Mobil 1 15w-50, 20hrs; 2234cc VW Air Cooled Turbo

[Nick1994]

I changed the oil last October in my sand rail and finally sent in the oil sample. It was in the sump for 10 months, and probably 20 engine hours but those are some harsh hours. I'm shocked this UOA didn't show the oil full of dirt and sand.

The engine was built in the mid-90s, it's an air-cooled VW engine, stroked and built to 2234cc's, turbocharged, and when the oil was changed in 12/2023, fuel injected. Dyno'd at 249hp to the wheel, though the mechanic said the 20 year old street tires I've got were slipping on the dyno. Had a Fram Endurance oil filter on it for this OCI. Also, this engine is very low hours since it was built.

When it was dual-carb it ran 110 octane leaded race fuel, now it runs 100 octane unleaded. I'm sure there was some residual leaded fuel in the tank. The current fill is the same 15w50 and I'll probably change it again in October (it sits all summer) at 15-20 hours. Will run an UOA at that time too. Has a Royal Purple filter now.

 

[fantastic]

Pb extremely high. Possibly bearing not replaced during rebuild or bearings not replaceable? Not much else to do other than let her rip & wear a helmet for the possible bang.

 

[930.engineering]

for reference:

Thread 'Built/Turbo Air-Cooled VW Oil'

Dec 28, 2022

Hi guys, wondering what you'd recommend for oil in my new to me sand rail? I'll post the specs below. It's a really low mile engine, its use is strictly for performance. The guy I bought it from said he put some 20w50 in it, I'm thinking a 5w40 might be suited better? While it'll be driven hard, it'll only be used in cooler months, under 90* outside. Some starts in the 30's will be normal too. Would a zinc additive be beneficial too?

It's a 2234cc built VW motor
84x92
CB Performance Street Eliminator heads
Weber IDF 44 dual carbs
Roller rockers
Garrett T3T4 Hybrid Turbo
Deep oil sump and...

• Nick1994
• Replies: 10
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles

• 

 

[KEVINK0000]

This engine begs for 20w50 VR1. M1 15w50 is not as good in extreme usage in my opinion. The lead is primarily from fuel. If that was bearing lead, this engine would not be running.

 

[fantastic]

The lead is primarily from fuel. If that was bearing lead, this engine would not be running.

Says "Unleaded Fuel" right in the UOA.

 

[maineiac]

Nick1994:​

"I'm sure there was some residual leaded fuel in the tank."

 

[Gasbuggy]

Nick1994:​

"I'm sure there was some residual leaded fuel in the tank."

Isn't leaded fuel no longer real lead but a substitute? Does it still show up that way in tests?

 

[53' Stude]

Pb extremely high. Possibly bearing not replaced during rebuild or bearings not replaceable? Not much else to do other than let her rip & wear a helmet for the possible bang.

Leaded fuel captain

 

[fantastic]

Leaded fuel captain

You're right, thanks

 

[addyguy]

Looks like fun!