Can I get a recommendation?

[froggy47]

1996 Vette LT4 engine 55k miles living in San Diego (no cold starts below 45 degf). High temp can be 90 plus degrees & autox racing 2x month. Oil temps have seem 300f on a hot race day but not prolonged. Maybe 1/2 hr to 45 min for 4 runs.

Been using Mobil 1 10w30.

I was wondering about 5-30 fo winter where temps are more 65-75 on hot days. Still would autox and oil temp could get to 230 - 240.

Many thanks. Will provide more details if needed

 

[XS650]

You're being little rough on your oil, Froggy

The occasional 300F oil temp definitely calls for something more than an xW-30.

At least a good xW-40 synthetic, more likely an xW-50.

With your climate your have no reason to use a 5W-xx, shouldn't hurt as long as you use a first class synthetic, but there is no reason for it. If you need a 5W-xx in San Diego, then the upper Mid-West and GWN contingants need a -50W-xx.

You're a good candidate for an oil cooler. There have been a couple of interesting threads lately with info on some real compact oil to water heat exchangers that mount between the filter and the block. They are only about as big around as the filter and 2 or 3 inches long.

Are you running your fans full time on the track?

 

[jsharp]

I agree with XS650. An oil cooler is in order and probably heavier oil. What kind of water temps does the car run with 300 degree oil temps? The oil to water heat exchangers are slick but I wonder if the car has enough radiator capacity? If your water temps are also high you'll only make them worse with a oil to water exchanger. I think I'd be looking into a large oil only cooler...

 

[John_E]

In what part of San Diego County do you live? One of my coworkers is pretty active in the north coast Corvette club, and I have an 88-years-young friend who recently bought a new Corvette for "one last fling." (He has owned various sports cars over the years, but I kid him about his "midlife crisis toy.") He chose the Corvette because it was the only sports car large enough to hold two people and his 'cello.

At your peak oil temperatures, you may well need a 40-weight synthetic oil. I am running Mobil 1 0W-40 in my 2001 Passat. I know I don't need the "0W" pourability, but 0W-40 is the only weight of Mobil 1 with the VW 502 seal of approval, and I have already needed my powertrain warranty once, so I need to keep it in force!

 

[Gene K]

Redline 10W-40.... It excels at that kind of use.

A cheaper alternative is Mobil 1 T&S 5W-40 (It is more stable than the 0W-40).

I would even prefer a Group III like Castrol Syntec 10W-40 to the current oil for temps over 240&#176F

Gene - Previous 1996 LT4 Owner

 

[427Z06]

quote:

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Originally posted by Gene K:
Redline 10W-40.... It excels at that kind of use.

---

I concur. I'd also would give serious consideration to an oil cooler. A used oil analysis would probably be a wise investment too. Here's a service I and many recommend.

 

[Patman]

I would recommend German Castrol 0w30, Mobil 1 0w40, Mobil 1 5w40, Amsoil 5w30, Amsoil 10w30, or Royal Purple Racing 41. Castrol Syntec 5w40 should also work well.

I run the German Castrol 0w30 in my 1998 Corvette.

 

[Gene K]

quote:

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Originally posted by Patman:
I would recommend German Castrol 0w30, Amsoil 5w30, Amsoil 10w30....

I run the German Castrol 0w30 in my 1998 Corvette.

---

Patman while I really like the GC I really can not in good conscience recommend a oil with a 3.45-3.6 HT/HS for oi temps that sometimes exceed 300&#176F combined with extreme stress on the road course.

The GC would be a good choice if the owner was willing to change before going to the track.

I am somewhat worried about the viscosity retention of the Mobil 1 0W-40 as well.

Gene

 

[Patman]

quote:

---

Originally posted by Gene K:

quote:

---

Originally posted by Patman:
I would recommend German Castrol 0w30, Amsoil 5w30, Amsoil 10w30....

I run the German Castrol 0w30 in my 1998 Corvette.

---

Patman while I really like the GC I really can not in good conscience recommend a oil with a 3.45-3.6 HT/HS for oi temps that sometimes exceed 300&#176F combined with extreme stress on the road course.

The GC would be a good choice if the owner was willing to change before going to the track.

I am somewhat worried about the viscosity retention of the Mobil 1 0W-40 as well.

Gene

---

True, with sustained 300F temps, an oil with around 4.0 HTHS might be better. Although the best route to take would be to run an oil cooler, keeping the oil temps below 250F.

No matter what oil he finally chooses, I think getting a few used oil analysis done is definitely in order here. When you race your car hard it's even more vital to make sure you choose the right oil for the application.

 

[buster]

I'd even go as far to say Mobil 1 15w50.

 

[Motorbike]

Synergyn 3w-30 or Mobil 0w-30R for that one .

This is the type service those oils were made for , it just happens they will go long n far in the daily drivers too .

 

[froggy47]

Thanks for the posts, I had no clue this board was so active.

I'm at the end of a "top end" cleaning (GM additive in the tank) which results in some carbon & crap finding it's way to the oil so I'll be doing an OC soon, hence the post.

The Mobil 1 I use is Full Synthetic, yes?

The oil cooler is a great idea but not an option in my "stock" class - it would bump me into a class that allows lot's more mods than I currently have.

As I understand the history of the Vette the oil cooler was dropped when GM switched the oil recommendation to M1 Full Synthetic as it's supposed to handle the higher temps & dropping the cooler dropped wgt.of the car.

Water temps are 215 to 230, in normal crusing oil runs about the same or maybe 5 or 10 deg. higher. Only on race days (with some redline runs - 1st & 2nd gear) does it get to 250 - 300 range. Those water temps are considered good/normal for this car. Some guys will try to get the LT engines to run cooler but most of the "experts" I trust say that's not necessarily a good thing to run this engine too cold. The optimum target temp for oil for good life/performance seems to be at 240 deg F

My race club is SCCA San Diego region, cruise/wax club is North Coast Vettes.

I'm on extended warranty so need to stick close to factory/dealer recommendations so I'll have to stick with Mobil 1. I know the other's are "approved" and meet oem spec etc. It's just easier to show a receipt for M1 and not have to "educate" a service writer at the dealership.

It's seems I won't go wrong with a Mobil 1 multi that goes to x- 40 so I'll look fo that. Also is that 0w30R a "Race" oil that is ok to use on the street.

That also might be a good choice as I don't change oil specifically for race day vs. street. This is autox, not track or wheel to wheel racing so the cars tend to be street driven to the event (although we do have some that come on trailers)

Again thanks if you follow up re: this extra info

 

[Gene K]

M1R is a race lube but its okay to use on the street. It has a much more robust additive package than standard M1. It also seems to have more Group V than the normal M1 formula. It is generally only available by mail order from companies such as avlube.com.

It still has a low HT/HS but hopefully at 300&#176F the extra additive package would protect the engine. As stated earlier it would be nice to see a HT/HS closer to 4.1 than 3.1. It still seemed to do okay at the Daytona 24 hour.

At anything under 260&#176F the 5w30 is fine.

Gene

 

[froggy47]

Thanks Gene