Replacing a high mile 5.7 for a lower mile one

I've either been lucky or good.....My 2007 Ram 1500 has 394,500 miles on it and it is still running.
It has thrown some codes lately. Cylinder 5 misfire, cylinder 6 misfire....Plus I'm smelling the sweet smell of coolant in the exhaust. Sometimes it has steam in the exhaust in warm weather. It is time to make some changes.
In 2009 with about 59,000 miles, 2 of the MDS lifters on the right bank conked out. They had to pull the head to hone 2 cylinders that had carbon buildup. I'm wondering of they actually pulled both heads and staked the intake seats because I haven't heard of anyone else with this many miles on a 5.7 engine. I've never overheated it so maybe if the valve seats weren't staked, I avoided the dreaded "dropped seat" issue just by being responsible.
I don't like the new trucks. I don't like the styling, the busy interiors, the lack of a CD player, the knob for a shifter....or the exorbitant prices for even a 3 year old low mile used one.
I'm keeping THIS one.

It has some small scratches and dents but is still pretty clean overall.
On Thursday I put $500 down on a $2250 1007 5.7 at a wrecking yard. I got to see and hear it run. The truck was hit hard in the rear, hence the reason for it being totaled. It looked a little rough, as if it were owned by a guy on a dirt road. The miles were supposed to be 83,000 but the odometer wasn't showing when we looked.
No ticks once it ran for a few minutes....it was smooth and quiet. No smoke but the MIL/Check Engine light was on. I didn't try to read the code.
My plan is to pick it up on Wednesday. I'll pull the heads and send them to my guy for a rebuild and to have the intake seats staked. If there isn't any ridge in the cylinders, I'll just replace the gaskets, oil pump, timing set and screw it all back together. If all goes well, I'll at least have rolled back the clock a bit. If I can get another 200,000 out of this replacement engine, that would be fine. The 5.7 cores are abundant for now.
I'm curious about any performance difference that I might see. As an engine wears, you lose a little performance over time. With an engine swap back to something like this, I just don't know what to expect. It isn't like the truck is a slug as it is but a power increase would be nice.

Stick a 392 cam in it while it's apart!

It is tempting to make upgrades but I have to keep the truck emission legal. The 392 cam is VVT, my truck is not.
One guy suggested the Eagle heads but that would bump my compression up too high.

I think the Apache head would yield a lower compression ratio.

Apache heads won't work without some block mods. Eagle's will bolt right on but to get compression down you need different head gaskets that are ~$250 ish and probably new pushrods. The Eagle's won't do much for you without a cam. I think your original plan is sound. Good luck.

Thank you.
From what I have read, the dropped seats often occurs after the engine is run hot, shut down then restarted.
I've never gotten close to overheating. Once the radiator showed signs of leaking, I replaced it. Same with the water pump.
I'll save this original engine and decide what to do with it. I may build a wilder version with a long stroke crank, better heads and cam but still with streetable compression. I've considered the 5.7 Hemi and a 500 or 518 OD
for this car....

Why would he have to mod the block for 6.4 heads? I haven't had to for any of the swaps I done...

Oh and my 2007 5.7 I bought from the auction with 2 dropped valve seats and rusty crusty antifreeze blown all over the engine compartment, I have seen tons of dropped seats in 5.7s and EVERY. SINGLE. ONE. had signs of over heating. I proceded to put on a pair of eagle heads I had laying around with stock head gaskets again no issues except it now needs 91 octane to keep the knock sensors from showing activity, has significantly more power and it gets much better MPG than my 06 with a bone stock 5.7 with less miles (also an auction pickup with dropped seat and lots of signs of overheating).

They are not big blocks designed in the 1950s, 12 to 1 is fine on pump premium, thats what mine came out to CCing everything when I put them on my early 5.7.

Dave won't he start throwing codes with the Eagle Heads?

Not unless he screws something else up! Ive been running this one for several months now and it runs awesome. Not even a tune though I am sure a quality tune would make it better.

I have since eliminated my makeshift EGR tube with no codes either.

https://board.moparts.org/ubbthread...eagle-swap-on-early-5-7.html#Post3106431

Great write up

If this truck were just a toy, that would be tempting.
I'm going to drive this truck like I always have. All weather, all conditions. Empty, loaded, towing or not. I can't risk building it where I'm always obligated to running the most expensive fuel. Right now, I can used 87 octane with no noticeable drop off in mileage or performance.
If I have to bore this block and replace the pistons, the Eagle heads may make sense. I could get dished pistons and keep the compression in the mid 10s to allow me to get by on 89 octane.

I get significantly better MPG with the high compression engine (and tight double quench pads and more airflow) than the stock one, it costs about the same per mile and is more fun to drive, quite a bit further range, more power everywhere in the RPM range, a lot less downshifting to maintain speed up hills, very snappy reving.... I have not found a downside since I had the heads laying around and the engine apart anyhow. If your really concerned about the compression ratio you could run a 6.1 cam to bleed a little cylinder pressure or you can run the thick head gaskets like everyone else does but the reduced quench is gonna make it even more detonation prone.

HRDave what kind of fuel mileage improvement are you seeing. How many mpgs did you avg before v/s after the swap?

Can you not just put a complete OEM eagle 2009+ hemi in it?

I bought both of my current chargers (06 and 07) from auction with dropped seats so I don't have any before and after comparisons but they are both same gears, tires, trans... so they should be reasonably comparable to each other now and I usually get about 20% more mpg under similar driving conditions with the one I put the eagle heads on (07).

I do understand the relationship between compression and efficiency. The same issues were in play in the early 70s when ratios dropped from the 9.5 to 10.5 range down to the low 8s. Less squeeze, worse power and mileage.
I've never heard my engine detonate using 87 octane. Not once. I have noticed better mileage when using 89.
I'm keeping the MDS so any non stock cam is out.
It would be great to just swap in a later model 6.4 but with any 2009+ engine I'd expect there to be differences in wiring, fuel flow rates, computer, etc.
If there was a published example of this being done without major fabrication, I'd love to know about it.
Regardless.....
If I do need to bore this block, this would be a great excuse to use the better heads.

I'd check the LX car forums, must be a slew of 04-10 charger/300 that have been through the swap. check ram forums too - its probably easier than you'd think

I'm not certain but I suspect that there are numerous differences in the wiring, the fuel injectors, the PCM and who knows what else.

I brought the engine home today.

I tore it down to a short block.

I cleaned the tops of the pistons to look for any ID markings.

These numbers ....I did an internet search and only found one reference to it....some guy rebuilding his 2006 5.7 engine saw these numbers on the pistons.

I still see cross hatch and there is no ridge at the top of the cylinders.

I'll take the heads and the short block to my machinist tomorrow.

. [/quote]Dave won't he start throwing codes with the Eagle Heads? [/quote]

Yeah, I would. The Eagle heads don't have an EGR valve. Mine does.

Dave won't he start throwing codes with the Eagle Heads? [/quote]

Yeah, I would. The Eagle heads don't have an EGR valve. Mine does. [/quote]


Takes about 2 minutes with a hand drill to add the passages, it is zero issue at all.

If I knew of someone nearby that knew about this stuff, it sure would help. This isn't like the old days where just about every machine shop guy knew the specs of the common engines off the top of his head.
I'm sure there are plenty of tricks to wake up these engines and make more power while still remaining reliable.
I hate to come across like the crusty old dude that refuses to deviate from stock because thats how they built them when they were new so thats how I'm going to build this one.

That isn't the case. Emissions compliance is a big factor if you live where there is testing. Adding EGR is an interesting thought but I'd still have to consider the compression ratio difference.
It was stated that there was a fuel economy increase with the higher compression. I understand that. I'm still pondering if it balances out ....overall fuel costs for each mile.
I'm guessing that all of the gains in HP from 2008 to the 2009+ engines is from multiple points. VVT, improved efficiency in the port design, active intake manifolds, different exhaust manifolds, etc.
The 2008 was rated at 345 HP. The 2009 was 395. Is 50 HP in a 5000 lb truck that noticeable? How much of that gain is from the heads? I'd suspect that the biggest gains were from the cam timing.
If a 2006-2008 5.7 were fitted with these Eagle heads bumping compression about 2 points, I see that one would gain power from the compression increase as well as from the improved head design.
In the past, it was thought that each point of compression can make a difference in HP of about 4%. 8% added to 345 is 372. Add in the increases from the head flow, are we now closing in on the Eagle 395 HP number?
For a classic car, I don't mind running 91 octane premium all the time. I don't drive the car nearly as much as this truck.

I brought the heads and the short block to the machinist. He says that unless they are abused, most late model engines run a long time. He liked how the cylinders walls looked but plans to take a micrometer to them to see if the engine has been bored over. That weird 21_015 number has to mean something.
He thought the heads looked fine at first glance but will disassemble and check the valve guides and report back.
He works part time a few days a week. The 440 block I had there last Summer took awhile and that was just a bore/hone/deck/clean/cam bearings. That took 2 months.
If all he has to do is go through the heads, the turnaround will be quicker. I'm going to take my fuel injectors to a friend that has a cleaning business.

I get more than 8% better economy, more like 20% but it comes from more than just increased engine efficency from compression increase. The ratio increase alone is just over 2.5 points more so about 10% less fuel just on that but there is also more airflow, double quench pads. Also the increased TQ from all that means a lot less downshifting around here so if you live and drive on long flat roads you may not see much improvement from that if it don't down shift a lot already. Without tuning the extra airflow and exhaust flow means the ratio is gonna be leaned out significantly when it is not adjusting for the o2 sensor readings. Also since it requires less throttle opening and higher vacuum in the intake the computer advances the timing more so all in all there is a lot more advantage to the swap that strictly having more compression.

I was just throwing numbers around for the purposes of comparison.

I am curious about why they juggled the combustion chamber and piston design. What advantages did they seek?
A flatter piston and smaller chamber provides what gains? With dual spark plugs, I don't see any gains in flame travel. Did this allow for more overlap with the cam?

A flat piston has less surface area for it to absorb heat. Smaller chamber more compression and the dual quench pads give the fuel/air mix and extra mix right bee four ignition. It also flows more air because of improved ports and bigger valves.

Thanks.
I made it nearly 400,000 miles on a stock engine, I'll just default to a stock replacement.
For a hot rod, I'd be open to deviating from a factory type arrangement but this truck is a daily driver, commuter, tow rig, parts hauler and it needs to be able to run on any grade of available gas.

I have yet to hear from anyone that has logged more miles on their original gas engine.
Yesterday I rolled over 395,000 miles.
Each cold start brings a MIL. That is Dodge/Mopar speak for Malfunction Indicator Light.
Everyone else calls it a Check Engine light but I try to follow what the Dodge owners manual dictates.
The MIL is always a random misfire or a cylinder 6 misfire. Once the engine is running a couple of minutes, the idle smooths out and it idles great. You'd never know that the engine has this many miles on it. It does blow a little steam if it has been ran, shut down and restarted a bit later. I suspect the head gaskets are leaking a minute amount of coolant into the chambers. I smell the sweet tang of coolant from the exhaust pipes even if it isn't pushing any steam.
Power seems on par with what it has been for years but it may have incrementally slowed down a bit. I'm tempted to run it on a dyno before I pull it for the swap, just to have a before and after comparison.
The machinist has had the replacement engine for almost 3 weeks. I don't know if he has done anything yet. I'm going to check in with him tomorrow. I don't like to be a pain in the ass to people but I also don't want this to drag out 3 months. I want to have the engine here before THIS one craps out.