if you're planning on swapping the chain out . . . the oil pan needs to be dropped . . . have fun with that.

 

you have to remove the chain when you're doin the swap right?

 

A little advice for you.

Don't mess with a good thing. Re-use your stock timing chain. Use OEM MLS GM head gaskets. Don't touch your stock lifters. There's absolutely no need to change any of that stuff. All you're doing is increasing the likelihood of botching something up. And it saves you cash too. Win win.

 

it comes off the timing gear, but it does not get "removed" It's just like the front sprocket on a bike
yep !

 

I believe you will be just fine installing the heads without milling them, maybe just a clean up cut if they need it. The machine shop can let you know when they are doing the valve job. Your new set up will basically be a iron LS2, so yes your compression ratio with the 64.5cc chambers should be about 10.9:1, where as your stock LQ9 had an advertised compression ratio of 10:1 with the 71cc 317's. It was the LQ4 that had a factory advertised 9.4:1 ratio.

 

i would absolutely do the lifters and chain, i would also add in ls2 lifter guides or drill holes in your current guides to let oil drain better. Depending on how many miles you have your stock chain can stretch and throw the timing of the cam off, be it ever so little. I wouldn't worry about the gears as i would just the chain. An ls2 chain would be a good replacement, and you have to drop the oil pan to get access to the oil sump tube bolt to remove the oil pump when changing the chain. I learned a trick from one of the forums when doing this and it was just drop the oil pan, take the bolts 3/4 of the way out not out. Then lossen the bolt holding the sump tube to the oil pump, just loose not out. Then tie a piece of fishing line around the bolt in case you drop it when taking it out. You'll see it better when you do it, but trust me use the fishing line, it's good insurance. The chain only has to come out when replacing it, you can do the cam swap with the stock chain and not have to "remove it" the oil pump will keep it from coming off the truck.
The stock lifters are not ment for higher rpm, higher spring loads, and high performance and since the heads are off already it will be easy. Down the road, if you choose to add a higher lift cam you wont have to pull the heads to add better lifters. I've heard the ls7 lifters are good for most cams guys use. However i'm not sure how they are in high spring pressure trucks, like over 400 pounds open. i opted for the morel lifters due to their design for aggressive lobes and for higher spring rates but they are an expensive overkill for most guys.
Don't order 7.4 push rods, your lifter preload will be to high with a 65cc head. you may end up with a 7.350 or 7.375. Give or take i would think your preload would go up close to .030 with a 65 cc head. Although cheaper, i would not use the gm mls gaskets, i would opt for a cometic .040 gasket in 4.030 bore instead to get a tad more compression and pull more air through the runners.

with just stock ls6 heads not ported, i would expect around 400 rwhp with your mods and maybe around a 6300-6400 peak. Make sure your converter locks it will help. who is doing your tuning, having a person at the dyno to adjust will be a big help.

 

thanks bud.. say... ya wanna come on down and help out ???

 

depending on time, i could make it down there. you could make a small gtg of it if you really wanted to. you have an 03 so Joes HPT should work on your truck as well, provided he could bring it down. Do you work with Zippy for tuning?

 

i was kinda planning on that.. in fact, allballz57 agreed to maybe have me over to his place to do the swap... but if i dont need any special tools, (that i do not already have), we could just do it at my place.. BBQ\Beer\entertainment is on me.. and Id cover your travel costs...even give ya a couch to crash on , if needed..

 

Sound like a good time to me. Food, beer, horse power....what could go wrong.