2.7 Turbo 4 Fan Club

MDSilveradoGuy · September 8, 2019

3 hours ago, Grumpy Bear said:

It's already at 375 kPa (54 psi). Indy car territory. I'm thinking it's tapping out as is.

If you look at the boost curve it's on the limiter from the hit.

Not sure where you saw that at. It runs up to 22psi of boost. It’s not really pushing any design limits - GM wasn’t stupid enough to stress it like Ford does with the EB.

Grumpy Bear · September 8, 2019

5 hours ago, MDSilveradoGuy said:

Not sure where you saw that at. It runs up to 22psi of boost. It’s not really pushing any design limits - GM wasn’t stupid enough to stress it like Ford does with the EB.

Gorehamj's post which I see I read incorrectly. I read that line at about 200 kPa or 29 psi. My bad. Thanks for making me look twice. :thumbs:

Edited September 8, 2019 by Grumpy Bear

MDSilveradoGuy · September 8, 2019

5 hours ago, Grumpy Bear said:

Gorehamj's post which I see I read incorrectly. I read that line at about 200 kPa or 29 psi. My bad. Thanks for making me look twice.

Haha no worries - what an interesting chart.

I will say that from my butt dyno and audible perspective that it is spot on. The turbo spools (and starts whistling loudly) right off idle. My neighbors used to be able to tell when I was coming up the road from the exhaust on my Colorado - now they can hear me whistling up the hill.

LT4Banger · September 9, 2019

Anybody else hopelessly waiting for some performance mods to come out for these 2.7's?!

amxguy1970 · September 9, 2019

On 9/7/2019 at 2:55 PM, mafd2 said:

You're better off than getting a Subaru on steroids.

Someone has a complex...

Tyler

kc classic · September 21, 2019

Have a question regarding the 2019 GMC sierra. In the center of the dash board, in front of the catchall is a square domed area (between the catchall and the windshield). It is about 1.5" square. What is it?

OnTheReel · September 21, 2019

3 hours ago, kc classic said:

Have a question regarding the 2019 GMC sierra. In the center of the dash board, in front of the catchall is a square domed area (between the catchall and the windshield). It is about 1.5" square. What is it?

Light sensor for the auto headlights.

808 HI · September 21, 2019

anyone upgraded there intake or exhaust? if so, what was the impact?

kc classic · September 21, 2019

That is what I was thinking. It is totally different than the old sensor.

ryan030389 · September 22, 2019

I ordered the AFE intake but it won’t be here till the end of December

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LT4Banger · September 26, 2019

Anyone else with the 2.7 having 8-speed transmission Issues? I still have a harsh shift 1-2 and 2-1 after getting the new transmission fluid.

MDSilveradoGuy · September 27, 2019

19 hours ago, LT4Banger said:

Anyone else with the 2.7 having 8-speed transmission Issues? I still have a harsh shift 1-2 and 2-1 after getting the new transmission fluid.

I have the occasional rough 1-2, the occasional 2-1, and it shudders like a wet dog pretty much all of the time under light acceleration. The 8 speed is Satan's own transmission and needs to be recalled, taken out back, and shot...

AlaskaErik · September 27, 2019

On 4/5/2019 at 8:53 AM, the wanderer said:

I suspect that little 2.7 gets better MPG than EPA. TFL Truck tested it and got like 25MPG on their Highway loop. I'm seriously considering it, but the reports of turbo lag at highway speeds does not bode well.

I plan on pulling a trailer, nothing more than 5 to 6 thousand pounds so it would work there, but I don't know. My gut tells me to let them work out the hiccups in the motor first, and fix that lag issue before I'd consider owning one in a truck I hope to keep 10 years.

The 5.3 is not that powerful compared to competition, but it's bullet proof for the most part.

I know this is an older post, but I pull a trailer in the 5 to 6 thousand pound range and my 5.3 was straining when crossing mountain ranges. And the trans temp was over 200° going uphill. No way would I ever try to tow that much with the 2.7 unless it was short distances over flat terrain. That's the whole reason I upgraded to the 6.2 and max trailering package.

heymrdjCW · September 28, 2019

I know this is an older post, but I pull a trailer in the 5 to 6 thousand pound range and my 5.3 was straining when crossing mountain ranges. And the trans temp was over 200° going uphill. No way would I ever try to tow that much with the 2.7 unless it was short distances over flat terrain. That's the whole reason I upgraded to the 6.2 and max trailering package.

Turbos get a huge benefit over NA vehicles crossing mountain ranges. If you were crossing the Rockies, you were probably down over 30% of your horsepower.

AlaskaErik · September 28, 2019

2 hours ago, heymrdjCW said:

Turbos get a huge benefit over NA vehicles crossing mountain ranges. If you were crossing the Rockies, you were probably down over 30% of your horsepower.

HP Loss = (elevation x 0.03 x horsepower @ sea level)/1000. 7000 x .03 x 420/1000 = 88.2/420 = 21% loss. I'm still pumping out more horses than a 2.7. I imagine it's the same for torque. And I have that 3.42 rear end.

Edited September 28, 2019 by AlaskaErik