Oil Viscosity Recommendation on modified application..........
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Le Mans Master
Joined: Jun 2004
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From: The Arid Sunny Desert
Oil Viscosity Recommendation on modified application..........
I have been running Redline 5W-30 Synthetic oil since I've owned my car. In addition to my heads/cam package (which I've had for 6 years), I am now adding a supercharger. Redline makes a 5W-40 and a 10W-40 fully synthetic oil. Is the 5 weight oil superior since it flows better than the 10 weight when cold? I drive the car all year round including in the very cold weather so my next oil change after this one would most likely be in the springtime. Thanks.
Burning Brakes
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From: Granville Ohio
St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16'17-'18-'19-'20-21
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Yes, among a manufacturer's various blends, the lower "cold" viscosity will allow your oil to pump up faster during startup, even at 70 degrees F. If your engine's bore and component tolerances were unchanged (or are better than stock), then you shouldn't have to worry about using a thicker "cold" oil. If you're concerned about oil temps above 260F, at least one manufacturer makes 0W-40 oil (Mobile). This oil is factory fill in Porsche Boxsters, I believe.
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Le Mans Master
Joined: Jun 2004
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From: The Arid Sunny Desert
Originally Posted by dcblackc5
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From: Winston-Salem North Carolina
St. Jude Donor '08-'09
I noprmally run the extended mobil 1/Amsoil 5w 30. for track I change to Amsoil15w50, up at Watkins Glen last month I used mobi1 and the oil temps got to 305*
