The lash adjusters that keep tension on the cam followers (rockers). They get filled up with debris and dont let the valves close all the way. I would definitely replace them.

 

That's it! I knew it wasn't valve springs and I couldn't remember the name. Thanks!

 

Awesome thanks for the info! I will start looking into getting parts. I mainly want to freshen the engine up it only has 104k on it and there were no issues when i pulled it just wanted to put a diesel in lol. I'm planning on all the gaskets including head gaskets because the motor is out. Same with the trans but I have a pretty good grasp on that since i was looking into it for the cummins swap originally. Other than gaskets I was only curious about common parts that need to be cleaned or replaced at 100-200k. Might as well do what i can while its out of the truck.

 

Headers and stud kit?

 

Bently...come on...I know I've gone dark for a while but I didn't forget everything lol. yeah those are on my list as well, im between long and short tub eheaders. I may try to make some long tube ones work since I've got the engine out.

Are there any kind of better intake manifolds/throttle bodies that will actually make a difference? The truck does not have to pass emissions next year so i just need to pass the emissions test for my next inspection and that's it. That being said i still cant do the cummins because of the video taping thing. I can do some stuff that may make i fail because of emissions just cant do it immediately such as an EGR delete which i will be doing because i cut my EGR pipe to get it off since it was rusted on to my manifold lol.

 

I'm also doing a EGR delete when the Header's get installed. Search my threads and you can find the EGR plate I ordered off eBay. I ordered the wrong Header's from Thorley and they won't swap them out. Good thing about the Thorley's is they come with a new Y-pipe. 5star will set my tunes for EGR delete and make an Emissions tune too.

I've also seen plenty on here mention the Remflex Gaskets. $40 on Amazon for my V10.

I wasn't trying to demean your knowledge, didn't know if you were going maintenance only or slight upgrade to the 5.4

 

No worries at all man, was just making a joke lol. Thanks for the info on the EGR delete I’ll read through your threads now!

I’ve been thinking today and I’m thinking about doing some upgrades vs strictly maintenance. Not sure if anyone here watches it but B is for Build on YouTube was upgrading a mustang and was installing injectors etc. I’ve done SO much research on the Cummins that I have no real idea about what should be done to the 5.4 to give her some more umph. Would injectors give me any real gains in a 2v? Obviously I would get her tuned by 5star after the fact but I’m just curious what performance upgrades are worth the effort.

 

Gears. Everything else is after gears.

 

Injectors are not needed at your power level, and as far as bolt on stuff, it’s a bit of a waste of time on the modular engine. The real way to performance on these things is going to be through compression, cams, and port work. I’ll stress the compression part, if you can swap the pistons with some cobra 4.6 flat top pistons (cobra, Mach 1, Lincoln mark 8, those are all flat top or close to it), that would get your compression closer to 10.5:1 and then get a little bigger cam to compliment the compression.


5.4l intake manifolds are hard to get ahold of and if you were really interested in going the performance way, the best thing to do is get an edelbrock 4.6l intake and either get the 5.4l adapter plates or get the intake cut in the middle and widened. This is a short runner intake though and you would likely notice a decrease in torque but a big increase in upper rpm performance.

Long story short, unless you are getting serious with the engine, don’t change injectors. That combo I listed above would work very well with 24lbs injectors.

 

My lifted 5.4 with 38's loved it when I swapped out to the 5.38 gears. I had mustang shorty headers on mine with the egr delete. Once I did that it pulled my big boat no problem.

 

I'd vote for gears, that will definitely help. Another option would be to get a custom ground camshaft done. With a custom ground camshaft you can have them CNC grind it to your preferences. I know someone who had that dont to get some better performance out of the engine.

The guy worked with the folks at that shop and told them what he was looking for and what he has been doing with the truck towing etc and the guy told him what he could do with making the camshaft give the engine some better performance.

 

Thanks for all the info guys! I forgot to add earlier i was going to do gears, i originally was going to before i decided on doing the cummins but now going back i will definitely get them. What ratio would you guys suggest? i was looking into like 4.30 (forget if that's the right ratio might be 4.33) originally with a 4" lift and 35x12.50 tires, think that is low enough or should I go to more like 4.56? I am not going bigger than 35's because as it is already i have 1/2" of clearance on my garage door lol.

 

With 35's I'd suggest 4.88's myself. 4.30 came with stock size 31.6 tires. 4.56 with 35s would not even match that.

 

I agree with this recommendation. My 2003 had the 5.4/ZF6 combo and when I up-sized tires to 315/75R16 (~34" OD), I did a gear swap to 4.88s and I was very happy with the overall results. It was very driveable in town and while running at ~2500 RPM on the highway at 70-75 mph, it was far from unbearable. I think that going with anything numerically lower than 4.88s will disappoint you.

 

Awesome thanks for the info guys! I will go with the 4.88s then, from what I remember I may have been looking at those a while ago. Of course i dumped all my research and saved links once i decided to go with the cummins.

Good new fellas, I will finally have some down time from traveling for work form now until after the new year so I am going to take as much time as i can and make progress on the truck. Unfortunately i wont be buying any parts such as gears etc for a while but i will take the time to get the motor and trans separated, spruced up, painted etc and i am going to finish the interior/engine bay.

I was thinking last night on my flight home...can the airdog be used with gas? I have my Ex tank now mounted and everything but its set up for diesel. Was thinking about running a second fill neck to just under the tailgate to fill the rear tank and then using the airdog as a transfer tank to my old tank that I'm going to put back in...thoughts on this? basically I'm trying to recreate the older OBS style dual tanks. or if i can find a way to make the Ex tank work with my old set up i may just run that.

Oh or i can use them to store two different fuel types and get towing tunes etc so i can transfer in like 91 or something once my stock tank is on E into the stock tank and run that.