looking at doing a Gen3 swap ???

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mopwr2004a

low slung chassis
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1) which is the better to get 5.7 or the 6.4 ?
2) truck or car eng?
3) short block from a car or truck?
4) heads from truck or car?
5) intake from a car or truck?
6) trans from the car or truck?
7) pcm from a car or truck?
8) which holds up to more power the auto trans or stick shift?
9) any certain year model better then the other?

if you had to rebuild the complete engine is there manuals with torque specs and such for these engines?

I think I covered all the bases
 
First, there are lots of answers in the existing threads. Take a look around.

1.which is better - personal preference. Cost. Etc. You'll have to ask Modern Muscle about tuning for a 6.4 in an old car - not sure where that sits.
2. Car or truck front cover, either one works. Car front cover with accessories is a cleaner look. That's the only real difference. There are a few bolt holes different on the blocks, but not a big deal.
3. They are the same
4. They are the same
5. intake depends on front cover you use
6. ?
7. ?
8. ?
9. long discussion below

Rebuild - the factory service manual (available online on lxforums, links given in other threads, some by me, do a quick search)

There are really only a few different short blocks and heads offered for hemi motors since they came out in 2003.

03-08 5.7 motor - earlier ones did not have VVT, later ones had VVT. Can run them without it.
03-08 5.7 heads - good head, lowest cfm in stock form.
6.1 short block - no VVT. Good motor. Out of production.
6.1 heads - higher flowing than 03-08 heads. Hollow valves from factory.
09-current 5.7 short block - Ask someone else - I don't know.
09-current 5.7 heads - named 'Eagle' heads. Similar intake port to 6.1 heads, and similar flow to 6.1 heads with smaller chambers.
6.4 short block - Ask someone else - I don't know.
6.4 heads - called Apache's - highest flow numbers, port cross section is pretty big.

Eagle intake - plastic, has long and short runners
Apache intake - plastic, has long and short runners
03-08 5.7 intake - plastic, has long runners only, smaller intake hole than 6.1/eagle
6.1 intake - aluminum - has long runners only

You can look around for performance figures from the different combinations.

That should get you started.
 
There were some concerns with valvetrain issues in the earlier 5.7's. The 03's especially and maybe even a year or two after that had some issues with valve springs cracking. Easy enough to swap out if you're doing a rebuild anyway, but potentially an added cost to keep in mind. Everyone has different luck though. Some engines are out there with 100k+ miles with no issues and some fail in a few thousand.

As far as rebuild parts in general, the choices were pretty slim and got expensive, at least back when I did it a few years ago. There were almost no choices for rings for me, and with the dealer wanting $30 per piston for a set I was looking hard to find anything else. Ended up finding a set, but the gaps on them were pretty large. The only cam bearings available at the time as well were something like $80 a set instead of the $30 my machine shop guy was thinking they would be. Rod and crank bearings were similar, though a little more reasonably priced compared to other engines (ended up reusing mine anyway since they were in good shape). Gaskets are almost entirely O-rings, so you can reuse a lot of them if they're in good shape, but might have a harder time finding replacements if you need them.

Easy enough to rebuild the engine, nothing to unique in there compared to the older stuff. The main things to pay attention to are the rods. Most if not all the 3G Hemis use powdered metal rods, which you CAN NOT mark with a punch. Doing so will ruin them. Also, they are a cracked cap design, so each cap must go back with its respective rod and you have to be careful not to damage the rough surface when you pull them apart. The rod bolts are also torque to yield and must be replaced, but this is getting more typical in all newer engines, so it's not wildly different. Some claim that the head bolts are torque to yield as well, but I've been told by engine builders that they are not and have sucessfully reused mine so far.
 
One benefit of an engine from a truck is it might not have egr such as my engine from an 05 2500 truck.
Truck computer is less likely to have security to disable.
6) Truck trans has a yoke. Old 727 yoke fits, but only use a new yoke as the splines are slightly different.
7) match to trans
I have seen some people say 05 truck has the most options for trans tuning with a predator, but I don't really know for sure.
 
1) does the factory harness come equiped with all the connections for the auto trans and manual trans?
2) In all the vehicles that come with either trans as a option. that way you can swap from one or the other and the PCM do what its suppose to do.
3) also are the PCM's same for either trans or you have to get one that goes with that trans.

When I do this swap I think I will find me a good used truck to strip down, this would be the cheapest route to get all the parts needed.
 
mopwr2004a said:
1) does the factory harness come equiped with all the connections for the auto trans and manual trans?
2) In all the vehicles that come with either trans as a option. that way you can swap from one or the other and the PCM do what its suppose to do.
3) also are the PCM's same for either trans or you have to get one that goes with that trans.

When I do this swap I think I will find me a good used truck to strip down, this would be the cheapest route to get all the parts needed.
Click to expand...


Harness are different between the manual and Auto
PCMs are different as well
 
Uhcoog1 said:
First, there are lots of answers in the existing threads. Take a look around.

1.which is better - personal preference. Cost. Etc. You'll have to ask Modern Muscle about tuning for a 6.4 in an old car - not sure where that sits.
2. Car or truck front cover, either one works. Car front cover with accessories is a cleaner look. That's the only real difference. There are a few bolt holes different on the blocks, but not a big deal.
3. They are the same
4. They are the same
5. intake depends on front cover you use
6. ?
7. ?
8. ?
9. long discussion below

Rebuild - the factory service manual (available online on lxforums, links given in other threads, some by me, do a quick search)

There are really only a few different short blocks and heads offered for hemi motors since they came out in 2003.

03-08 5.7 motor - earlier ones did not have VVT, later ones had VVT. Can run them without it.
03-08 5.7 heads - good head, lowest cfm in stock form.
6.1 short block - no VVT. Good motor. Out of production.
6.1 heads - higher flowing than 03-08 heads. Hollow valves from factory.
09-current 5.7 short block - Ask someone else - I don't know.
09-current 5.7 heads - named 'Eagle' heads. Similar intake port to 6.1 heads, and similar flow to 6.1 heads with smaller chambers.
6.4 short block - Ask someone else - I don't know.
6.4 heads - called Apache's - highest flow numbers, port cross section is pretty big.

Eagle intake - plastic, has long and short runners
Apache intake - plastic, has long and short runners
03-08 5.7 intake - plastic, has long runners only, smaller intake hole than 6.1/eagle
6.1 intake - aluminum - has long runners only

You can look around for performance figures from the different combinations.

That should get you started.
Click to expand...

Yes we have tuning now for the 6.4L as well as engine management systems
 
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