6.4l intake on a 5.7l hemi. Anyone done it?

[427invader]

I'm probably gonna have to take my 5.7l hemi apart in a week or so. Has anyone put a 6.4l 392cui (Hellcat) intake and a 90mm throttle body on a 5.7l 345cui? Should be pretty straight forward swap. Appears as though everything bolts up the same and shouldn't need a tune. Any info pros or cons is greatly appreciated.

 

[CanuckRam1313]

I'm probably gonna have to take my 5.7l hemi apart in a week or so. Has anyone put a 6.4l 392cui (Hellcat) intake and a 90mm throttle body on a 5.7l 345cui? Should be pretty straight forward swap. Appears as though everything bolts up the same and shouldn't need a tune. Any info pros or cons is greatly appreciated.

Unclear as to why you'd opt to put a 90mm TB on a stock 5.7 with zero mods!!!
You'll gain zero, and likely hurt the overall operating efficiency of the engine altogether.

And, unless you're going to tune it, don't waste a penny on putting a 6.4 intake manifold and injectors on a stock 5.7 either.

If you're 5.7 requires rebuilding etc., put your cash towards a 6.4 engine and an 8spd transmission upgrade with long tubes, etc......

Just my $0.02

 

[427invader]

Mods so far are: Class II Camshafts (213-219 degrees; hydraulic roller)Basic Operating Range - 1,200-5,200 rpmNo CARB EOFair idle quality, good low-midrange torque/horsepowerAdvertised exhaust duration - 272 degreesAdvertised intake duration - 266 degreesExhaust duration at 0.050 in. lift - 219 degreesExhaust valve lift - 0.575 in.Intake duration at 0.050 in. lift - 213 degreesIntake valve lift - 0.575 in.LSA - 114 degrees. Melling high volume oil pumpM452HV.

2003-2008 5.7L HEMI CNC Ported Heads by Modern Muscle Performance.​

 

[Recoil]

I don't really think you will notice any HP improvements without a tune. Your PCM will still think it has a stock intake.

 

[HemiLonestar]

I'm probably gonna have to take my 5.7l hemi apart in a week or so. Has anyone put a 6.4l 392cui (Hellcat) intake and a 90mm throttle body on a 5.7l 345cui? Should be pretty straight forward swap. Appears as though everything bolts up the same and shouldn't need a tune. Any info pros or cons is greatly appreciated.

So which is it lol? Hellcat or 392 (they aren't the same.....)?
Regardless, this not a workable plan for you. Unless you are willing to completely rearrange your accessory drive, your AC compressor will be in the way.
Forgetting that, no matter how much cam you have in a pre-eagle, you still have stock pre-eagle valves and port size. In order to clear the temp sensor boss on pre-eagle blocks you'd need spacers; on top of that they'd have to be spacer-adapters because of the gross port mismatch (which MMX does actually make for a nice hefty sum, they also used to make an accessory drive kit but I don't think they do anymore). On top of that (as was previously mentioned), a 90mm TB.....all 5.7's & 6.4's use the same size TB...90mm is Hellcat size. You somehow think your cammed, small head, stock intake pre-eagle 5.7 is gonna need more air than a stock apache 392, much less as a supercharged 6.2.......?
The 2004 PCM is vastly more tunable than the 2003 but it is still more limited than the 2005 (this is why 2003 peeps will switch directly to the 05); 2006+ are CAN based and not compatible. Don't go too wild with the cam or you won't be able to tune it with the factory computer.