Valvoline Vr1 20w50 still the recommended choice?
#31
Three Wheelin'
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OP - I drive my car year round and the temperature range is similar to yours in your driving months. Might hit the 30s once in a while in deep winter and goes to mid 110s in summer. Freshly blended dinosaur, 20W-50 Pennzoil all year. As long as the oil has the SN mark on the bottle, it's fine.
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#32
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been using Castrol GTX 20w50 and i am more than please with it. i use it in my RX-7's and my 944.
#34
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Used to be a 5w50 oil available (castrol?), back when I was doing this
Now I do what theiceman mentions below
Now I do what theiceman mentions below
#35
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As I've read here, there are opinions that M1's formula has changed for the worse over the years.
Not my opinion as I use VR1 and Shell Rotella only..
Some racers have suspected the M1 formula changes resulted in shearing issues at high rpm/high temps.
I love these cars as well..
#36
#37
Three Wheelin'
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Thanks buddy. It seems like both Amsoil and Royal Purple seem to have great reviews for full synthetic oils.
#39
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i ran a batch of RP 20w50 last summer. made nice pressure at oil change time. about 4.9 bar.
that f_cking oil broke down so fast. to utterly pittiful garbage in less than 1,500 miles.
that's what it did in my engine, at least.
M1 0w50 i ran last fall didn't suffer anything close to this problem over 8 k miles..
heeheehee.
run a 0w oil and you'll actually see an added couple of horsepowers on a dynometer.
just the opposite of your 17w53 Amsoil (summer go-to oil).
#40
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You guys should only be running VR1 or Rotella. Pay very close attention to the ZDDP content. Older cars almost require high amounts of ZDDP while most new cars do not, hence why the majority of oil formulas out there have reduced ZDDP, which easily could reduce the 944 engine life. If you need to lighten the viscosity a bit, mix a quart or two of some thinner VR1 in during the winter if you want. Definitely stick to thicker oils with this engine though.
I'm still impressed with people using Brad Penn. I can just feel the dollar bills flying out of the wallet.
I'm still impressed with people using Brad Penn. I can just feel the dollar bills flying out of the wallet.
#41
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I run m1 0w–40, 1000ppm phosphorus and 1100ppm for zinc and a type 4 base. Summer time ill run 5–50 if I can find it (same ppm)
For reference rotella 15–40 is 1100 phosphorus and 1200 zinc. Not missing much running the mobil 1, and I get good low temperature performance out of the 0w. The 5w 50 should be good for the summer temps,
For reference rotella 15–40 is 1100 phosphorus and 1200 zinc. Not missing much running the mobil 1, and I get good low temperature performance out of the 0w. The 5w 50 should be good for the summer temps,
#42
Three Wheelin'
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i ran a batch of RP 20w50 last summer. made nice pressure at oil change time. about 4.9 bar.
that f_cking oil broke down so fast. to utterly pittiful garbage in less than 1,500 miles.
that's what it did in my engine, at least.
M1 0w50 i ran last fall didn't suffer anything close to this problem over 8 k miles..
heeheehee.
run a 0w oil and you'll actually see an added couple of horsepowers on a dynometer.
just the opposite of your 17w53 Amsoil (summer go-to oil).
that f_cking oil broke down so fast. to utterly pittiful garbage in less than 1,500 miles.
that's what it did in my engine, at least.
M1 0w50 i ran last fall didn't suffer anything close to this problem over 8 k miles..
heeheehee.
run a 0w oil and you'll actually see an added couple of horsepowers on a dynometer.
just the opposite of your 17w53 Amsoil (summer go-to oil).