All the work really paid off....

[Marky Dissod]

Yes, I should probably consider upgrading the brakes. As the transmission and torque converter are still original,
I'm leaning towards placing both proactively at this point. Maybe when things stabilize, a much-needed road trip to see Nick for that transmission upgrade.

No one ever regrets a brake upgrade unless it was badly engineered or poorly installed, which is why I'm all for GM OE brake update-upgrades.

As for the transmission (6L80?) & torque converter, in your case I'd
a. blindly buy a torque converter upgrade - THE overarching 6L80 failure mode & culprit is the OE torque converter clutch taking out the rest of the 6L80
replace that, the 6L80 is very likely to last MUCH longer than you think even if you don't upgrade the torque converter or its clutch
b. you mentioned you got tuned? If so, you can do 'a', or not, but do a used ATF analysis either way,
that'll let you know how much clutch material your 6L80 is shedding
c. since the 6L80's nature is to compensate for wear by adjusting its operating parameters, it'll be less obvious how 'old' or 'worn' it is,
until it's literally about to schidt itself. I shudder to think of that happening en route to hospital.
You may want your tuner or diagnostic mech to take a look at realtime data to see how the 6L80 is doing.
d. by now there ought to be quite a few competitively priced 6L80 upgrades,
maybe some that'll give you a core credit and/or extend the warranty on what you bought when you send back your old one.
Very few NYC transmission shops rebuild transmissions anymore; they tend to remove & replace and send back the bad one as a core to rebuilders.

...
pondering taking an ly6 and boring it out to 6.2L with appropriate upgrades for the head and camshaft for the H2 eventually.

If you're looking for a 6.2L, just get a 6.2L (time is also money), then delete Engine Half@$$.
I'd be very wary of a bore-out unless it was cleaned obsessively to perfection.
I myself am pretty much sold on finding a 6.0L - ANY 6.0L - and using either 862/706 holy heads or 243/799 holy heads,
whichever gets closest to 10.7 SCR WITHOUT going over (depends on piston's valve relief volumes).

In fact I'd not be surprised if (in your case) a conscientiously constructed 6.0L would be cheaper to get and build than a 6.2L, would perform comparably,
and save on MpG when you're not in a hurry.

 

[rdezs]

I've been looking at that option on the 6 l as well. The H2 really benefits from low end torque... The newer 6.0 with VVT is tempting. Unfortunately though with almost all of the camshaft upgrades, it moves the torque power band several hundred RPM higher. (When compared to where it is on the VVT version) Off-road or in heavy snow, especially in an 8,000 lb vehicle, doesn't help if you don't get any torque till 1800 RPM. So many options to think about. The l94 in my wife's Escalade, when I did the AFM delete I retained the VVT by using an l92 oem camshaft. Ordered new from GM performance. In the h2, that's a very doable option instead of the and I think that came OEM in the 2008-2009 models

 

[j91z28d1]

if you're concerned about off idle tq with a small truck cam, and are going to replace the torque converter anyways, just get a slightly looser one. few 100 rpms more will allow it to get moving easier and idle cleaner because it's under less load in gear.

 

[Marky Dissod]

if you're concerned about off idle tq with a small truck cam, and are going to replace the torque converter anyways, just get a slightly looser one.
few 100 rpms more will allow it to get moving easier and idle cleaner because it's under less load in gear.

Can't recommend this in the H2, famous for eating (both) transmissions more quickly simply due to its extra weight.
The same torque converter will be looser when pushed by a 6.0L compared to the same being pushed by a 5.3L (or even a 5.7L).
In other words, you don't need a looser converter, you need a 6.0L that makes MORE power under 2400RpM so the engine loosens the converter.
That way you don't lose part-throttle response when driving daisy.

Come to think of it, the 6.0L I'd build would suit your H2 even better than my Tahoe.
Think better gearing would be more fruitful for your H2, and would preserve your transmission for longer too - might even improve MpG.

If those aren't enough, then you choose a cam that makes similar peak power but MORE torque UNDER 2400RpM than GM originally intended.