View Single Post
Old 11-20-2012, 08:47 PM   #86 (permalink)
serialk11r
Master EcoModder
 
Join Date: Jan 2012
Location: United States
Posts: 1,756

spyder2 - '00 Toyota MR2 Spyder
Thanks: 104
Thanked 407 Times in 312 Posts
Quote:
Originally Posted by Old Mechanic View Post
If I coast (engine on) it takes slightly longer for the engine to warm up, but I am getting better mileage since the available waste heat is lower.

regards
Mech
Intuitively this is right, the heat rejection rate doesn't go down that much after it's warm anyways since the flame temperature and exhaust temperature are much, much higher than coolant temperature.

But what about lubrication? My engine makes groaning sounds when it's cold that go away when the oil warms up...very disconcerting :/ Wasting a bit of gas at low load letting the engine warm up faster makes me feel better about my bearings. Maybe I just need a 5W-20 instead of a 10W-30.
  Reply With Quote