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Discussion Starter #41
Just from looking things over, I'm starting to become more confident that something foreign did enter the engine and caused the damage. All of the markings seem to be done by something with a straight edge, and the missing piece of the piston doesn't match the shape of the markings.
 

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Discussion Starter #42
Kind of debating on whether or not I want to pull the engine, or lower the front crossmember and drop the oil pan. I've never done that, so not sure if it'll actually save me any time over pulling the engine. I can't really make up my mind if I want to replace just the damaged piston or put forged pistons in it. I know if you have a damaged rod or piston, SRT will just swap the damaged one instead doing all of them, which leads me to believe all of them are weighted the same (per side). I already have so much into this as it is. ?
 

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I'd just pull the pan and replace just the one....seen that done on 5.7L's that have dropped a valve seat. Pull the head, replace seats, replace the one piston and go on your way.
 

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Discussion Starter #44
Unfortunately I think I also need to replace the head. This one is busted up pretty bad. I'll order a head this week and when it gets here I'll swap out the springs and that should be good to go. I haven't rotated the engine yet to check the cylinder wall, but I'm pretty sure it's fine.

IMG_20190519_125109_1558312885764.jpg

IMG_20190519_125112_1558312980492.jpg
 

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Discussion Starter #45
Last night I took the head to a cylinder head shop about an hour away and the guy said he didn't feel it was worth replacing the head, or even welding/filling the pits. He said he's going to polish the rough spots and maybe take one or two thousandths off and call it good. He said he was going to replace the valves, check the seats, vacuum test, and that'd probably be it. Fingers crossed! ?
 

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2014 Jeep Grand Cherokee Overland V6
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Oh Noes! Sorry to hear about these problems on your expensive swap.
 

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Discussion Starter #49
I guess it's the cost you pay to play.

After speaking with a few different people and Hemi techs, I believe we've all come to the conclusion that it was strictly fuel and tune related. The machine shop says the valves didn't break the pistons, so that leaves fuel and detonation. I will just buy some drop-in Mahle forged pistons, keep my stock rods, and go from there. I'll update some more when the block comes out.
 

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Discussion Starter #50
Now that the holidays are over, I've ordered some parts.

Heads have been repaired, and new Manley stainless valves are being used instead of factory Mopar valves. I know they're slightly heavier than OEM, but I don't see having any issue using them.




108842

108841
 

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Discussion Starter #52
Nah, I haven't really taken videos. I have a lot of pics of different parts of the process.

Right now I'm trying to determine which head gasket thickness to use. I'm running 11:1 pistons, and might add 8-10 psi boost in the not so distant future. If I can get down to 10.5:1 with a thicker 5 layer gasket, maybe I can run 10 psi with a lower amount of cylinder pressure, and get upwards of 250 extra horsepower.

I'll be running Demon injectors and most likely e85.
 

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Great build. If it were me I wouldnt add boost to the engine as there is a reason MOPAR supercharges a 6.2 over a 6.4. At this point you could just have a strong reliable naturally aspirated build.
 

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Discussion Starter #54 (Edited)
Great build. If it were me I wouldnt add boost to the engine as there is a reason MOPAR supercharges a 6.2 over a 6.4. At this point you could just have a strong reliable naturally aspirated build.
The reason why Mopar chose to use the 6.2 over the 6.4 was all about the bore to stroke ratio. With the 6.4, we have a ratio of 1.1:1, with the 6.2 it's at 1.15:1 and that's where the opportunity for more power comes in play. Boosting a built 6.4 isn't harmful, it's just not as optimal as a 6.2.

Latest update, I now have ARP main studs and ARP head bolts. Going to have the shop do some extra work on the heads. Not really going to spend a lot of time trying to port the heads too much but I do want to do some blending and just clean them up a bit. I don't really feel like $700 to do a full port job is worth it. The heads flow really well as it is.
 

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Discussion Starter #55
It's been a minute since my last post. Time sure does fly when you're having fun, lol.

So I got the engine back from the machine shop. The heads have been cleaned up, a little bit of blending, and flowed 352 CFM at .600 lift.

The block was bored .010 over and my new forged pistons and rods have a bob-weight of 8 grams less than my stock pistons and rods, not accounting for rod bearing weight, which should bring me closer to 4 grams or so.

I also had the crankshaft micro-polished while it was there.

I do have a few other things I'm working on. I've decided to swap in the 8HP70 transmission, using a standalone TCM, harness, and tune provided by Sound German Automotive. This will require adapting in an 8spd shifter as well. Just need to finishing some research on the driveshaft, and if I'll have to have a custom shaft made.

More to come soon.
 

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2014 Durango RT, 392 Hemi, Eibach Coils, 22" Hellcat Reps, Corsa Exhaust
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Sounds like your swap turned into an entirely different beast. I just did a 20 JGC 392 swap into my 14 DD rwd and it was a quick and easy swap. Basically took a day and a half. It's way easier to drop the sub frame than pull it from the top. And fortunately, the 14 electronics and wire harness are compatible. Anyway, good luck with it. I'll be interested to see how it turns out and how many ponies it's got.
 

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Discussion Starter #58
The swap itself was simple. It took a few hours to swap just the engine. The biggest issue for me was the motor mounts, exhaust manifolds, and flex plate didn't line up with my vehicle. The oil pan is also different, the dip stick tube location is different, the crank had a pilot bushing that needed removed. I didn't know any of that until I tried to install the engine. Next was my PCM. Since my PCM is the older 4 post type, it's not a simple direct swap like it is in the newer vehicles. This requires running all of the wiring and connecting it to each sensor individually.

Sure, I could have saved a lot of time if my Durango was a 2014 or newer as it's practically plug and play. But this all gave me opportunities, and the ability to forge it up, have heads done, and make it a lot stronger and ready to have fun.
 

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I have a 2014 DD SSV AWD 5.7 I want to swap in a 6.4. What's the best compatibility to make this happen what year what vehicle?
TIA
 

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2014 Durango RT, 392 Hemi, Eibach Coils, 22" Hellcat Reps, Corsa Exhaust
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I have a 2014 DD SSV AWD 5.7 I want to swap in a 6.4. What's the best compatibility to make this happen what year what vehicle?
TIA
I used a 20 JGC SRT motor and it was very easy. I believe any of the DD SRT and 14 up JGC SRT is compatible.
 
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