THankks for the info zero2sixT. One thing I'm interested In is being able to boil a set of tires if I wanted to. Does a stall do that? Would the trailblazer stall do that? A stall isn't really in the budget unless I can find a good deal.
As far as the cam, I have the xr265hr 211/218 .558/563 115 lsa. I talked the guys at TSP and he said I may only gain 10-15hp with the 220r that a lot of people run in their 6.0's. Idk if the minimal gain is worth $400. I could spend it elsewhere.
Would the smaller chamber of the 862's up my compression? How would it affect everything. I know I've got a lot of questions

 

I'm just at looking to squeeze what power I can out of it. Since I'm boring it .030 over, I'm putting flat top pistons in it. The 4.8 I had lost low end torque a little after I did the cam swap but responded very well above 3k rpm. I'm hoping I won't lose power down low with my same cam. I've never driven a 6.0 so idk what to expect

 

The tq difference between a 4.8 and 6.0 is VERY noticeable. That's a baby cam for a 6.0 and your Lowend will be strong.

 

What about you 03sierraslt? Would you put 4.8 heads/top end on a 6.0 bored .030 over?

 

The 243/799 casting heads on the 4.8 are the best head you have. They are actually the best factory cathedral port casting GM made.

I'd say you stand to gain a lot more than 10-15 HP with those heads, the 90 mm intake, and a 220 duration cam.

But like 03 said above, your current cam will make good power down low in the 370 You're gaining a lot more cubes.

Trailblazer stall is like $120. It's not the best option by far. But it's cheap and will give noticeable gains in performance.

 

I'm not sure about all the other 4.8's, maybe mine is an oddball. The driver side head is a 706 and the passenger side a 862. I'd like to have a set of 243/799's but I'll work with either my 317's or the set that's on my truck now. Have you personally, or anybody who would like to comment, ran a trailblazer TQ in their ride? If so, your thoughts are welcome!

 

I've never used one personally but I've tuned a couple trucks with them. They work fine, a little extra stall speed but nothing crazy

 

Hmm thought the 07 and up had 799s.

Tb stall is just a modestly higher stall speed. Nothing special about. Rode in a truck with one. Could not feel it. Keep the stock one if you're that uptight about it. You're leaving a lot on the table with it though

 

Your truck is normal lol..... GM did that from the factory in some cases and who knows..... maybe one 706 cracked and was swapped at some point with the 862 which is the same head from a different plant. You don't have 243's or 799's because you are still a Gen 3 which I think someone confused.

The 317 is very much the 243 head.... a little rougher casting that flows a negligible amount less with a 71 cc instead of 64 cc chamber. Same ports and valve size between the 243 and 317..... Like I said though the 317 is just a rougher looking casting for whatever reason. If you put flat tops in your 6 liter you just have built everyones holy grail Gen 3 LQ9 lol.

We put a 6 cylinder trailblazer converter behind a stock LQ9 in an 03 Silverado that got a powertrain swap. It works pretty good.... flashed to 2600 or so...... burnt tires..... did it's job. Noticeable difference over the stock junk.... Got the converter for like $50 so it was a no brainer to give it a whirl when the trans was swapped.

 

Key is he said 07 classic.... so it's still Gen 3 junk lol.