Cold start fuel consumption Mobil-Shell-Castrol

[civicist]

Trying to improve cold start fuel consumption. i am currently using magnatec 10w40 and the kinematic viscosities are pretty high. i am thinking of using Mobil Super 3000 Formula Fe 5w30 or Shell Helix Ultra AB 5w30 or Castrol Edge 0w30.

I am looking for low cold start up fuel consumption and protection as well as high rev protection. I do push the engine to its limits couple of times a day. It revs up to 7200 rpm. Please see below numbers and recommend me what i am looking for.

Mobil Super 3000 X1 Formula FE 5w30 Value

cSt @ 40º C 58.6
cSt @ 100º C 10.6
Sulfated Ash, wt%, ASTM D 874 1.05
Phosphorous 0.1
Flash Point, ºC, ASTM D 92 225
Density @15º C kg/l, ASTM D 4052 0.85
Pour Point, ºC, ASTM D 97 -51

Shell Helix Ultra AB 5w30 Value

cSt @ 40º C 64.7
cSt @ 100º C 11.4
Density @15º C kg/l, ASTM D 4052 0.848
Pour Point, ºC, ASTM D 97 -42

Castrol Edge 0w30 Value

cSt @ 40º C 72
cSt @ 100º C 12.2
TBN mg KOH 10.3
Flash Point, ºC, ASTM D 92 212
Density @15º C kg/l, ASTM D 4052 0.838
Pour Point, ºC, ASTM D 97 -54

 

[dparm]

The HTHS and VI are more representative of operating viscosities than the KV@40 & KV@100.

That Mobil Super 3000 X1 Formula FE 5w30 is a low-HTHS oil (ACEA A5) targeted more at fuel economy. The other two are high-HTHS oils (ACEA B4) that are meant for performance-oriented applications. They will be thicker at operating temperatures but provide better wear protection.

 

[NateDN10]

Also, the oil will probably not impact your fuel use enough to notice. More fuel is used on cold starts mostly to warm up the engine and catalyst. Obviously thick oil takes more energy to pump, but it's still a relatively small contribution to overall fuel use.

 

[dparm]

That's what I thought, too, Nate. I'd just stick with an oil that has good MRV and VI if you want the best cold-start PROTECTION.

 

[mechtech2]

Use a 5-30. Mileage and power should improve somewhat, but not by massive amounts.
The oil has nothing to do with cold start fuel economy. that is controlled by the coolant temp sensor and computer [makes it run rich - more fuel when cold].

 

[civicist]

i am aware of the closed and open loop cycles and o2 censor readings but isnt a thicker-heavier oil more resistant to flow compared to oils with lower kinematic viscosity? oil pump must be working a lot harder in order to push the oil through the passages. in this respect what would be your suggestion between shell and castrol?