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On average, I track my car 10, twenty minute sessions every two months. These sessions can be on cool 60F degree days and some are on days as hot as 95F degrees. It is my everyday car and I drive on the street about 1000 mile between track events. All tolled, I probably put 6.5K miles on my car all year.

1. Can someone recommend an oil change frequency that will protect my engine?
2. Also, do I really need to change out my high temperature brake fluid after every event or do I just look for on track fade and, if I get some, change out the fluid.

Thanks. I am on track in three days. A quick response would be a timely response.
 

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A "rule of thumb" I was given by a local race shop is to halve the OEM intervals for fluid changes. For example, oil changes every 5k miles instead of 10k miles. Also, consider upgrading oil to something like Liqui-Moly, Redline, or Motul.

For brake fluid, I'd suggest a full flush annually, and a corner bleed every other (or every) event. The corner bleed is just to get fresher fluid back into the calipers. And don't forget each caliper has two bleed valves.
 

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Wow. Just what I needed! So a corner bleed is just take a little out at the corners and not replace the all the fluid. Do I have that right? Is a little a tablespoon or two at each of the eight valves?
 

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Wow. Just what I needed! So a corner bleed is just take a little out at the corners and not replace the all the fluid. Do I have that right? Is a little a tablespoon or two at each of the eight valves?
Yes, that's the idea. I'm not sure the exact capacity of the calipers, but might want to do a little more than a tablespoon or two (maybe 3-4?), at least for the front calipers (which are physically bigger).
 

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First, my two cents is that your brake fluid and engine oil can never be clean enough. They start to deteriorate the minute you start using them.

However, I think changing your brake fluid every event is excessive. It would be interesting to know just how hot the brakes actually get. The 718 GTS has fairly large brakes and my gut tells me they stay relatively cool. Of course this depends also on pad thickness and rotor thickness. I never noticed any brake fade on my car and I have done some heavy AutoX laps ( repeatedly not like a typical AutoX event) and some HPDE on fluid that has hundreds of miles of mountain driving on them. As an other anecdote, Porsche driving school gets at least a whole day of driving it's cars. ( maybe more, I don't know if they change the brake fluid everyday) but on a given day those cars are used continuously for about 5-6 hours ( my guess) on track. So that would be about 15-20 twenty minute sessions. Personally I would be changing my brake fluid every 5-6 event days if it were me and didn't feel any fade. YMMV.

The other issue I have heard is the higher temp brake fluid is more hygroscopic. So there is a trade-off between going to higher temp and longevity of the fluid. I'm thinking about switching back to stock fluid because of this. Having never experienced brake fade I don't really know where my limit is.

Regarding oil...in my experience the 718 GTS runs pretty cool. Much cooler than I would have expected with a turbo and the performance the car offers. I think this is good for the oil longevity. I got the GTS specifically because I wanted the third radiator. It might be interesting to actually send you oil out for testing if you are going to track for a long time. Might be money well spent to get a better profile of your oil. Could pay for itself by giving you peace of mind between extended changes. Once again. if it were my car, I would probably change it every 5 or so events. Maybe in my mind that might be a bit more than necessary but given the use, I wouldn't mind spending the money. I know many people are much more paranoid about changing oil every 3k miles, flushing brakes really frequently, blah, blah blah but I have never been one for wasting money or time because I am paranoid because of something I read on the internet...mostly by some uninformed person with a "cheap insurance" argument.

(Personally I keep my cars a long time and ( knock on wood) my 15 and 20 year old cars are still humming along without major mechanical issues. Yeah...I even have the original IMS bearing in my m96 engine. I'll probably get the "solution" when my clutch needs to be replaced but I expect to get north of 80K miles on a clutch so that may be a while.)

Second, how long are you getting on a set of stock pads? Have you switched to some aftermarkets?

Everything I have said is my opinion and what I do ( although I haven't tracked it as extensively as you.). I have no scientific data to back up any of it. It is my comfort level as a compromise between taking care of the car and not wasting money.
 

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At the risk of making a "cheap insurance" argument, if your brake fluid is degraded enough to the point of failure (i.e. too much water), the result is not simply "brake fade." It's "pedal to the floor, no brakes." It's happened to me on a previous car, the immediately previous braking zone felt fine, and suddenly I had no brakes as I'm trying to reign it in at ~130mph going into a corner (fortunately in that case, I was able to pump the brakes and get some braking back. At which point, I finished the lap as a cool down, and came off track calling it a day).

P.S. You can also look at the "wet" boiling temp of the high temp fluids to get a sense of how they perform after some use. In the Motul line, the RBF600 and RBF660 wet boiling temps are 399*F, compared to 369*F of their regular DOT5.1
 

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I use Castrol SRF on my track cars. It has a wet boiling point of 518 degrees f. No other brake fluid comes close! I change it once a season and have never had any problems. By contrast, I have lost my brakes at close to 150 using other "racing" fluids. The trick there is to change the fluid more often since the fluid loses a lot of performance as it takes on water. While the Castrol isn't cheap, I don't fool around with brakes.
 

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fwiw, I had brakes fail on my 40 year old 911 once when I was a novice DE driver. It was probably from overheating due to inexperience and poor braking technique. I soon switched to Castrol SRF and arguably got better at braking. I never had another issue (up to 4-5 events per year). I changed the fluid annually.

I replaced the stock fluid in my 718 GTS with Castrol GTS before my first DE in the car last May. I only ran 3 or 4 sessions the first day, and my weekend was cut short due to a tire issue. The next DE I will drive in this car is in a few weeks. I may do a couple more
events between then and next May, when I will replace the SRF with more of the same after one year.
 

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i am mostly track with my 718 but i do some street driving as well. after a discussion with my shop owner who preps my car when i can't and the head tech guy at my local dealer who is also a good friend i change my oil every other event. both have told me stories of problems with turbos on 718s, more so on those that are tracked often (the turbos are cooled by air and oil). i have a friend with a '18 CS who has had issues with his turbos after tracking it as well. i look at it as cheap insurance. oil changes, including filter, are around $100 (suncoast sells the filters w/ washer and seal for $24 vs $45 + tax locally) so it is cheap to ensure i have optimal performance for the long haul. while i am smooth i am a fairly aggressive track driver, so my car gets beat on but in a loving way :) i have almost gone down to under 6mpg at the track (around 6.2 so far is my best) but i will get there!

for brakes i change the fluid every 3-4 events (motul 660), typically the same time i have to change the pads and sometimes rotors and bleed them before each event. with the stock equipment i would get 2 events on rear pads, 2-3 events on front and 3-4 on the rotors. i have switched to giro disc 2 piece rotors and their ss pads, which is a nice improvement over stock though i never had any problems with stock other than wear. so far i have done 3 events and they are still around 40% left. my events are typically 3 days (open track day friday, 4 sessions a day and a lot more use than that giving rides to guests and students when i am not out in my run group saturday and sunday) so i drive quite a bit more than most at an event.

sure, some may call my intervals excessive, but to me it is cheap overall and will maintain the longevity and performace of my vehicle. after options my car was approaching $90k, so a $100 oil change is nothing. i don't even bother to count track maintenance costs like brakes and tires because those are heavy wear items and it's the cost of having the fun i want to have.
 

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I use Castrol SRF on my track cars. It has a wet boiling point of 518 degrees f. No other brake fluid comes close! I change it once a season and have never had any problems. By contrast, I have lost my brakes at close to 150 using other "racing" fluids. The trick there is to change the fluid more often since the fluid loses a lot of performance as it takes on water. While the Castrol isn't cheap, I don't fool around with brakes.
You can't get SRF this year! No one has any. I think they either have production problems or aren't allowed to use something in it anymore. It's back-ordered everywhere.
 

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fwiw, I had brakes fail on my 40 year old 911 once when I was a novice DE driver. It was probably from overheating due to inexperience and poor braking technique. I soon switched to Castrol SRF and arguably got better at braking. I never had another issue (up to 4-5 events per year). I changed the fluid annually.

I replaced the stock fluid in my 718 GTS with Castrol GTS before my first DE in the car last May. I only ran 3 or 4 sessions the first day, and my weekend was cut short due to a tire issue. The next DE I will drive in this car is in a few weeks. I may do a couple more
events between then and next May, when I will replace the SRF with more of the same after one year.
I'm a BMW CCA instructor for about 20 years now...

The reason your 40 year old 911's brakes failed is likely because the fluid was several years old and water had leeched into the brake system from the atmosphere over time. Hygroscopic force is incredibly strong. It pulls moisture right through rubber lines...very slowly but surely. When brakes get hot, the water boils and you have compressible steam in your brake lines. If there's enough water boiling (liquid turns to gas, which is compressible), the pedal goes all the way to the floor.

Second.... It doesn't matter that you do several DEs or Autocrosses or none on your fluid. What matters is the age of the fluid, storage conditions of the car and the sort of lines on your brake system.

Teflon braided lines not only make the pedal feel firmer but they're much better than rubber lines at keeping moisture from humidity from the air. It also helps if the car is kept in low humidity conditions.

The heating up of the fluid repeatedly may cause small amounts of moisture in fairly new fluid to boil in the system. Pedal will get a little soft in that situation. That's when you need to bleed the system, not completely change it. If pedal feels fine after a track weekend, there's no need to do anything. Changing annually is usually OK if the brakes are big compared to the car, as on 718s.

If you leave fluid in for many years on a street-only car, water will get in and corrode the inside of the brake components. So long as you don't heat the brakes up, they'll still work until something starts leaking and failing...usually calipers but sometimes the master cylinder.

Also, if you ever do experience a foot to the floor brake failure, pump the brakes repeatedly. Unless it's an old system that has developed a fluid leak, they will come back, hopefully before the car leaves the track.

No matter what, ALWAYS KEEP DRIVING THE CAR until it stops. Don't panic, let go of the wheel, close your eyes, look at your instructor or look at the brake pedal. Keep your head up, look around and try to find the least damaging area to steer to if you're off. If not, pump and look where you want the car to go. You can also try downshifting to slow it down. Most bad damage to cars on track can be avoided by a smart recovery. As you get faster, you need to think about this Plan B stuff as well as practicing alternate lines through corners.

I had a student who downshifted right at the brake zone of Turn 1(end of main straight) on the 3rd lap of his first session with me. I was very concerned about why. When he told me his brake pedal went to the floor. When I found out what had happened, I was pretty happy with what he did.

His car was an old BMW 2002 that he and his father had prepped for this track day. They have small brakes and the fluid was 5 years old. We went in right away. He and dad got some new fluid and changed it. We resumed on the next session. He was a great student, on of the best I ever had, but that first session shook us both a bit. By the 2nd day, I had him passing most of the field of newer, faster cars....and safely.

:)
 

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My theory on oil is that it lasts a lot longer if you don't get the car real hot at a track day. I change AFTER every track weekend. If I've been driving it easy and without a lot of cold starts, I'll keep oil in with as much as 4000 miles before a track event. When I get home from tracks, even if I just changed, I'll change again. The additives degrade pretty badly if the engine gets very hot. With mid-engine cars, the engines get hot. 718 has electric fans that keep running but my '06 Cayman S didn't have these. I would do laps around the parking lots for 5 minutes or more AFTER cool-down laps to circulate air before shutting down.

Another factor for turbos is that you don't want to shut off the car immediately after high RPMs. This is because the oil stops circulating when you shut down, but the turbo is still spinnning. This can cause it to spin on dry bearings and that's horrible for turbo life.

718 may have one or more pumps keep moving oil after the ignition is turned off. There is certainly plenty of activity going on under there after I turn my 718CGTS off. Fans for sure, but maybe more?

:)
 

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I'm a BMW CCA instructor for about 20 years now...

The reason your 40 year old 911's brakes failed is likely because the fluid was several years old and water had leeched into the brake system from the atmosphere over time. Hygroscopic force is incredibly strong. It pulls moisture right through rubber lines...very slowly but surely. When brakes get hot, the water boils and you have compressible steam in your brake lines. If there's enough water boiling (liquid turns to gas, which is compressible), the pedal goes all the way to the floor.
:)
The brake fluid was replaced within a month of my first DE.
 

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Another factor for turbos is that you don't want to shut off the car immediately after high RPMs. This is because the oil stops circulating when you shut down, but the turbo is still spinnning. This can cause it to spin on dry bearings and that's horrible for turbo life.

718 may have one or more pumps keep moving oil after the ignition is turned off. There is certainly plenty of activity going on under there after I turn my 718CGTS off. Fans for sure, but maybe more?

:)

yes the 718 not only runs the fans but keeps the oil circulating as well. no need to drive around for 5 min. or more.
 
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