F150 2.7 EB vs 5L V8 towing mpg
The 2.7 EB truck had a 3.55 axle, the 5.0L had a 3.31, both 10 speed auto crew can 4x4s, towing a 7000# horse trailer. The 5.0L V8 rated at 395hp/400tq did 9.8 mpg The 2.7L EB rated at 325hp/400tq...
Forum Discussion
The 2.7L is forced fed +5.9L's of air/fuel to have similar HP/Torque as the NA 5L
The 2.7L has it's piston tops see higher PSI than the 5L, so it gets way hotter..and the surface areas of both the piston top and cylinder walls has less square inches than the 5L...so that means higher BTUs must be rejected per square inch vs the 5L...meaning the thermal management system has to reject (absorb) more BTU's per volume of coolant than the 5L's cooling system...therefore the coolant must either more at a higher GPH, higher PSI and have more surface area efficiency at the radiator, which has added thermal loading from the intercooler in front of the main coolant radiator (it sees heated ambient air vs the 5L's)
How much head room did the thermal dynamics engineers design in ? The 2.7L's has to be MORE than the 5L's system to have the same duty cycle
Wonder what the piston FPM is. The gold standard for longevity is 4,000 FPM (take the piston stroke x RPM /6 is the rule of thumb to figure red line when you know the stroke). A smaller displacement might have to rev higher (even when forced fed) to attain that HP/Torque
There are more and the cam comes to mind. SMOG limits over lap, but lift and duration plays into this, which goes to how those extra forces are managed with the cam followers, rockers, valve springs, etc, etc
The 2.7L has it's piston tops see higher PSI than the 5L, so it gets way hotter..and the surface areas of both the piston top and cylinder walls has less square inches than the 5L...so that means higher BTUs must be rejected per square inch vs the 5L...meaning the thermal management system has to reject (absorb) more BTU's per volume of coolant than the 5L's cooling system...therefore the coolant must either more at a higher GPH, higher PSI and have more surface area efficiency at the radiator, which has added thermal loading from the intercooler in front of the main coolant radiator (it sees heated ambient air vs the 5L's)
How much head room did the thermal dynamics engineers design in ? The 2.7L's has to be MORE than the 5L's system to have the same duty cycle
Wonder what the piston FPM is. The gold standard for longevity is 4,000 FPM (take the piston stroke x RPM /6 is the rule of thumb to figure red line when you know the stroke). A smaller displacement might have to rev higher (even when forced fed) to attain that HP/Torque
There are more and the cam comes to mind. SMOG limits over lap, but lift and duration plays into this, which goes to how those extra forces are managed with the cam followers, rockers, valve springs, etc, etc
