Upper cyl lube reccomendation

[Thingfish]

I have a sub 14K mile Subaru WRX. It runs high boost and tuned quite rich. I am worried about cylinder washdown and its related wear.
I currently use about 5oz per 15 gallons MMO.
My question is, should I remain using MMO ? Should I look to a 2 stroke oil ?

The car is cat-less, and the wideband O2 is changed at a regular interval.

 

[forcedtalon]

Why are you running it so rich?? What fuel octane are you running? What is your wideband voltage on a full boost pull? Do you have any black smoke comming out your exhaust on a pull?
Get your car on a dyno and have it tuned for the correct A/F ratio with your everyday fuel and boost so your not putting gas in the oil if thats the case.
Problem with MMO or anykind of oil additive in the fuel will lower the the octane of the fuel causing detionation to occur. I would not worry about runnning a upper cylinder lube on that motor and is normally recomended when running alcohol injetion or alcholol fuels. Just run a real high quality synthetic. Redline 10/30 is a real good oil that can take abuse and spools up the turbo faster than a 40WT.

 

[Thingfish]

Well, its 10.5:1 or so at the tq peak, and tapers to about 11:1 at redline. Thats what this car liked.
I do not know the voltage from the sensor, the Cobb streeTuner ( how I log ) just gives the ratio not voltage.
Crappy Nevada 91 on the street , and c-16 at the track. And yes, a bit of black smoke, the inside of the exhaust pipe is has alot of black soot.
I run GC.(green)

One of my concerns was from a member of our local club, tuned rich and running M1 T&Suv comming back with only 90 psi a hole. In a 16 month old car.

 

[forcedtalon]

Try tuning it to 11:1 to start the pull to and ending at 11:5 on pump gas. You want to get rid of that black smoke out the exhaust but the black inside the pipe is fine since it doesnt have a cat.
Im not fimilar with that motor but does it have a knock sensor???
On C-16 you can run it leaner around the 12.0 range since the higher octane will cause it to run richer.
Main thing get rid of the black smoke thats not good
The GC green is fine but would keep the OCI at 5000 miles max.

 

[Thingfish]

Ya,. I will do some more tuning to lean it out.
Yes it has a knock sensor,I log it and it can pull alot of timing at will. Yes I run leaner on c-16.
I change the GC @ 3750 ( the severe service warranty reccomended oci ) It easily classifies for severe, at least under Subaru rules. ( ultra hot ambients, incredibly dusty )

 

[RH+G]

Are U running a stock turbo? Why are you running it at 10.5:1. Thats dirty rich. 11.5:1 is mucher cleaner and better 4 da motor.

 

[forcedtalon]

What we do in the DSM world is tune for low knock. Anything above 7 counts it pulls timing.
Usually when you hit knock up top indicates a lean condition.
I would start to try leaning it out and see what happens with the knock if it gets worse then richen it up but with black smoke out the exhaust I highly dought it. Leave it were it sees light knock thew out the pull. 20- 22* of timing on a third gear pull is what we shoot for on pump.
I also keep the same type of pump fuel in the tank what ever you like shell,mobil or BP pick one and stick with it as well as your race fuel.
Also try not using the MMO for a wile as it will help keeping the knock low. I would recomend not using that.

 

[Thingfish]

It's a 16G evo compressor, 575 cfm or so. 650cc injectors, and a very large Supra pump. ( 255+ lph I believe )
It gets dirty hot here, and the 91 is garbage.
I run into the 12's on race gas. The car likes that a/f in the summer. Egt's stay under 1600f. Inlet temps are within 40f of ambient, unless its a brutal long pull, then it heat soaks and goes up some.

The car was tuned in VERY hot weather,. ( 115+ )
I doesn't knock and I run quite a bit of timing , ( would have to log at it to refresh ). I always use Chevron 91, and either Pro Fuel Mach5 ( 114 unlead ) or c-16 leaded.
I really feel nervous leaning it out, knowing it's going to get very very hot here, and I fear knock with the a/c on. I know it retards on knock,but if it knocks hard it might be over with before it can retard.


Would you believe Subaru's stock maps goes into the 9's ?

 

[forcedtalon]

Do you have an aftermarket fuel pressure regulator? It will be need with that supra pump. If you dont have one you will over run the stocker and run rich.
I have the same turbo ported and cliped.
It may be a good Idea to get a Front mount intercooler since your in such hot temps.
Also tuneing in hot weather requires less fuel since the air is so dry.
I pulled out all that A/C crap to save weight but I can see you needing it in your climate.
Also EGTs really dont tell you alot you can have high EGTs with lean and rich mixture its all in how fast the egts jump a leaner egt would move faster. I would just tune of your wide band.
Also check your plugs. Are they black? If they are then your safe to lean it out. Also you may also want to try 1 range colder spark plug.
Like I said before look into a front mount and will help your knock on the hot days.
What might be happeing as well is when it starts to pull timing your still putting the same amount of fuel in the cylinders and running rich at that point since your timing is so low not being able to burn all the fuel.

 

[Thingfish]

Yes, I have a aftermarket regulator. I run a monster top-mount and have TB inlet temps of about 40f over ambient maximum. ( usually wihtin a few of ambient )
Yes, hot air takes less fuel, but high temps naturally lower octane.
The plugs are already one step colder and read good. They are not black.
And while logging It does not pull timing. According to the IAM ( ignition advance mulrtiplier ) I could ADD timing.

Looking at the exhaust closely while somebody else drove, I see no smoke of any kind. ( thought I did before )