But you're getting ahead of yourself. The chain will last the life of the truck but some feel it's good to do around 150 or 200k. I don't know. Didn't do anything for mine. How'd you know there was slack when changing the water pump? It's a lot deeper into the engine. And there's supposed to be some slack. Like I said, my new double roller Cloyes had the same slack as the old one. It's way too early to tear that deep into it.

And headers can easily warp once installed. Or the gasket failed. Header flanges are never as durable as stock manifolds. I'd blame the header way before the head.

If it's your daily and not just a toy, then leave it as stock as you can. It will yield the most life that way.

 

Changing the cam and such will also require a new tune for it to run right.

 

With the low miles, I think it's a great idea to put nice heads and a cam on your engine. Definitely change the timing set. The new chain was much tighter and my truck runs smoother since I changed it. Get Remflex gaskets for your headers.

 

How thick is the flange on your headers? The biggest reason reason headers leak is that the flange is too thin and doesn't evenly compress the gasket. My Excursion has 5/8" thick flanges on a set of Banks headers and my daughter's truck has Manzo headers (from fleabay) with around a 1/2" flange. The EX never leaked, we used copper gaskets first on Brooke's truck and replaced them with Remflex gaskets. They haven't leaked since. Most cheap headers only have a 3/16 or 1/4" flange and don't spread the pressure evenly across the exhaust port.

I haven't seen many people happy with Hughes, I've never done business with them though. Search for Odessa or Clearwater EQ heads. They also have a stock head that is supposed to be better than the stock Mopar heads. It doesn't sound like you're trying to build a race engine, I'd look for a cam that works from idle to 4000-5500 RPM. Most of the time you'll be in the 1500-3500 range in a daily driver. I'd look at Lunati or Comp Cams. You could get a set of Harland Sharp 1.7 rocker arms for around $400 and not have to worry about getting a tuner for the ECM. I'm not sure if a small cam needs a tuner or not. It would work better with a tune though.

Lots of guys on here have 200- 250,000 on their engines. You'll have a lot of time to enjoy whatever mods you decide to do. Let us know what you do. Please take pictures. Lots of pictures. LOL

 

They have a 3/8" flange. You are correct in that this will not be a racer. I'm just looking to get it to finally be able to get up and go while having a little fun putting it all together. This would be my first build so it's a learning experience but i do have help so I'm not going at it completely blind.

 

https://www.ebay.com/itm/Manzo-Stain...-/380821454331

Try the Remflex gaskets first, otherwise It looks like these have a thicker flange. You have to scroll down quite aways to see pictures of them.