2.7 turbo in Silverado?

[Cujet]

I wonder how it would compare with the V-8 as you add altitude? I live at 5050 above sea level. I wonder how it would do say with a load going up I-70?

The simplified lapse rate is generally considered to be 3% per 1000 feet. So a normally aspirated engine will lose about 15% power at 5000 feet elevation.

A 355HP Chevy 5.3L would make about 301HP
A 420HP Chevy 6.2L would make about 357HP

At about 10000 feet the 6.2L would make the same HP as the 2.7 turbo 4 at sea level

However, even though turbo engines can be tuned to make rated HP at reasonable altitudes, they typically fall short by almost 1/2 what a normally aspirated engine loses. The turbo needs to run at ever higher RPMs to achieve rated boost as we increase elevation/altitude. This increases turbine inlet pressure (exhaust back pressure) and reduces output.

 

[MSCH]

I wonder how it would compare with the V-8 as you add altitude? I live at 5050 above sea level. I wonder how it would do say with a load going up I-70?

generally turbocharged engines will outperform naturally aspirated engine's at altitude, simply because they can pump in more air than a naturally aspirated engine can.

 

[Brons2]

However, even though turbo engines can be tuned to make rated HP at reasonable altitudes, they typically fall short by almost 1/2 what a normally aspirated engine loses. The turbo needs to run at ever higher RPMs to achieve rated boost as we increase elevation/altitude. This increases turbine inlet pressure (exhaust back pressure) and reduces output.

You having an aircraft background, may be familiar with turbo-normalized piston singles. The intent of these is to keep sea level manifold pressure at higher altitudes to retain sea level power.

Of course that said, driving a propeller is a constant load activity not subject to the response rate concerns you would have on an automotive application. So you can basically put whatever size turbo on there that you need to make a certain boost level at a certain altitude, and the extra boost at lower altitudes would be bled off via the wastegate.

 

[MSCH]

You having an aircraft background, may be familiar with turbo-normalized piston singles. The intent of these is to keep sea level manifold pressure at higher altitudes to retain sea level power.

Of course that said, driving a propeller is a constant load activity not subject to the response rate concerns you would have on an automotive application. So you can basically put whatever size turbo on there that you need to make a certain boost level at a certain altitude, and the extra boost at lower altitudes would be bled off via the wastegate.

most modern vehicles use some type of VGT.
which can contro, boost pressure, turbo speed and exhaust back pressure far more precisely than
a older waste-gated turbo.

 

[I<3oil]

I've been looking at this product for my wife's next Outback.

https://www.autostopeliminator.com/

I have one on our Odyssey. Love it.

 

[Rmay635703]

as long as you understand no one ever saved any money driving a diesel and that they bought it for the performance.
First time the CEL comes on you'll find out how much the SCR systems costs to maintain.
but those mini diesels sure are powerful and get really good fuel economy until you learn the fuel costs 30% more and it costs more to service.

I and my father did, but that was the 80’s diesels and the diesels cost less up front than the same as gas and had less maintenance, cheaper fuel and better economy than the gas version


Funny to think but There are a few articles saying the 3.0 is carrying GM becoming most of its sales outselling ford and dodge this year.