since the motor runs hotter with the turbo now, should I switch to 10w-40?

 

No.

 

thanks for the explanation!

 

Metal expands as it gets hotter, therefore result in tighter clearances. Running a thicker oil would just make the oil pump work harder.

 

Smart man ^^

 

excessive heat also breaks down a lubricants ability to lubricate. therefore I think that I'll go with 3 quarts I'd 10w40 and 1 quart of 20w50.

 

^^ not necessary.. the first number is for cold start, you will just have trouble starting if its cold.. but mixing two different oil i say is bad idea.. unless you will be building a race tc like ptuning, i dont see a good reason going high viscosity.. maybe 5w40 will be fine but the way to go is going full synthetic and running an oil cooler but for mildly boosted street car just go with oem spec

 

No the clearance tolerances in the bearings with in the motor is very very small.. You go with a higher weight or viscosity you may starve areas in the motor of oil.. Stay with the recommended oil just add alittle more..

 

Do it the right way:

Stick with stock weight.

Get an oil cooler.

 

i run 5w-20