Thor Forums

[Beau388]

Originally Posted by Long & Winding road

Thats good to know Beau, What about the HP and TQ? Does it feel more powerful overall or just sometimes?
Any MPG improvements (or decrease) on long trips (interstate driving)?

As you are probably aware, any increase in power in motor homes is subjective. With normally aspirated engines, more RPMs equals more power. To think you will perceive any power increase with 415 cuin. pushing 18,000 lbs, would be wishful thinking. At 56 lbs per hp, this is the same as driving a 3200 lb car with 57 hp; however, the throttle response with the tune is much crisper making it feel like there is more power. The 0 to 60 mph time is still in the 24 second range. The fuel mileage or lack of is a result of driving habits, vehicles weight and total drag (aero + tire friction). Engine efficiency can be changed only a little unless the actual compression ratio changes. Even though the V-10 original design dates from the late 1980s and it was first produced in 1998, the combustion chamber has been changed to increase efficiency five different times. An engines max torque per cuin is an indicate of engine efficiency. For instance, the current V-10 has 1.01 ftlbs of torque per cuin, where as a new Vette engine has 1.12 ft lbs of torque per cuin. So, the answer to better engine efficiency is more compression and better fuel atomization (direct injection in the 3,000 psi range). Hopefully the new Ford 447 cuin V-8 engine will have 10 to 12% increase in efficiency and coupled with a new 8-sp trans will get about 0.8 more miles per gallon. For now. I am perfectly happy getting 7.92 mph @ 60 mph over the last 25,000 miles on 85-89 octane gasoline in my 3 year old coach.