Mods Because Of Social Distancing

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donjetman

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Social distancing has given me way too much time. I'm ordering parts for mods I've only been dreaming about doing to our Yukon. I like to experiment, so

I've ordered and I'm adding:
a) a remote mounted 1 gal oil tank to increase sump capacity, Viair# 91014
b) a oil cooler, Hayden# 696
c) a 180* thermostat

and if the social distancing continues long enough, I'm gonna:
d) remove the heads so as to extract all the broken exh manifold bolts.
e) install headers
f) hallow out, or replace w/fake, the cats
g) get the engine tuned for 87 octane and two O2 sensors.
h) get the trans tuned

I have 2 drag race cars, that's why I drive the Yukon like a lil ol lady. I get my kicks at the track. Remember, we mainly use this vehicle to drive at the speed limit to and from a second home 1000 miles away.

Any part# suggestions/link?
Anything else while it's down and/or apart?

Thanks
 

Joseph Garcia

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There is an old saying that during times of tragedy, there are also times for opportunity.

I wish you the best of outcomes on your project.
 

intheburbs

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The 6.2 is a high-compression engine. Isn't it self-defeating to tune it for 87? The main reason I still run 93 exclusively in mine is because I don't trust the computer/knock sensors to adjust the timing so as to not cause engine damage running on 87. Wouldn't you need to replace the crank to a shorter stroke or something like that to reduce the compression ratio to make it really feasible to run 87 while eliminating the possibility of damage to the engine?
 
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A few different ways to lower compression. Different pistons, larger combustion chambers in the heads, thicker head gaskets.

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18
 

Dantheman1540

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They are designed from the factory for the masses. I would assume the factory tune is very "safe" as far as timing goes that way if one of the 6.2 trucks gets filled with 87 and sits for say 6 months it will still run just fine. I'd always recommend 93 but since hes getting it tuned on 87 I'd like to assume the tuner will compensate for the 10.4-1 comp ratio and it will likely be fine without boost.
 

Foggy

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I'm spending WAY too much $$$ on mine too !!!!!
And the "tune" will prob just change the timing tables a bit to
run on 87 octane. Leaving a little power on the table, but in just
a commuter it's no big deal. Esp if you have a hard time getting
premium or it's super expensive in your area
 
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donjetman

donjetman

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Back in the day, 1975, my first car was a 69 Pontiac GTO 350hp 400" RamAir III engine. It had 10.75 to 1 CR. I lived 30 miles out in the country from where I worked(auto parts store). Sometimes I wouldn't have enough $$ to put enough Premium Leaded gas(ethyl) in it to get me home and back, so I would put regular leaded in it. I had to drive it like a Lil ol lady to keep from hurtin it(valve rattle or detonation).

Then in the mid to late eighties, I had a stock full size rwd Blazer, w/9 to 1 CR 305" 2 barrell and stock HEI ignition, that I towed my race trailer around with. It was also my daily driver. So as to get the best gas mileage and not hurt the engine, I installed a MSD timing control device to the ignition. I had a dial on the dash so I could adjust the timing on the fly. I would advance the timing till I heard a little pinging, then back it off a tad. The Yukon does this without my input.

These days, or vehicles are much more flexible about their fuel requirements. My Toy FJ Cruiser, w/202k miles and no issues, has 10.5 to 1 CR and I've never run anything but 87 octane in it. When I first bought this Yukon, all I ran in it was 87 octane. Then once between TX and Colorado I got a Knock sensor warning. Since then I've been running 89 octane in it.

If I had my choice of engines in our Yukon, it would be the 4.8. That's all we mainly need. On rare occasions I need to pull my race racer around town a bit.

Fuel here in the San Antonio area is always pretty cheap, relatively speaking, and I've never had a problem getting Premium unleaded. As a matter of fact, I have access anytime I want at 2 little local country airports to purchase/pump 100LL avgas. Its running about $4/gal now. I went and bought some earlier today for my lawn equipment.
 
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OR VietVet

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No mods for my 02 but I was also not planning anything till warmer weather anyway. I just bought that, new to me, 2005 Harley FatBoy 15th anniversary and when it is not raining and I am off work, I will be on it.

The only mods I really want to do is some new lights and do some paint touch up around this thing. I have been spending a bit of $$$$ on some tool upgrades for the recent set I bought. He was a motorhome tech and he did not have some of the auto/light truck specialty tools I needed but the tool box and what he had was very nice for his selling price.
 

iamdub

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Social distancing has given me way too much time. I'm ordering parts for mods I've only been dreaming about doing to our Yukon. I like to experiment, so

I've ordered and I'm adding:
a) a remote mounted 1 gal oil tank to increase sump capacity, Viair# 91014
b) a oil cooler, Hayden# 696
c) a 180* thermostat

and if the social distancing continues long enough, I'm gonna:
d) remove the heads so as to extract all the broken exh manifold bolts.
e) install headers
f) hallow out, or replace w/fake, the cats
g) get the engine tuned for 87 octane and two O2 sensors.
h) get the trans tuned

I have 2 drag race cars, that's why I drive the Yukon like a lil ol lady. I get my kicks at the track. Remember, we mainly use this vehicle to drive at the speed limit to and from a second home 1000 miles away.

Any part# suggestions/link?
Anything else while it's down and/or apart?

Thanks

What kind of headers? If you're getting it de-tuned to favor 87, I'd assume it's strictly for cost savings. Opening up the exhaust with longtubes(?) and hollowed/deleted cats would yield even more power loss, albeit in the lower RPM. I understand detuning it to optimize it on the cheaper gas if you don't need the 6.2's full power capability. The money saved on the fuel would eventually pay for itself. But why spend money on parts to decrease it's power? This would likely further reduce it's efficiency at the speeds it's most often driven, possibly negating any fuel savings, and there would be no return on the investment other than aesthetics and sound.

Not arguing with your plan, just confused by it. Items "E" and "F" say "I want mo powa!" But item "G" says "Nah, just playin. I want it to be slower but cheaper"
 

iamdub

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The 6.2 is a high-compression engine. Isn't it self-defeating to tune it for 87? The main reason I still run 93 exclusively in mine is because I don't trust the computer/knock sensors to adjust the timing so as to not cause engine damage running on 87. Wouldn't you need to replace the crank to a shorter stroke or something like that to reduce the compression ratio to make it really feasible to run 87 while eliminating the possibility of damage to the engine?

The factory tune is optimized for ~91-93 and so it is recommended in the manual. But it'll simply retard the timing if it detects knock. No need to lower the compression. In hotter weather, my 5.3 will knock on 89 or lower if I'm ******* the throttle. So I run 89 at the lowest during the winter and 93 exclusively any other time.
 

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