Hello all,

[EDIT2] In an attempt to get a lil more feedback/reads I have placed a Readers Digest/shortened version of what I am looking for at post 4. Didn't realize how much I had written til I reread it.[/EDIT2]

I understand that most of this has been beaten to death, so I used the search first and read til my eyes bleed, now I just have a few questions/verification to ask.

I have a 2002 Chevy 1500HD with a bone stock LQ4 (6.0L) with almost 110k miles on it being backed up by a stock 4L80e. So far the only drive train mod is a Hooker AeroChamber muffler on order that will be welded in in place of the factory muffler. I am looking to bump up the power out of it a little bit. I have no intention of now nor anytime in the future changing out the torque converter, therefor I would like to keep most of my power gain to the off-idle to ~6000 range. This should allow for a more usable powerband for daily driving and moving around a crew cab short box land yacht. After some extensive reading, here is what I have planned, please provide feedback as you see necessary.

Replace the cam, valve springs, and pushrods. The cam I would be looking at would be either Comp Cams XR259 (206/212, .515"/.522", 112LSA) or Comp Cams Cams XR265 (212/218, .522"/.529", 114 LSA) or equivalent. [EDIT] The valve springs would probably be the Z06 yellow springs. I have read bad things about even the new Comp Cams 918s. Would I need new/hardened pushrods at 110k? [/EDIT]

While I am in there replacing the cam, I intend to replace the cam chain with the heavy duty one from the LS2, GM P/N 12586482. This should bolt right in correct?

Another thing I have contemplated doing as long as I am torn down for replacing the cam is to replace the heads with either the 243 casting or 799 casting (the head sticky says they are basically the same). This would allow me to bump up the compression into the 10.5:1 area, which should still be very streetable on 91 octane. I have read that you can pick up a set of stock 243 heads from Patriot Performance for reasonably cheap than include valves, springs, retainers. Would I be able to reuse my rockers off my LQ4 with these heads or would I be required to get new ones? Or do the stock 243 heads from Patriot Performance come with new rockers? [EDIT]These 243 heads from Patriot are just a cast made by Patriot of the GM 243 head correct? They are not original GM correct?[/EDIT]

All that I have read seems to state that the 243 head is a drop in replacement for the 317(LQ4 head). However, no one has explicitly stated whether or not it has all the proper holes drilled and tapped to mount the LQ4 accessories. Is the 243 head an exact drop in replacement for the 317? ie no changing hoses, drilling holes, doing anything other than unbolting the 317 and bolting in the 243. I assume while the heads are off it would be as good of time as any to put some new plastic lifter holders in as well?

Anything else I should be checking/replacing while I am in there besides the standard seals/gaskets/orings?

Oh and to top it all off I plan on having the computer mail-order tuned, unless someone knows a good tuner in the frigid reaches of Montana.

Thank you,
Conrad

 

Apparently I have not read enough posts on here. lol Turns out that a lot of people are having problems with the Comp Cams 918 springs. So I guess it is Z06 yellows for me then. I need whatever config I choose to last another 100k so I am willing to sacrifice that extra 10-20hp/tq for longevity.

If I go w/ the Patriot 243 heads they already come w/ the Z06 yellow springs correct?

Thanks,
Conrad

 

yeah dont get the 918s

 

Let me try again, this time in a more Readers Digest version of it.

Have 2002 1500HD w/ LQ4 w/ 110k on it, bone stock. Want to bump up the power a lil bit w/o loosing anything on the bottom end. Keeping the stock torque converter from here to forever.

Looking at one of these two cams.
Comp Cams XR259 (206/212, .515"/.522", 112 LSA)
Comp Cams XR265 (212/218, .522"/.529", 114 LSA)
w/ Z06 Yellow springs and possibly new pushrods.
While in there swapping out the cam chain for a LS2 unit. GM P/N 12586482. This fit?

Then probably putting on a set of 243 heads, maybe now maybe in the future. I hear Patriot Performance has them for cheap. These a Patriot casting or an original GM part? Best I know these come w/ valves, springs, retainer, etc. Can I reuse my LQ4 rockers w/ these new heads? 243 heads have all the right accessory holes to drop in replace the 317 on the LQ4 now?

Top it off w/ a mail order tune. Post up you comments on my choices. I plan on changing out all the appropriate seals and gaskets on the way back out. Any other maintenance I should do while in there? Guessing at ~+50hp/tq maybe a lil more.

Thanks,
Conrad

P.S. Thanks Dan, my reason to go back on the 918s was based on one of your other to the point posts against getting 918s.