M20 Turbo. Which oil to use?

[Nitro Nick]

Bumping an old thread. Just ordered the VR1 20w50 synthetic for my turbo m20 build.

Any reason you guys run non synthetic in your boosted cars? And to the OP, how was the VR1 20w50 synth?

I ended up going with royal purple synthetic 20w50. It has run good so far but i'm thinking of switching to the VR1 20w50 non synthetic.

Would also like to get some feedback on if its ok on the engine to go back to non synthetic after running synthetic for a while. I believe the engine has always run synthetic in it...

[MrBurgundy]

That shit is a myth, you can switch whenever

[Nitro Nick]

That shit is a myth, you can switch whenever

Any reason to flush out the old oil at all?

[MrBurgundy]

No, no harm if theres a little of the leftover in there. That's what synthetic blends are, just both mixed.


People like to use synthetic, because the molocule size is more uniform compaired to conventional. Thus, you have better flow. Also, most sythetic oils offer some cleaning agents in them.

This company of oil I use have formuals specific for turboed car, where the lights oils in the mix wont burn off when the hot oil sits in a hot turbo.

[Nitro Nick]

No, no harm if theres a little of the leftover in there. That's what synthetic blends are, just both mixed.


People like to use synthetic, because the molocule size is more uniform compaired to conventional. Thus, you have better flow. Also, most sythetic oils offer some cleaning agents in them.

This company of oil I use have formuals specific for turboed car, where the lights oils in the mix wont burn off when the hot oil sits in a hot turbo.

Would you be so generous to offer the name and type of oil you are using?

[MrBurgundy]

This is the brand

[Das Delfin]

^ Nick, eeuroparts in Windsor caries that exact brand. Lol the reps at their last swap meet tried convincing me and my buddy that 10w30 is preferred in with our cars (stock m20) over 20w50

[MrBurgundy]

I mean, you could use that exact grade too, I know some guys here run 5w40 without any problems.

edit; 10w30 is fine too

[cleanasse30]

I'm not sure about going synthetic to non, but I'm running Liqui Moly 2024 Synthoil Race Tech GT1 10W-60 in my turbo and the engine seems run pretty well. Valves run pretty quiet and I don't burn too much oil afaik.

M20s do NOT like light weight oil from my experiences; the tolerances aren't tight like modern engines and running light weight oil will cause oil temps to rise to an unsafe level and cause premature wear. I figure adding a turbo adds more heat to the system (upgrading your oil cooler can help), so running a higher weight oil can help compensate for the added heat by having a higher viscosity at higher temps.

[MrBurgundy]

I'm not sure about going synthetic to non

What makes you say that?

[cleanasse30]

What makes you say that?

I meant, "I don't know if there is some procedure you need to follow when switching". It doesn't really make sense that there would be, as you mentioned, since there are synthetic blends.

[digger]

non synthetic doesnt like synthetic sometimes. buy the cheapest dino oil you can and run it for a couple mins before switching to the dino oil of choice when switching from synthetic to non synthetic

[E30-Ellerman]

Amazon has cancelled my VR1 order due to not having stock of it - boooo!

I will be going with AMSOIL Z Rod 20w50. It's more expensive than the VR1 but I previously ran it in the m20 and the thing really seemed to like it. Got a deal locally on 8 quarts and signed up for a preferred customer account so it isn't too expensive. I'm a huge AMSOIL advocate.

[varg]

I use Rotella T 15W40. It has high ZDDP content which is good for our non-roller rocker valvetrains, and it's the stuff of choice for turbocharged, high-stress, high mileage OTR diesels which are harder on oil than my street driven turbo M20. Also the Rotella detergent content cleans up like nobody's business. Though my engine had a pretty clean crankcase to begin with.

[E30-Ellerman]

I use Rotella T 15W40. It has high ZDDP content which is good for our non-roller rocker valvetrains, and it's the stuff of choice for turbocharged, high-stress, high mileage OTR diesels which are harder on oil than my street driven turbo M20. Also the Rotella detergent content cleans up like nobody's business. Though my engine had a pretty clean crankcase to begin with.

How long have you been running the Rotella? I used it prior to going turbo for an oil change between my Amsoil oil changes and it worked great, no issues. I guess my only concern is synthetic vs non synthetic for the turbo and engine.

I really like Rotella 15W40 for m20's and if you've had good, long term success with it in your boosted application, I might follow your lead and switch out to it going forward.