Here is exactly how much power the all-new 2020 Ford F-250 Super Duty 7.3-liter “Godzilla” gas V8 is putting down to the ground. It’s not as much as you may have hoped.
This is part two of a two part series. The first part is a dyno comparison between a 2020 6.7-liter Power Stroke and a 2019 turbo-diesel V8 engines.
The 7.3-liter gas V8 is completely new. Ford calls it a big block engine. It uses push rod valve actuation that makes for a more compact overall engine size. Ford says this engine is specifically built for heavy duty and commercial truck applications with lots of low-end torque. Let’s find out exactly how much power it’s putting down in the real world.
This test is brought to you by our friends at 5 Star Tuning and HP Tuners. The guys at 5 Star just purchased several 2020 Super Duty trucks you see here. They will be testing these trucks in the real world for the next year in order to develop and bring you the latest diesel and gas engine tunes.
This test is a direct comparison between an older stock 6.2-liter gas V8 and the new stock 2020 7.3-liter engine.
6.2L Gas V8
The heavy-duty version of the 6.2-liter gas V8 has been around for a while. It’s factory rated at 385 hp and 430 lb-ft of torque, and it’s mated to a 6-speed automatic transmission. The truck you see tested here is a 2017 model with over 70,000 miles. This particular truck has a stock engine programming, but it is equipped with a performance air intake system from AFE Power, and a performance exhaust system by Magnaflow. The dyno is configured with 20% load/resistence to allow for approximately a six second dyno pull.
They are running the 6.2-liter F-250 in 3rd gear.
3.73 rear axle ratio * 1.51 (3rd gear ratio) = 5.632 ratio @ 95 MPH.
Here are the results after three consecutive runs as measured at the WHEELS.
335.7 whp, 332.8 whp, 337.0 whp => average 335.2 whp
371.3 lb-ft, 365.8 lb-ft, 371.4 lb-ft => average 369.5 lb-ft of torque
7.3L Gas V8 – Godzilla
The new 2020 7.3-liter gas engine is rated at 430 hp and 475 lb-ft of torque at the crank. This represent an approximate 10.5% horsepower and 9.5% torque increase over the 6.2-liter gas engine.
The guys at 5 Star purchased a 2020 F-250 Tremor crew cab 4×4 with a 4.30 rear axle ratio. They put it on the same dyno as the 6.2-liter truck just about 30 minutes later. The dyno load/resistance is once again set at 20%.
Is it fair to compare a 6.2L-powered truck with stock 33-inch tires against a new Tremor truck with 35-inch tires? I asked this question to Price at 5 Star Tuning. Price said that the slightly larger tire is very small disadvantage on the dyno. He said that both trucks are running 18-inch wheels, which is good. Variance in wheel diameter affects power measurement in a more significant way according to 5 Star Tuning. This is not the case here.
They are running the 7.3L Tremor in 6th gear.
4.30 rear axle ratio * 1.28 (6th gear ratio) = 5.504 ratio @ 95 MPH.
Here are the 2020 7.3-liter results after three consecutive runs, once again measured at the WHEELS.
356.3 whp, 360.5 whp, 358.0 whp => average 358.3 whp
409.0 lb-ft, 406.6 lb-ft, 406.3 lb-ft => average 407.3 lb-ft of torque.
If you look at the dyno power graphs, you can see that the 7.3-liter V8 make a lot more torque that the smaller gas engine between 2,250 – 4,000 rpm. This is precisely where the torque and power are really needed in a heavy duty truck.
The big 7.3-liter gasser make about 23.1 horsepower more than the 6.2-liter at the top end. It also makes 37.8 lb-ft of torque more.
The 7.3-liter wheel power numbers look good, but they are not mind-blowing. It’s good to see very good torque numbers from this engine. What does it mean for the estimated power at the crank? It’s safe to estimate a 20% drivetrain power loss for a heavy duty pickup truck, although we do not know the precise losses.
If you add 20% to the 7.3-liter wheel power numbers, the estimated power output at the crank comes to 430 horsepower and 488.8 lb-ft of torque. This is very close to what Ford specifies as the factory rating at the crank. This new big gasser is approaching the 500 lb-ft torque mark.
This testing was done the same day and on the same dyno as the 2020 vs 2019 Diesel V8 Super Duty comparison.
You can be sure that we will be testing these trucks in many more way, including fuel efficiency testing and off-roading.