2008 5.7L engine rebuild

[xtremeroller]

I'm just about ready to pull the engine out of my recently purchased 2008 project truck to do a complete rebuild. It's going to be a play truck so I'm leaning toward doing a performance rebuild. It has a really rough idle and will not stay running unless you keep giving it gas. Throwing code P0300. Any tips or tricks on making this process easy? It's not my fault driver so I am not in any hurry to get it back together. I want to do this right the first time.

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[xtremeroller]

No one has any helpfull insight on this?? If I were asking about lift kits or tire sizes, there would be hundreds of comments here.

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[Max1329]

How do your injectors look? It sounds like your just getting crappy fuel delivery

 

[Kyle Kinnamon]

Im in the middle of rebuilding my 06 5.7 hemi. my brother seized the motor aug 2017 and im just now tearing into it. just dropped the crank of at the machine shop today. its been a pain in the ass trying to find videos and write ups on this engine. Just take your time, take lots of pictures and put everything in labeled zip lock bags, even if its getting replaced. makes it much easier when putting it back together. especially if its over the course of a few weeks.

 

[xtremeroller]

I'm not sure on the injectors yet. I haven't been able to pull the motor yet due to work and other issues going on. I'm leaning more toward doing a full rebuild on the motor using forged internals. I want reliable performance when I do this rebuild.

 

[LoneWolf3574]

How do your spark plugs look? Are they fouled? Are they something other than copper (ie iridium or platinum)? I ask because these 5.7L Hemi's work best using copper plugs according to everyone here. Personally, I've never tried anything else since I bought my truck.

There are multiple reasons you're getting a P0300 including fuel delivery, injectors, spark, and plugs. Even if you go with a full on rebuild using forged parts, I believe it best to figure out the root cause of your multiple misfires before tearing apart the engine.

https://www.obd-codes.com/p0300

 

[chrisp2493]

What info are you looking for? I’ve done two rebuilds so far, my current engine is a stroker. What power level are you trying to go for? Forged internals aren’t exactly necessary unless you plan on boosting it.


I Bleed Ram Trucks

 

[xtremeroller]

I'm wondering if just going with a 392 stroker kit would be more cost effective than doing a stock rebuild and trying to go for 450 to 500hp. I want the build to be reliable whichever direction I go.

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[chrisp2493]

I'm wondering if just going with a 392 stroker kit would be more cost effective than doing a stock rebuild and trying to go for 450 to 500hp. I want the build to be reliable whichever direction I go.

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A proper stroker kit build that will be worth the trouble will run you $5,000-$6,000 easy especially if you invest is a worthwhile set of heads to tie the build together


I Bleed Ram Trucks

 

[Fast69Mopar]

Like one of the earlier posters had mentioned, diagnose the P0300 Multiple Cylinder Misfire DTC first.

You don't want to overhaul this motor or build another one only to find out you have a fuel/air/spark concern that causes your new motor to run like crap.

I have built more 5.7 and 6.1 HEMI's than I can remember. If you have any questions or need guidance and advice don't hesitate to ask.

Now, with 5.7 parts being so readily available for performance builds it only makes sense to me to add some power and reliability while you have it apart.

Too save some money on forged internals do some eBay shopping and find a 6.1 crankshaft. I just picked one up a few weeks ago for $150.00

For the cylinder heads, you can deck the heads to make the combustion chambers smaller to bump the compression up a bit and some handy porting and polishing will definitely help in the flow department.

The more work you can do yourself the easier it will be on the pocketbook. Machine work is cheap where I live in Texas. Your largest expense is probably going to be a quality forged piston. The small parts can add up tootif you aren't paying attention.

Good luck with the build and ask questions.