Starting a 6.4 Hemi swap

[TwoCarGarageYT]

I'll admit I haven't read every work of every post, but a couple things stuck out to me reading through...

6.4 vs. 5.7 - beyond the benefits you laid out, just do some research on the BGE (Big Gas Engine) they are meant to take some abuse. Durability and additional cooling meant to take boost

4.88 vs 5.13 - You'll have enough torque to move 40's, especially in 4lo. I would gear for the highway, and I think you'll likely want to be in that 1800-2200 rpm range. For me (40s and 4.88s) that 70-75 mph. 4lo is an additional consideration. Granted I have more power with the 448ci stroker unit, but with the 4:1 tcase i"m pushing through 1 ton brakes.

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[Flyin6]

I'll admit I haven't read every work of every post, but a couple things stuck out to me reading through...

6.4 vs. 5.7 - beyond the benefits you laid out, just do some research on the BGE (Big Gas Engine) they are meant to take some abuse. Durability and additional cooling meant to take boost

4.88 vs 5.13 - You'll have enough torque to move 40's, especially in 4lo. I would gear for the highway, and I think you'll likely want to be in that 1800-2200 rpm range. For me (40s and 4.88s) that 70-75 mph. 4lo is an additional consideration. Granted I have more power with the 448ci stroker unit, but with the 4:1 tcase i"m pushing through 1 ton brakes.

I've done a lot of research on the 6.4 vs the 5.7...Two different motors in some ways. I chose the 6.4 SRT engine modified for the Jeep...

Gears. Right now, with an RTT and a rack, I want to say I have a "heavy" overland setup, which would suggest 4.88's with at least a 37" tire. But I have deleted a ton of stuff...Back seat, aluminum bumper, rear hitch, second battery. But then added a long-arm suspension, heavier steering, and RSE sliders, so the weight may be a wash between now and stock.
I would favor a 4.56 gear for highway driving, as you suggest, for the current tire size. I do not think I am willing to do both the gear change (again) and the 40" tire upgrade...

 

[Flyin6]

Oh, and on the brake thing: My plan was to go to TerraFlex's big brake kit. However, they can't accept any more than a 4.72" Backspace. My Borah wheels have a 5.73" B.S.
My solution is to install Ram dually studs which are M14 X 1.5 and 3.5" long. They have the same knurl (.630") as the stock Gladiator studs. Toss in a 1" wheel spacer and bingo, bigger brakes and able to keep the same wheel.

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