why does bmw require 10w60 ?

[A_Harman]

Originally Posted By: nleksan
For what it may be worth, perhaps little or nothing, I have had a lot of experience with all manner of BMW, and a buddy races his E46 M3 at a lot of events beside me. Car is heavily modified, but it is mostly suspension/brakes/wheels/body as well as intake, CSL headers (no cats), Eisenmann Race exhaust, U/D Pullies, L/W Flywheel, custom dyno tune, etc. ZERO internal engine mods, and with 80k miles on his '06 it gets a lot of driving done and is religiously maintained, obsessively-so even.
At an open track day Summer '10, he had a serious oil problem. He has a very upgraded cooling system (Fluidyne rad, Stewart wp, Samco hoses, Oil Cooler, etc), so despite the 90-95*f weather he should have been fine. Lap twelve, he began getting oil starvation issues, minor at first but he had the pressure completely drop two laps later on a high G turn. Pulls off after limping the second half of the lap, and oil temp was over 320*f! I have never seen an M hit anything like that.
Turns out that with the car recently out of warranty he did his own oil change, and used M1 or PP (cannot recall which) at a 0w40 or 5w40 weight. The oil did not have the film strength needed apparently, and he dumped it right there while I drove him 55mi to the nearest BMW dealership where he grabbed 10qts of the 10w60 and a filter, we drove back and did the change, and he was out lapping that afternoon with oil temps well within range.
He has since added a larger oil cooler and a larger capacity baffled pan, so he is now holding over 11qts of oil, but refuses to use any other oil.

Perhaps it was a fluke or something else was behind it, but I always remember that day whenever someone asks why I need oil temp and pressure gauges in my own car (nice gauges too... Analog and digital displayed concurrently).
This is NOT a slam against any oil, simply an anecdote of the type of condition under which the 10w60 exceeds lower weight oils.


Good story. For a car that is used for track days, oil starvation in long turns is the most likely cause of engine problems. When I ran Watkins Glen in the early-90's in my Corvette, every time I came out of Turn 6 and looked at the oil pressure gauge, it would be coming up from 6 psi, and the low oil pressure light would go out. This is why I recommend an Accusump for cars that have been modified for higher cornering force on road courses. Stiff, lowered suspensions and sticky tires make it possible for cornering forces of ~1.2G's. The thick oil is not needed when the engine is making full power down the straight, it is needed to buy time when oil pressure is lost in the turns.

 

[CATERHAM]

Originally Posted By: A_Harman
Originally Posted By: nleksan
The thick oil is not needed when the engine is making full power down the straight, it is needed to buy time when oil pressure is lost in the turns.

When I tracked my Europa years ago and running the spec' 20W-50 oil, hard right corners often resulted in oil starvation. The solution was overfilling the sump about a pint and topping up every 300-400 miles. But you still did get caught out on occation. A solution to stop the momentary "death rattle" of running on power with no oil pressure was a can of STP. It did work.
A likely apocryphal story regarding STP was that the practice of adding polymer thickers to oil came out of WWII to extend the life of piston engines that lost oil pressure after being all shot up, and thereby increasing the chances of getting back to home.

Obviously running a much thicker oil is not the solution to deal with oil starvation. At best it's a very foolish practice. The only sensible remedy is to solve the oil pick-up problem in the first place.

 

[nleksan]

Originally Posted By: A_Harman
Originally Posted By: nleksan
For what it may be worth, perhaps little or nothing, I have had a lot of experience with all manner of BMW, and a buddy races his E46 M3 at a lot of events beside me. Car is heavily modified, but it is mostly suspension/brakes/wheels/body as well as intake, CSL headers (no cats), Eisenmann Race exhaust, U/D Pullies, L/W Flywheel, custom dyno tune, etc. ZERO internal engine mods, and with 80k miles on his '06 it gets a lot of driving done and is religiously maintained, obsessively-so even.
At an open track day Summer '10, he had a serious oil problem. He has a very upgraded cooling system (Fluidyne rad, Stewart wp, Samco hoses, Oil Cooler, etc), so despite the 90-95*f weather he should have been fine. Lap twelve, he began getting oil starvation issues, minor at first but he had the pressure completely drop two laps later on a high G turn. Pulls off after limping the second half of the lap, and oil temp was over 320*f! I have never seen an M hit anything like that.
Turns out that with the car recently out of warranty he did his own oil change, and used M1 or PP (cannot recall which) at a 0w40 or 5w40 weight. The oil did not have the film strength needed apparently, and he dumped it right there while I drove him 55mi to the nearest BMW dealership where he grabbed 10qts of the 10w60 and a filter, we drove back and did the change, and he was out lapping that afternoon with oil temps well within range.
He has since added a larger oil cooler and a larger capacity baffled pan, so he is now holding over 11qts of oil, but refuses to use any other oil.

Perhaps it was a fluke or something else was behind it, but I always remember that day whenever someone asks why I need oil temp and pressure gauges in my own car (nice gauges too... Analog and digital displayed concurrently).
This is NOT a slam against any oil, simply an anecdote of the type of condition under which the 10w60 exceeds lower weight oils.


Good story. For a car that is used for track days, oil starvation in long turns is the most likely cause of engine problems. When I ran Watkins Glen in the early-90's in my Corvette, every time I came out of Turn 6 and looked at the oil pressure gauge, it would be coming up from 6 psi, and the low oil pressure light would go out. This is why I recommend an Accusump for cars that have been modified for higher cornering force on road courses. Stiff, lowered suspensions and sticky tires make it possible for cornering forces of ~1.2G's. The thick oil is not needed when the engine is making full power down the straight, it is needed to buy time when oil pressure is lost in the turns.


Thanks for your input!
The car I was talking about, my friend's M3, is a very heavily modified "street car" that is more at home on the track than the street, especially considering the remote reservoir 4-way adjustable Ohlins coilover suspension and combination of genuine M3 CSL ceramic-coated tubular headers, no cats, and Eisenmann "Race" header-back exhaust and test pipe (plus the CSL-inspired full carbon fiber intake and manifold with all 6 throttle bodies bored a few mm's). It is very stiff and very loud! I am very jealous of my friend, as you can imagine.
Consequently, he has a (very nice) set of 18" Kinesis wheels he uses for the track wrapped in R-compound tires (Toyo R888s I think, at the time). So while there is nothing in the car to measure lateral G forces, 1.2g seems completely feasible based on my experience behind the wheel. There is no doubt that this is what caused the oil issues, as it was a long sweeper followed by chicanes that induced the lateral load resulting in oil problems.
I do know that the car was running perfectly for the couple hundred miles prior to the track day, and I assisted with the oil change so I can verify that the car was running with the proper amount of oil. I did forget to mention that he has a catch can installed, but I have never seen those cause problems. Due to the oil cooler installed at the time, it actually had more oil in it than a "regular" S54-powered car. The car burned no oil, it never had before and it never has since, so I am about 90% sure that the oil level was proper. Of course, I am human and I make (plenty of) mistakes, so I can't rule it out...

I personally think that the M1 was too low weight compared to the TWS10w60 and thus did not have adequate film strength to compensate for the momentary high-G-induced turn.
This opinion is backed by the fact that once the 10w60 was reintroduced, the oil starvation issue was not present (or it was so momentary that the film strength of the heavier oil compensated). It is not something that could be easily reproduced as he now has the larger-capacity baffled oil pan and larger oil cooler. The oil pump is, to my knowledge, the OEM one from BMW however, so do you think that upgrading this pump would be a wise move as far as future prevention goes? Now that it is winter, it is modding season for him so it would be easy...

 

[CATERHAM]

A momentary drop in oil pressure has nothing to do with an oil's film strength or the oil's viscosity, it's simply a lack of oil.

It's easy to misread an oil level, I've made the mistake a number of times. Besides I've learned it doesn't really matter, particularly in a car modified to give much more grip, any drop or fluctuation in OP while cornering (or braking as is the case with my Caterham) you add more oil in 100ml increments (to minimize the possibility of oil aeration) until solid OP is restored at that particular corner or corners on the track.

 

[dailydriver]

Originally Posted By: nleksan
Originally Posted By: A_Harman
Originally Posted By: nleksan
For what it may be worth, perhaps little or nothing, I have had a lot of experience with all manner of BMW, and a buddy races his E46 M3 at a lot of events beside me. Car is heavily modified, but it is mostly suspension/brakes/wheels/body as well as intake, CSL headers (no cats), Eisenmann Race exhaust, U/D Pullies, L/W Flywheel, custom dyno tune, etc. ZERO internal engine mods, and with 80k miles on his '06 it gets a lot of driving done and is religiously maintained, obsessively-so even.
At an open track day Summer '10, he had a serious oil problem. He has a very upgraded cooling system (Fluidyne rad, Stewart wp, Samco hoses, Oil Cooler, etc), so despite the 90-95*f weather he should have been fine. Lap twelve, he began getting oil starvation issues, minor at first but he had the pressure completely drop two laps later on a high G turn. Pulls off after limping the second half of the lap, and oil temp was over 320*f! I have never seen an M hit anything like that.
Turns out that with the car recently out of warranty he did his own oil change, and used M1 or PP (cannot recall which) at a 0w40 or 5w40 weight. The oil did not have the film strength needed apparently, and he dumped it right there while I drove him 55mi to the nearest BMW dealership where he grabbed 10qts of the 10w60 and a filter, we drove back and did the change, and he was out lapping that afternoon with oil temps well within range.
He has since added a larger oil cooler and a larger capacity baffled pan, so he is now holding over 11qts of oil, but refuses to use any other oil.

Perhaps it was a fluke or something else was behind it, but I always remember that day whenever someone asks why I need oil temp and pressure gauges in my own car (nice gauges too... Analog and digital displayed concurrently).
This is NOT a slam against any oil, simply an anecdote of the type of condition under which the 10w60 exceeds lower weight oils.


Good story. For a car that is used for track days, oil starvation in long turns is the most likely cause of engine problems. When I ran Watkins Glen in the early-90's in my Corvette, every time I came out of Turn 6 and looked at the oil pressure gauge, it would be coming up from 6 psi, and the low oil pressure light would go out. This is why I recommend an Accusump for cars that have been modified for higher cornering force on road courses. Stiff, lowered suspensions and sticky tires make it possible for cornering forces of ~1.2G's. The thick oil is not needed when the engine is making full power down the straight, it is needed to buy time when oil pressure is lost in the turns.


Thanks for your input!
The car I was talking about, my friend's M3, is a very heavily modified "street car" that is more at home on the track than the street, especially considering the remote reservoir 4-way adjustable Ohlins coilover suspension and combination of genuine M3 CSL ceramic-coated tubular headers, no cats, and Eisenmann "Race" header-back exhaust and test pipe (plus the CSL-inspired full carbon fiber intake and manifold with all 6 throttle bodies bored a few mm's). It is very stiff and very loud! I am very jealous of my friend, as you can imagine.
Consequently, he has a (very nice) set of 18" Kinesis wheels he uses for the track wrapped in R-compound tires (Toyo R888s I think, at the time). So while there is nothing in the car to measure lateral G forces, 1.2g seems completely feasible based on my experience behind the wheel. There is no doubt that this is what caused the oil issues, as it was a long sweeper followed by chicanes that induced the lateral load resulting in oil problems.
I do know that the car was running perfectly for the couple hundred miles prior to the track day, and I assisted with the oil change so I can verify that the car was running with the proper amount of oil. I did forget to mention that he has a catch can installed, but I have never seen those cause problems. Due to the oil cooler installed at the time, it actually had more oil in it than a "regular" S54-powered car. The car burned no oil, it never had before and it never has since, so I am about 90% sure that the oil level was proper. Of course, I am human and I make (plenty of) mistakes, so I can't rule it out...

I personally think that the M1 was too low weight compared to the TWS10w60 and thus did not have adequate film strength to compensate for the momentary high-G-induced turn.
This opinion is backed by the fact that once the 10w60 was reintroduced, the oil starvation issue was not present (or it was so momentary that the film strength of the heavier oil compensated). It is not something that could be easily reproduced as he now has the larger-capacity baffled oil pan and larger oil cooler. The oil pump is, to my knowledge, the OEM one from BMW however, so do you think that upgrading this pump would be a wise move as far as future prevention goes? Now that it is winter, it is modding season for him so it would be easy...


If he's having those oil starvation problems with 888s, just wait until he "steps it up" to a set of dedicated track wheels with the likes of Hoosier R6es!!!

(Hint; he'd better convert that S54 to a dry sump!)

 

[45ACP]

Originally Posted By: dailydriver
Originally Posted By: nleksan
Originally Posted By: A_Harman
Originally Posted By: nleksan
For what it may be worth, perhaps little or nothing, I have had a lot of experience with all manner of BMW, and a buddy races his E46 M3 at a lot of events beside me. Car is heavily modified, but it is mostly suspension/brakes/wheels/body as well as intake, CSL headers (no cats), Eisenmann Race exhaust, U/D Pullies, L/W Flywheel, custom dyno tune, etc. ZERO internal engine mods, and with 80k miles on his '06 it gets a lot of driving done and is religiously maintained, obsessively-so even.
At an open track day Summer '10, he had a serious oil problem. He has a very upgraded cooling system (Fluidyne rad, Stewart wp, Samco hoses, Oil Cooler, etc), so despite the 90-95*f weather he should have been fine. Lap twelve, he began getting oil starvation issues, minor at first but he had the pressure completely drop two laps later on a high G turn. Pulls off after limping the second half of the lap, and oil temp was over 320*f! I have never seen an M hit anything like that.
Turns out that with the car recently out of warranty he did his own oil change, and used M1 or PP (cannot recall which) at a 0w40 or 5w40 weight. The oil did not have the film strength needed apparently, and he dumped it right there while I drove him 55mi to the nearest BMW dealership where he grabbed 10qts of the 10w60 and a filter, we drove back and did the change, and he was out lapping that afternoon with oil temps well within range.
He has since added a larger oil cooler and a larger capacity baffled pan, so he is now holding over 11qts of oil, but refuses to use any other oil.

Perhaps it was a fluke or something else was behind it, but I always remember that day whenever someone asks why I need oil temp and pressure gauges in my own car (nice gauges too... Analog and digital displayed concurrently).
This is NOT a slam against any oil, simply an anecdote of the type of condition under which the 10w60 exceeds lower weight oils.


Good story. For a car that is used for track days, oil starvation in long turns is the most likely cause of engine problems. When I ran Watkins Glen in the early-90's in my Corvette, every time I came out of Turn 6 and looked at the oil pressure gauge, it would be coming up from 6 psi, and the low oil pressure light would go out. This is why I recommend an Accusump for cars that have been modified for higher cornering force on road courses. Stiff, lowered suspensions and sticky tires make it possible for cornering forces of ~1.2G's. The thick oil is not needed when the engine is making full power down the straight, it is needed to buy time when oil pressure is lost in the turns.


Thanks for your input!
The car I was talking about, my friend's M3, is a very heavily modified "street car" that is more at home on the track than the street, especially considering the remote reservoir 4-way adjustable Ohlins coilover suspension and combination of genuine M3 CSL ceramic-coated tubular headers, no cats, and Eisenmann "Race" header-back exhaust and test pipe (plus the CSL-inspired full carbon fiber intake and manifold with all 6 throttle bodies bored a few mm's). It is very stiff and very loud! I am very jealous of my friend, as you can imagine.
Consequently, he has a (very nice) set of 18" Kinesis wheels he uses for the track wrapped in R-compound tires (Toyo R888s I think, at the time). So while there is nothing in the car to measure lateral G forces, 1.2g seems completely feasible based on my experience behind the wheel. There is no doubt that this is what caused the oil issues, as it was a long sweeper followed by chicanes that induced the lateral load resulting in oil problems.
I do know that the car was running perfectly for the couple hundred miles prior to the track day, and I assisted with the oil change so I can verify that the car was running with the proper amount of oil. I did forget to mention that he has a catch can installed, but I have never seen those cause problems. Due to the oil cooler installed at the time, it actually had more oil in it than a "regular" S54-powered car. The car burned no oil, it never had before and it never has since, so I am about 90% sure that the oil level was proper. Of course, I am human and I make (plenty of) mistakes, so I can't rule it out...

I personally think that the M1 was too low weight compared to the TWS10w60 and thus did not have adequate film strength to compensate for the momentary high-G-induced turn.
This opinion is backed by the fact that once the 10w60 was reintroduced, the oil starvation issue was not present (or it was so momentary that the film strength of the heavier oil compensated). It is not something that could be easily reproduced as he now has the larger-capacity baffled oil pan and larger oil cooler. The oil pump is, to my knowledge, the OEM one from BMW however, so do you think that upgrading this pump would be a wise move as far as future prevention goes? Now that it is winter, it is modding season for him so it would be easy...


If he's having those oil starvation problems with 888s, just wait until he "steps it up" to a set of dedicated track wheels with the likes of Hoosier R6es!!!

(Hint; he'd better convert that S54 to a dry sump!)


I think we just disproved Dr Haas's theories in this post.

fwiw, i would totally have been thinking 0W-40 was ok with a car like that.

 

[nleksan]

Originally Posted By: CATERHAM

A momentary drop in oil pressure has nothing to do with an oil's film strength or the oil's viscosity, it's simply a lack of oil.

It's easy to misread an oil level, I've made the mistake a number of times. Besides I've learned it doesn't really matter, particularly in a car modified to give much more grip, any drop or fluctuation in OP while cornering (or braking as is the case with my Caterham) you add more oil in 100ml increments (to minimize the possibility of oil aeration) until solid OP is restored at that particular corner or corners on the track.




I appreciate the input, but I should add that the oil was checked by at least five of us, by dipstick, about 10-12min after he pulled over, without telling the others what it was so not to skew results. Conclusion: oil level was exactly 3/5inch above the Full mark. The distick was wiped clean between each inspection. Also, it was emptied into a clear oil disposal tank that has marking lines in both metric and "American" (lol). The car drained only about .3qt less than was put in, which is within the margin of error considering that not all the oil will drain with just gravity.
In the end, I am confident that this issue was not a result of improper oil fill. It was above the factory level even with an added oil cooler. It was improper oil that was used for the application, especially under racetrack conditions.


Regarding the tires: he is now running the Pirelli dry weather R compound "semi slicks" (three or four grooves down the center of each tire I believe), as they are the closest to full slicks he can run without being bumped up a class, one in which he could not be competitive (911 GT3 is the most used car in the next class up... )

 

[A_Harman]

Originally Posted By: nleksan
The oil pump is, to my knowledge, the OEM one from BMW however, so do you think that upgrading this pump would be a wise move as far as future prevention goes? Now that it is winter, it is modding season for him so it would be easy...


It depends on if the upgrade oil pump is regulated for higher pressure than the stock one, or has larger displacement and is regulated to the stock oil pressure. I'm not a fan of increasing oil pressure because the pump will just pull oil from the pan faster, but if nothing has been done to increase the rate that oil drains to the pan, oil starvation in the turns may become worse. Increasing the oil pan sump volume would be good. Or plumbing in an Accusump would be better.

 

[A_Harman]

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2188539#Post2188539

Also relevant to this discussion is a post I made about a year ago showing how oil pressure in my Corvette fluctuates during a lap at Calabogie. The 'vette has a problem with long left-hand turns. This is why I can't give a simple answer to the question: "How much oil pressure does your engine run?"

Since then, I have switched from Castrol GTX to Mobil 1, and the oil pressure is better. I also have fresh data from Sebring including lateral G's that I may get around to posting sometime.

 

[CATERHAM]

Originally Posted By: 45ACP
Originally Posted By: dailydriver
Originally Posted By: nleksan

I think we just disproved Dr Haas's theories in this post.

fwiw, i would totally have been thinking 0W-40 was ok with a car like that.

A 0W-40 like M1's is perfectly fine if the oil temp's are contained. It is a very common oil choice for E36 and E46 Bimmers at the track, M3 or otherwise.
Due to it's high 185 VI it's a very practical oil at most track day events since most drivers don't have the patience to wait
for the oil to come fully up to temperature before extracting full performance from their cars. And since most track sessions are no longer than 20 minutes high oil temp's are not often a problem even on a hot day.

Ali Haas' theories have not been disproven in the slightest.
Driving high performance cars on the street simply cannot generate the oil temp's that you can on the track.
He never sees oil temp's in excess of 100C in any of his cars and the Enzo max's out at a rather tepid 82C.

 

[dailydriver]

Originally Posted By: nleksan
Regarding the tires: he is now running the Pirelli dry weather R compound "semi slicks" (three or four grooves down the center of each tire I believe), as they are the closest to full slicks he can run without being bumped up a class, one in which he could not be competitive (911 GT3 is the most used car in the next class up... )


Are these the Corsas, or is it something much newer and stickier?? (I'm not that familiar with Pirelli's comp tires.)

Either way, they have to be stickier than the R888s, since even the Corsas were/are a 60 treadwear, and the Toyos are 100 treadwear (some actually consider them a very grippy, summer ONLY street tire, which is what I am considering them for next).

Now your friend's high g loading oil starvation problem makes even more sense.

 

[mpow3r]

Originally Posted By: A_Harman
Possibly. You would have to compare the CCV specs of other 10w60's to determine that.

Here in the USA, we tend to be anti-Castrol because their product data sheets don't give actual tested values, they only say that the oil meets the minimum specs. We have to search the European websites if we want to find actual values.


Thank you jaj, caterham, Doug.. for your input and for clarifying.

Harman, all other 10W60 are around 7000 mark. Is this the spec sheet you are referring to that isn't available to you guys?

Castrol Edge 10W60 specs

 

[nleksan]

Originally Posted By: dailydriver
Originally Posted By: nleksan
Regarding the tires: he is now running the Pirelli dry weather R compound "semi slicks" (three or four grooves down the center of each tire I believe), as they are the closest to full slicks he can run without being bumped up a class, one in which he could not be competitive (911 GT3 is the most used car in the next class up... )


Are these the Corsas, or is it something much newer and stickier?? (I'm not that familiar with Pirelli's comp tires.)

Either way, they have to be stickier than the R888s, since even the Corsas were/are a 60 treadwear, and the Toyos are 100 treadwear (some actually consider them a very grippy, summer ONLY street tire, which is what I am considering them for next).

Now your friend's high g loading oil starvation problem makes even more sense.

Hey, actually I am not sure which exact tire they are (or if he's even still running them... you know how fast track tires can, uh, "disappear"..).

Oh, are you talking about the "P Zero Corsa 'System'"?? If so, I bought those from TireRack once because it had a lower-treadwear rating and everyone commented that it was an extremely stiff and sticky tire that could be used on the road without problem.
Imagine my surprise when they show up and I have 2 not-quite-R-Compound tires and 2 VERY MUCH R-Compound tires... lol. If those are what you're talking about, then no, my buddy hasn't run them, but I have... Outshine the PS2's on the street, but it's not really a fair comparison... They were significantly less comfortable; compared to 245(f) and 275(r) Pilot Sport 2's, the "Corsa System" tires at 255(f) and 275(r) exhibited almost zero sidewall flex under any street condition, were sticky enough that they could overpower the ABS at maybe 3/4ths braking pressure, but gave me TOO much confidence on the road I think...
So, I went back to real street tires for the street. Plus, they only lasted about 6k miles (granted, they were not easy miles hehe). In all honesty, for the money, I liked the P Zero Rosso's better; although I really want to try the new "PZERO" (no "Rosso" or "Corsa" or anything following it), as it is supposed to compete with the new Pilot Super Sports, with which I've fallen in love

Man, sorry for getting off track... blah. Not only am I still waking up, but tire names end up confusing me regardless

Looking at various tread-pattern pictures, I am pretty sure now that he was indeed running the P-Zero Corsa tires... The ones that have a tread pattern of what looks like a bunch of very-elongated "S"s alternating from left to right... http://tinyurl.com/6o6fkgy

The "Corsa System" tires that I ran are these: http://tinyurl.com/856gkyx (the more "aggressive" ones going in the rear, with the skinnier, more-tread-laden ones in front).

This next summer, I think I am going to go out of my "comfort zone" and start trying other tires on the track besides the usual MPSC's for R-Compound and MPSSs/MPS2s/PPZs for "Street Tire Only" events...
Any suggestions? You seem to have quite a bit more knowledge than myself when it comes to tires? I don't want to derail this thread, so feel free to PM me if you'd like (and moderator/s, please let me know if I am straying too off-topic).
I would basically like suggestions for the following:
- HDPE/Road Course: R-Compound Tires
- Autocross: R-Compound AND "DOT Street Compound" UHP Tires
- Road Course: "DOT Street Compound" UHP Tires

Thanks!

 

[dailydriver]

Yes, those ARE the 'Corsas' (the first link) which I was referring to.

They are in between the '100 treadwear class' tires (Toyo R888/RA-1, Nitto 555R2/NT-01), and the full-on 50/40-0 treadwear 'R' compound tires (BFG R-1, Hoosier A/R 6, Kumho V710, Ventus Z214, etc.), and about the equals of the 80 treadwear rated Michelin Pilot Cup tires (as far as 'stickiness' goes).

Expect the Corvette Z06/ZR1 to re-write the Nordschleife lap record once equipped with the Pilot Cups.

 

[nleksan]

Originally Posted By: dailydriver
Yes, those ARE the 'Corsas' (the first link) which I was referring to.

They are in between the '100 treadwear class' tires (Toyo R888/RA-1, Nitto 555R2/NT-01), and the full-on 50/40-0 treadwear 'R' compound tires (BFG R-1, Hoosier A/R 6, Kumho V710, Ventus Z214, etc.), and about the equals of the 80 treadwear rated Michelin Pilot Cup tires (as far as 'stickiness' goes).

Expect the Corvette Z06/ZR1 to re-write the Nordschleife lap record once equipped with the Pilot Cups.

Ahh, okay. I suppose either I was misinformed about the tires, or I misunderstood. I was going to say, they looked an awful lot like the "Corsa System" rear tires I had, but I no longer had them at that point so I could only go by memory (and Pirelli tends to make tire treads that look very similar to one another, IMO).

Personally, I liked the amount of rear grip those tires gave me; I would say it was comparable to the Pilot Cups on a dry surface with a 3500rpm launch (don't need to rev high for a launch with a twin-screw supercharger; peak torque begins at 1500rpm). Even with the power my car puts down, those tires DID grip like crazy. With a 3500rpm launch, I would NEVER get traction with a UHP All-Season tire (tried my friend's to prove it), and my PS2's/PSS's/PZERO's/etc all tend to lose a few layers of rubber on that kind of launch; at least based on the two lines following me.
Pilot Cups AND the Corsa's (which I apparently had in the rear) take that same kind of launch like a champion. They do nearly as well as the BFG R1's, despite having double the tread-wear rating. Now, the BFGoodrich R1's, Kumho Ecsta V710's, Toyo RA-1's, and Nitto NT01's all grabbed harder, especially getting on the throttle hard through a turn (or even during a turn; I find all four of those tires to have amazing predictability when it comes to traction; if you're gonna slide, they're gonna let you know multiple times), but also during a hard launch. In fact, while I have never tried, I wonder if I even COULD keep any of those tires spinning indefinitely? Based on how quickly they grab, ESPECIALLY once up to temp, I think that they would indeed grip before too long. And this is with over 430rwhp. I can't even imagine what it would be like to put some V710's on an EVO8/9 or STi, properly modified to put about about 390-400ALL-WHEEL horsepower, and launch at ~4500-5500rpm with the boost gauge pegged... I'm not big on AWD, but I have to admit that the ones I have driven launch like crazy; but I find it takes more skill to launch a RWD car

plus, RWD doesn't break on a hard launch like AWD does.

In my opinion, anyway.

 

[A_Harman]

I cringe every time I hear someone talking about launching an AWD car hard. I keep remembering that early GTR's ended up with split transmission cases when people did too many of them. Nissan eventually started saving the number of Launch Control occurrences in the ECU to get a handle on the problem.

I used to run 100 treadwear tires on the Camaro. I think I went through 3 sets of Nitto 555RSII's, and 1 set of Toyo RA1's. I would buy them new in the spring and run track days through the summer. The tires became slicks by then. By the time I got to October, I would plan which vehicle to drive by checking the weather forecast and left the Camaro at home if it was going to rain.

The last couple of years, I ran Kumho Ecsta XS tires, which are 180 treadwear. I thought they were going to be slippery rocks, but found that in the dry they were very fast, and I was able to hang with people on 100-treadwear tires in the turns. These tires wear long enough that I can get through driving season and still have enough tread to drive them on the street in the rain. This year, Tire Rack was back-ordered on Ecsta XS's, so I ended up with a set of Nitto NT05's at 200 treadwear. I think they give up a little speed to the Kumho in the dry and are not as good on the street in the wet.

 

[virginoil]

From 10w60 to tread-wear on tires ????

Off track !!

 

[nleksan]

Originally Posted By: virginoil

From 10w60 to tread-wear on tires ????

Off track !!


Not if you have good tires

 

[dailydriver]

Originally Posted By: virginoil

From 10w60 to tread-wear on tires ????

Off track !!


Yes, sorry!

But as nleksan says, high g-loading CAN effect oil/oiling systems, and determine which weight to be used.

 

[demarpaint]

Originally Posted By: Brenden
CAFE mandates certain emissions to meet and MPG numbers, BMW cares about neither with the M cars, their focus is not on pleasing the tree huggers, but for real drivers with those cars, they pay the fines and produce them anyway.

The reason cars use such light weight oil here in the USA is to wring every last MPG out of the engine they can, cars that are recommended to use a 5w20 here will ask for 10w40 in Australia because they do not have CAFE requirements so they don't have to stretch 1.2% (if that) better fuel economy out of the car.

The average M car has the HP of 4 of my Honda's, and weigh only slightly more...


What happens to the old man US car buyer that buys and uses it to go to Church on Sunday in the winter in cold Northern US climates? I bet 10W60 isn't the oil to use for that situation, in fact a 0W40 or thinner might make that engine last a whole lot longer. JMO