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Posted
On 6/22/2022 at 1:51 PM, 4banger said:

Well that's the stigma anyway. It's just not how it works though. Case in point, 1989 dodge introduces the cummins turbo diesel, nice long stroke low hp but way more torque than hp rating and at way lower rpm than the naturally aspirated competition. In an era of big block v8's as the alternatives. And that tiny little 5.9 liter displacement could have a big camper on, 4 horses in the trailer behind and head to the mountains getting good mileage while the v8's wheezed so hard and sucked fuel at open bar rates. The reason that cummins was able to do that with it's anemic initial ratings of 160/170 hp and 400/410 ft/lbs torque...was because the turbos eliminate elevation...they only lose 0.05% power per 1000' but the naturally aspirated 3% per 1000' so elevation largely eliminated and easy to equal the big block competitors if not surpass them.

 

The 2.7t is the same formula...long stroke turbo with way more torque than horsepower and at lower rpm than naturally aspirated peak torque numbers. Stay with me here...I live Calgary Alberta, 4000' elevation. Where I live I have 22 ft/lbs more torque than the 6.2 and I have it at lower rpms. I'm sorry but this little boosted 4banger is far more truck designed engine than either of the 2 v8's which are both short stroke motors fyi. The 5.3 isn't really in the same league when elevation comes into play, they are equal at sea level but the 2.7 walks away from there. The 6.2 still has 62 more hp at my elevation despite that 22 ft/lbs torque deficit but it's burning 30% more fuel around town here, I know as I just returned a 2022 6.2 rental that I just put about 1000 miles on and picked up my 2.7 two days ago and closing in on it's first tank of break-in at about 260 miles right now and just under half tank on it's first tank! and it's 30% less fuel by the mpg rating on both trucks dashes back to back. And this torque pull is effortless...torque spins those tires, that's why diesels are preferred for the big trucks...it's not the diesel, it's the turbo's that make them special and able to pull down respectable mileage and power combined, turbo regardless of gas type is going to run lifts and tires and loads better than the v8's at most elevations above sea level where 60% of us live and with less gas consumed for everything but the longest steepest heaviest pulls. 

You seem to know what you’re talking about 

 

I have a question 

 

I got a 2023 TB Lt with the 4 cylinder 2.7 turbo

Came stock with 275/65/18 tires and 3.42 rear axle ratio.

If I install 295/70/18 will it affect performance significantly?  I do not care about MPGS.

I’m concerned about sluggishness. 

(already know the 296/70/18 tires clear UCA’S on stock 18” wheels)

Posted
On 12/26/2022 at 5:35 PM, Nestor Romero said:

You seem to know what you’re talking about 

 

I have a question 

 

I got a 2023 TB Lt with the 4 cylinder 2.7 turbo

Came stock with 275/65/18 tires and 3.42 rear axle ratio.

If I install 295/70/18 will it affect performance significantly?  I do not care about MPGS.

I’m concerned about sluggishness. 

(already know the 296/70/18 tires clear UCA’S on stock 18” wheels)

it's just rolling mass and drag, you've added more contact patch(drag) and whatever the rolling mass is, I know the stock 275 65r20's that came on my custom were 78.4 lbs per corner as I weighed them before and after I changed them, I ended up doing something super rare and went to a lighter weight combo and went 4 lbs lighter per corner with a 17" lightweight wheel and skinny tire the exact same height. I gained performance and mileage even going to load range 3 all terrain but most aftermarket wheels are absolute slugs, heavy wheels and heavy tires, most aim for looks vs performance enhancements, things in motion want to stay in motion, heavier wheels/tires don't want to change direction as easily and take more work to get up to speed and more work to slow down (brakes)...having said all that, your turbo will spin them every bit as good as the v8's, you've got more torque at lower rpm, the truck least likely to feel them is the diesel at it's got 460 ft/lbs at a mere 1500 rpm which is half of the the 2.7's peak torque rating

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