I have a freshly built STi motor that I am breaking in now, using the engine builder's driving recommendations and the recommended Motul 10w40 Break-In Oil (changed after 20 minutes of idle, changed after 250 miles, now on the current oil to complete break-in.
The engine builder recommends a 100-200 mile break in for race motors and a 1500 mile break in for daily driven motors. After that, it says that break-in is complete.
Engine builder's suggested oil is a "high quality synthetic 5w40 oil such as Motul 8100 for street cars or a 15w50 such as Motul 300V for motorsport use."
My question: when do I switch from conventional oil to synthetic oil? I have read here and elsewhere both sides to this and the more you read about oil-related topics, the less you feel like you know when you are done. Is there any conclusive evidence on why or why not to switch to synthetic early? I haven't actually seen that justified with evidence or at least hard data.
I currently have 800 miles on the car and am working on racking the miles up as quickly as I can because I have a tune scheduled for 9 days from now. I will get over 1000 miles for sure by that time but I'm not sure if I'll get to 1500 miles before then. I'm trying to decide if I should just tune on the Motul break-in oil, switch to another 5w40 conventional oil like Castrol GTX, or just switch to synthetic before the tune even if its at 1100 or 1200 miles and not worry about it.
Car is driven in south Florida with a temp range of about 45 degrees during winter nights up to 100 degrees during summer days. Mostly street miles with a few road racing days mixed in each year. Bearing clearances are a hair looser than factory and car should make about 380 whp on 93 octane and about 440 whp on E85.
Also as far as a 5w40 synthetic oil (or even a bit heavier), what do you prefer for a turbo 4 cylinder that is a mix of boring and spirited driving in a hot climate?
On the Motul 10w40 break in oil my hot idle oil pressure is around 22-24 psi now which is good, just not sure if it will dip lower when I start driving the car a bit harder. Oil pressure is around 70-80 psi at 3k to 4k rpm, also good.
The engine builder recommends a 100-200 mile break in for race motors and a 1500 mile break in for daily driven motors. After that, it says that break-in is complete.
Engine builder's suggested oil is a "high quality synthetic 5w40 oil such as Motul 8100 for street cars or a 15w50 such as Motul 300V for motorsport use."
My question: when do I switch from conventional oil to synthetic oil? I have read here and elsewhere both sides to this and the more you read about oil-related topics, the less you feel like you know when you are done. Is there any conclusive evidence on why or why not to switch to synthetic early? I haven't actually seen that justified with evidence or at least hard data.
I currently have 800 miles on the car and am working on racking the miles up as quickly as I can because I have a tune scheduled for 9 days from now. I will get over 1000 miles for sure by that time but I'm not sure if I'll get to 1500 miles before then. I'm trying to decide if I should just tune on the Motul break-in oil, switch to another 5w40 conventional oil like Castrol GTX, or just switch to synthetic before the tune even if its at 1100 or 1200 miles and not worry about it.
Car is driven in south Florida with a temp range of about 45 degrees during winter nights up to 100 degrees during summer days. Mostly street miles with a few road racing days mixed in each year. Bearing clearances are a hair looser than factory and car should make about 380 whp on 93 octane and about 440 whp on E85.
Also as far as a 5w40 synthetic oil (or even a bit heavier), what do you prefer for a turbo 4 cylinder that is a mix of boring and spirited driving in a hot climate?
On the Motul 10w40 break in oil my hot idle oil pressure is around 22-24 psi now which is good, just not sure if it will dip lower when I start driving the car a bit harder. Oil pressure is around 70-80 psi at 3k to 4k rpm, also good.
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