nariman

i was told do do oil change once a year
is that ok even if i take the car for autocross?

do you ever add oil?
or just wait till next oil change?

Thanks

carsnob

Actually now that you mention it, I found it unusual when first driving 911's that one had to add oil (996's & 997's).
However in my 2017 -- 991.2 I've had it for a year and never once did it require a top up. (Just scheduling an oil change now.)
Has anyone else added oil in their 991.2 as frequently as with older models?

Hurricane

No, you will be fine with your annual oil change unless you are putting crazy high miles on it (more than 10k miles a year). If it is low on oil, you can add oil (the two 991S's that I've had never consumed oil in between oil changes, at least none that moved the electronic readout, anyways). You will be fine for autocross, too.

ThePhanatic

As long as you are replacing the oil every 12 months / 10,000 miles you are fine to do autocross. If it needs a bit of oil to top up, you can do that, but I've not experienced that.

Macster

Years ago when I autocrossed -- my Datsun 510 set up with front/rear sway bars, dual side draft Weber carburetors, Isky cam and some other bits -- my auto tech buddies -- who also autocrossed -- told me to always show up with fresh oil in the engne.

My advice is you do the same for your 997. Show up at every event with fresh oil.

For my two Porsches (Boxster and Turbo) and for any of the cars I have had over the years, I add oil when the level gets low enough that at least a half a quart of oil is required to bring the level back to the full mark.

Be aware if you can check the oil in your car cold the level will read lower than if can check the level hot. (I can check the level cold or hot in my Boxster and have observed this a number of times. I can only check the level hot in my Turbo.)

So if you check the level cold and find it low do not add oil unless you limit the amount of oil to a quantity that you know will *not* have the level too full when the engine and its oil are up to temperature.

You should get into the habit of checking the oil periodically. With my Boxster I check the oll level -- cold -- before the 1st engine start of the day, which M-F is when I begin my 30 mile work commute.

At the office I check the oil level when I head out for lunch or at least before I head home from the office.

In both cases above the oil is "cold". I like to when I can take the opportunity to check the oll level once the engine and engine oil are up to temperature.

If I stop someplace on the way to or from the office -- and the engine and oil are up to temperature, I'll check the level.

At other times when say I'm on a road trip, I'll check the oil level when I stop for fuel, and then in the morning before leaving the hotel.

With my Turbo since I can't check the oil level before heading out most of the time for work I check the oil level when I park the car at the office. Since the manual calls for a 2 minute idle to allow the turbos to cool I have time to check the oil level and if I find it low enough -- as was the case yesterday -- to add oil to bring the level back to the max line.

Then when I arrive at home after work I check the oil level while I let the engine idle before shutting it off for the night.

And on a road trip I check the oil level when I stop for fuel or when I stop for a food break or a fuel stop.

Since it is so easy to check the oil level in the Turbo as long as the car is level and and stationary (and the oil up to temperature) I can even check the oil level at a stop light and do. Not every light but just once in a while.

My point is you want to get into the habit of checking the oil level so you can know ASAP when it is time to add oil. Oil is a vital fluid critical to the engine's health and while the engine won't expire if the level is even a quart low I see no reason to make it a habit of letting the oll level get a quart low without bringing it back up to full again.

nariman

i drove only 4 k miles so far
thank you all

R_Rated

I would do fresh oil after every event.... maybe replace the filter every other time for autocross but for road racing - a full change. 1 Year 10K miles is for road use - track use is a whole other animal. Even the filter though... under 20 bucks. Amazon and Walmart sell Mobil 1 cheap.

Ynot

I've owned the 997 for over 7 years now, not once had I had to top off oil. If you drive less than 10K miles a year, just do it once a year, that is what I do.

StormRune

The local autocross club here runs events almost monthly, although I only attend about 3 or so a year. That would be a lot of oil down the drain in my opinion, but I do change oil about every 4-5k miles just for good measure since I always hit that before a year is out. My last Blackstone report was taken after two autocrosses and a lot of driving and showed stellar results so I'm comfortable I'm okay there.

I just don't see how 5 or 6 hard 30-60 second runs requires an oil change. That's all we ever do in our autocrosses here anyway; maybe some clubs do a lot more runs? Maybe this was needed with 20-30 year-ago oil and engine tolerances that allowed more blow-by and such, but today's top synthetics and engines are far better than back then.

There are two big things that I do think is important for protecting your engine at an autocross that I see very few do.
1) Start the car well before your group's runs start and make sure to keep the oil at least 150 or better before rolling out into the starting grid. Then if you end up waiting there a while (usefully when in the first group), restart the car as needed to make sure the oil doesn't get too cool.
2) After each run I don't turn the car off for quite a bit until both of the temperature gauges stabilize back to normal for idle. It is even in the owners manual that you shouldn't turn the engine off immediately after a hard run, but so many do. You need to keep the oil and coolant circulating to pull the heat out of the local hot spots within the engine. This allows it to cool down more evenly to prevent warping-related problems from significantly uneven internal temperatures.

Homeles

Oil's cheap. Engines aren't.

nariman

just in case if i need to add, is it a must to add same Mobil 1?
because i have pennzoil at home , i think i have 5W 40

nariman

i opened the oil cover and i don't see the dip stick there

StormRune

FYI, I just got back the Blackstone report for a earlier-than-usual oil change. I decided to sync up the oil with other 30k services I was taking care of. Note that this oil was in the car for three autocross outings. I think it helps validate that you don't really need to change oil after every autocross since this one has three autocrosses under its belt with no signs of ill effects, with the last of those just a few days before this change.

I was using 5W50 Mobil One based on a thread LexVan had started a while back: https://rennlist.com/forums/991/8103...-on-991-a.html. See the Blackstone report for this oil below, it seems to have done very well. The "thin viscosity" they noted before was with the normal Mobil One 0W40, not the European Formula I'm trying now. Their comment about 3800 miles is wrong BTW, it was only 2800 miles this time.


However, this time I'm going to run Mobil One 0W40 "European Formula". I recently saw a report that talked about how it was significantly outperforming the normal 0w40 and holding up as well over time as the 5W50 (but I can't find it again! I'll look more later) also had the opportunity to talk with a Mobile One engineer out at COTA during the recent Cup races. He thought either the 5W50 or the European Formula 0W40 would work great for me, so I thought I'd compare the differences. Note that I also had to decide which to use before I got the Blackstone report back. I might have just stuck with the 5W50 if I had seen it first. Note that I am in Central Texas so cold temperature performance isn't a big deal here but high temperature performance is.

GTSMeister

What is this non-european M1 0w-40 oil you speak of? Is it old stuff? Since at least 2004, M1 0w-40 has always been labeled "European" since it carries VW, Merc and Porsche approvals.

Here's the current pdf list of oils from the Mobil site. There is only one 0w-40 oil listed.

917k

Mine coming up for a year and no, not had to add any oil