Oil choice for highly modified Japanese turbo 4cyl

Messages
1
Location
Denver, Colorado
So guys and gals, I'm looking to step into some engine oil a little higher quality than the Rotella T6 I've historically used on my car. The car is a turbocharged Japanese 4 cylinder and runs anywhere from 15 to 25 psi of boost, up to 8,000rpm, and will see sustained high load driving (road course, autox, canyon carving) as well as street driving. It is a highly modified engine, bored larger than stock with all forged internals. It is not a daily, and I'm happy to shell out more for top quality oil simply because it's cheap insurance. Ideal oil weight is probably 40, but I might consider a 50 weight for any track time it will see in 90*+ weather depending on what clearances I end up running. I would like to run full synthetic, and the car never sees more than about 250* oil temps, typically sitting in the 200-220* range thanks to a very large oil cooler. I change oil after almost every track event. The primary reason for looking to upgrade the oil that I run in this engine is that it is currently torn down being rebuilt after finding some excessive bearing wear. While basically any old synthetic oil in the right viscosity *should* be fine for my uses, given the nature of the car and the fact that it's currently torn down to rebuild after some accelerated wear, I simply want to fill it with whatever is objectively the best oil I can. The engine sees some excessive forces well beyond what the manufacturer intended - MUCH higher cylinder pressures (the engine makes 3-4x the power of a stock example), higher RPM, a turbocharger, alcohol based fuels, sustained high load+high temp driving, etc. Some oils are certainly going to be more up to the task of dealing with this than others. This is the third time this engine has been out, and I'd really like it to be several years and many thousands of miles before it has to come out again smile If I end up paying a decent bit more for oil changes with a marginal improvement in engine protection, that peace of mind is worth it to me to shell out for something like Amsoil or Schaeffers. I'm considering options such as LiquiMoly, Motul, Schaeffers, Redline, and Amsoil but I am certainly happy to add other options to that list. I'm sure the car would probably be happy with any of those, but I'm hoping to find some rationale that might bring one or two brands or formulas to the forefront of my consideration. Engine protection is my primary concern here.
 
Messages
1,098
Location
TX
I'm guessing any of them would do fine and I doubt anyone can provide concrete, scientific data otherwise. Red Line is what I use in my motors, never had an issue. Certainly interested in hearing the discussion, though!
 
Messages
5,010
Location
VA
Originally Posted by CT8
The engine has some serious mods ,I would ask the builder of the engine.
Agreed. thumbsup
 
Messages
578
Location
israel
in my 550whp sti i used the motul 300v,u cant go wrong with this oil. btw the build quality,right parts and tune is the most important in keeping your engine alive. many oils will do the job but if the engine was assembled bad,or with weak parts and bad tune the engine will die regardless of the oil used.
 
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Messages
8,051
Location
Michigan
If you're having bearing problems, I would look into tightening the clearances. Tighter bearing clearances lead to lower peak film pressures. The highest-end racing engines such as F1 are built with such tight bearing clearances that they are locked up at room temperature and must be preheated to get enough bearing clearance to start. If you are running alcohol based fuels, maybe you are getting excessive fuel dilution, and the oil is thinning. Have you been taking oil samples? Maybe you could find adverse conditions before it leads to real engine damage again. If you have a really good intercooler, I would say stop running the alcohol fuel. I can't remember ever seeing anybody running alcohol fuels in 30 years of track driving. Yes, IndyCar does it, but the engines are designed from the start for it. If you have a really big oil cooler, and oil temp never gets above 250F, you should not need 50-weight oil. 40 should be sufficient. Do you have data logging on the car so that you can see if oil pressure is stable at all points on a race track? Reading between the lines of your post, you have been having repeated bearing failures in short time intervals, and you are using good oil and changing it after almost every event. Maybe your problem is more related to crankcase venting and breathing. The best oil in the world isn't going to protect your engine if it can't get back to the sump to be picked up by the pump to ensure stable gallery pressure. Loose bearing clearances mean higher oil flow, so more oil is flying around the crankcase. High boost pressure means higher crankcase pressure, making it impossible for oil to return by gravity to the sump. What engine and what car are you working on?
 
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Messages
578
Location
israel
many shops uses the t6,like switzer performance which builds some nasty gtr׳s. if its my motor id go with the 300v or redline.(cant get the t6 or penrite oil here which i saw being used in some 2000whp gtrs as well.)
 
Messages
602
Location
The ATL
Originally Posted by avi1777
in my 550whp sti i used the motul 300v,u cant go wrong with this oil. btw the build quality,right parts and tune is the most important in keeping your engine alive. many oils will do the job but if the engine was assembled bad,or with weak parts and bad tune the engine will die regardless of the oil used.
This. I run 300V in my boosted Si (spends A LOT of time above 4500 RPMS) and has never let me down. The inside of the engine is as clean as can be.
 
Messages
77
Location
PA
Are you running an accusump? What oil pan are you running? I'm almost willing to bet if it's not an extra capacity/baffled pan then that's your issue with wiped out bearings. Oil starvation. Also if you have an inadequate PCV/catch can system, at high rpms, all that oil is getting backed up in the head as the crankcase gases are impeding the oil drains in head. Lots of different things can come into play here.
 
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Messages
578
Location
israel
Originally Posted by ka9mnx
Unfortunately with an engine like yours, and driving style, frequent rebuilds are part of ownership.
+1 been thru 3 engine my self,thats the game. build,race,brake,repeat. in general try to use as little boost as possible.
 
Messages
77
Location
PA
I'm on my same engine for over 4 seasons. 850whp, 4 cylinder, 45psi and everything looked fine last time I broke it down for inspection. I run 20w50 vr-1. Engines last if they're built and tuned properly for their intended application. Also what engine are you running and what clearances? Mains/rods, PTW...
 
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Messages
578
Location
israel
Originally Posted by Lasthope05
I'm on my same engine for over 4 seasons. 850whp, 4 cylinder, 45psi and everything looked fine last time I broke it down for inspection. I run 20w50 vr-1. Engines last if they're built and tuned properly for their intended application.
+100
 
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Messages
2,867
Location
pa
real synthetic Ester based oils are the gold standard for sure!! as noted everything must be RIGHT when engines are pushed to extremes. Redline my fav notes a break in with conventional oil when using their real synthetics + they have REAL hard core oils for RACING, no additives for longer drains but extreme zddp etc for the most protection!!
 
Messages
4,597
Location
Manchester, England
Call Redline for a reccomendation on viscosity, and look to a dry sump to negate some of the issues you see with the modifications. Modifying one part of the engine has knock on effects on other areas and your oiling system can't keep up.
 
Messages
2,011
Location
War Eagle
Mobil 1 15w50 is a possibility Great oil with higher level of zinc and not hard to find and not crazy expensive since you change it frequently
 
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