Why not put a cam / long tube headers /ported intake manifold on your truck 6.4.It'll get you close to what the SRT 6.4 puts out,plus you'll still have the better truck pistons.You'll need long tube headers and tune to take advantage of the SRT's higher rpm,plus you have to swap all the front timing components / intake manifold /oil pan etc. over off your trucks 6.4 to bolt the SRT 6.4 in anyways. Check with one of the custom aftermarket cam outfits like Franks Racing (FRI) /High Horse Performance (HHP)/ Modern Muscle Xtreme (MMX) / Flying Ryan Performance (FRP) / Bischoff Engine Services (BES) / Jay Greene / Texas Speed Performance (TSP) etc for a cam spec'd for your situation.That'd give you a better cam then what the factory SRT cam is,as the 6.4 SRTS still have the same cam/lifter issues as the 5.7's and truck 6.4's have. Flying Ryan has been doing the tuning on alot of the 6.4 swapped 1500's,so i'd probably check with him for the tuning aspects,either way you're going to have to have it custom tuned. You could even look into whether there's aftermarket higher stall torque convertors available for your HD 8HP75 tranny,as you'd probably want a convertor behind the SRT 6.4 as it's down on bottom end torque compared to your trucks torque monster 6.4
I can give you good answer since that's exactly what I did. I purchased the MMX BGE camshaft on their recommendation:
https://www.modernmusclextreme.com/p-1431-64l-hemi-performance-camshaft-kit-bge-ram-na-by-mmx.aspx
They advertise a lift (.592/.552) but what came on my cam card is slightly different. If you compare this to what's been posted online for the SRT 6.4 cam (duration at .050 215/221, lift .574/.541) it actually appears to be slightly more aggressive. Even though it's advertised as a truck cam.
The kit itself lists for $1700 but when you add everything else in that's required to complete the swap it's almost $2200. Heads need to be removed to do a lifter swap so book time for a complete cam/lifter install is about 21 hours, not including springs. I also installed a Hellcat oil pump so the pan needs to come off, otherwise it's not necessary. Obviously if you're doing the work yourself none of the labor times matter much.
Compared that to purchasing a complete non-MDS long block assembly for about 5k (once you factor in the core charge return)
https://www.rosevillemoparts.com/pr...4-hemi-long-block-assembly-non-mds-2013-2017/
The SRT motor will give you .9 higher compression, better intake/exhaust valves, plus a good performance camshaft. The only thing that's "downgraded" are the head castings but again, for most situations I don't think this is worth worrying about. But what you really have is peace of mind that everything was assembled/torqued/timed properly since it's a factory assembly.
ARH headers (only one's available) are $1800 and the converter is $600 but at least labor costs are minimal since the engine is already out. Custom cam tuning through Hemifever was $400, would assume similar for a SRT motor tune. It should be relatively simple to tune since they already have a solid baseline with all the 6.4 Charger/Challenger/Jeep tunes available already. Not sure on the book time for engine replacement but safe bet it's less then a cam/lifter/spring swap.
If I did it all over again I'd probably have just gone the SRT long block route. With the headers and tune you'd have a proven 500 rwhp recipe (in a car anyway), with about factory reliability. Plus a spare motor in case anything ever happens. Would probably have cost me another $2500 over the cam swap but if I decided to sell the original BGE motor most of that would be recouped.