Tuned turbo engine - Do I need a higher performance oil?

[beanbag137]

Mobil 1 0w40 API SP or Havoline 0W40 will work for your application.

I’d use an A3/B4 oil.

I think these are "full SAPS" oils which are supposed to be bad for intake deposit buildup?

 

[chris719]

I think these are "full SAPS" oils which are supposed to be bad for intake deposit buildup?

I feel the difference is probably overstated. There’s not much evidence other than the Lubrizol pdf that wasn’t really an apples-to-apples comparison. If you compare the top of C3 (0.8%) to typical A3/B4 (1.0-1.2%) there is a difference but it’s not massive. PCV design is the issue mainly; a BMW N54 engine is going to need blasting often even with low SAPS, but N55 will go far longer between cleanings on full SAPS. If your engine is prone to IVD buildup then sure, pick a C3 based oil instead. I’d run ESP X3 / X4, Motul X-Clean Gen 2, etc.

 

[userfriendly]

I think these are "full SAPS" oils which are supposed to be bad for intake deposit buildup?

From Chevron 2024 SalesFax:

Supreme SAE 40 API SP
40C 116.2
100C 13.4
150C 4.0
NOACK of base oil 4.0
Flash Point 272C !!

Havoline 10w40 API SP
40C 95.7
100C 14.0
HTHS 3.8
SA 0.8
P .077
Zn .087

Havoline 5w40 (not the Euro offering)
40C 83.6
100C 13.4
HTHS 3.7
NOACK 9.0
P .096
Zn .105

Havoline 0w40
40C 74.9
100C 13.3
HTHS 3.7
NOACK 10.0
P .096
Zn .105

I posted the SAE 40 specs because I use single grade engine oils when possible. Ambient cold starts above 5C or 40F.

 

[scrllock]

I've had a M7.5R for about 4 and a half years, on my third motor and 7th turbo. Been up to 530whp or so, lots of ethanol, tried nearly all of the PCV/catch can products, and the usual spark plug/oil experiments. Not saying I know what's right to do (stay 100% stock, obviously), but I've seen some things on these cars.


You're street-driving a mechanically 100% stock engine. 220F is normal summer highway cruising temps. Other euro cars will hit 240+ at low load on 30-40 weight oils.
Driving in the way you're describing would be fine for 100k+ even on a built motor tuned to make 500HP. In your case, I'm sure a 5w30 would be sufficient. I've always liked the way my motors sounded on API SL Castrol 5w30.

If you want to improve valve deposits, retrofit MPI and give it the beans regularly. A slightly nicer oil is nothing compared to actually washing the valves in petrol. If it's been 40-50k since you last changed your PCV, maybe snag the latest revision as preventative maintenance.

Also, ditch the EQT tune, find someone who tapers boost off more at redline. Those IS38s are junk and like to pop. If anything their stage 1 tunes are worse since they target the same amount of boost as a stage 2 tune, but with more backpressure from the stock downpipe.

 

[beanbag137]

Thank you for the suggestions. Unfortunately I live in California and can't implement some of the more useful ones.

 

[Jetronic]

I think these are "full SAPS" oils which are supposed to be bad for intake deposit buildup?

********.

Ash is not black for starters, it's grey/white. Carbon is black though, unless in diamond form. Carbon comes from fuel and other hydrocarbons, not from the metallic additive package. Have you seen intake deposits any other colour than black?