, daily driver but no towing, won’t be on the strip, the Mmx 6.2 long block has adapter plates for intake just pondering better cooling and oiling of 6.2 v 6.4 for longevity

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All SRT 6.4's after 2017 and all truck 6.4's use the same BGE block as the Hellcat does,so there's no advantage to cooling or oiling by going to the 6.2.All 6.4's use the same piston oil squirters as the 6.2,so you could upgrade any 6.4 to the Hellcat oil pump and have the same basic oiling system as the Hellcat,the only differance is the Hellcat does use an external oil cooler,but that's not included when you buy a 6.2,so if you wanted an external oil cooler you'd have to add it whether you bought a 6.2 /6.4 or 5.7. The truck 6.4 makes for a really good daily driver in a 1500,as it builds a pile of bottem end tire spinning torque,and can be ran on pump 87.Throw a set of headers on it,and you have a really nice engine that'll pull 3.21 gears easily,and works great with the stock torque convertor,and will surprise alot of cars.The SRT 6.4 makes more horsepower and torque,but it does it farther up in the rpm range,and also requires at least 91 octane fuel.

awesome info, 6.4 truck sounds like the way to go for me, thanks for the help it saved loads of time, any advice for exhaust:looking at stainlessworks long tube headers and I’m after a low deep sound that I can still hear myself think at highway speeds

Raminit2014 said:

awesome info, 6.4 truck sounds like the way to go for me, thanks for the help it saved loads of time, any advice for exhaust:looking at stainlessworks long tube headers and I’m after a low deep sound that I can still hear myself think at highway speeds

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You're on the right track with the SW long tubes,in Texas you could also get away with using a catless midpipe. I don't normally reconmend exhaust systems or mufflers,as what one guy likes,another guy might hate, but i do have a soft spot for Magnaflow catback systems

thanks again for all the info, youve Been super helpful