987FL, Semi slicks and oil lubrication

Hi there! I read a lot about semi slick tires (e.g. Michelin Sport Cup) and the lubrication on the 987, and there are different opinions out there. Next year, I want to switch to semi slicks like the Sport Cup or the new Dunlop Sport Maxx Race. What I'm still concerned is the oil lubrication and the lateral g-forces on my occasional track days. I drive a CR and read a lot about the 987 non-FL definitely having issues with semi slicks and it's lubrication. The 987 FL with its DFI-engines, seams not that endangered. At least that's what people say. Even my Porsche garage (which organizes several track days a year) recommends me switching to semi slicks. A month ago, I also met another CR on a track with semis equipped and he sayed he's not having issues. But not having issues and putting your engine on the risk of piston jamming are two different things in my eyes. I won't track often, let's say 2-3 events a year. But driving at Dijon for example, with the long bend high-g curve (180 degree 130kph-150kph) lets me hesitate a bit if the 987-FL lubrication can cope with that force. (Whatever the Porsche called "integrated dry-sump" is) Do you guys know more facts, of the 987-FL engine does or does not suffer from lubrication issues with semi slicks? Of course, a real dry-sump is always the safe way, but as long as I'm on warranty I can't modify my car.

IIRC (at least this is the case with the older cars) Porsche voided the warranty on cars used on the track with track tires. The levels of grip and resulting g-forces could result in engine oiling problems. So if you take the car on the track that already voids the warranty. But read your owners manual warranty section carefully for this might have changed. But if I'm right then you must for the sake of your car's engine and your peace of mind (and bank balance) you must take steps to ensure the engine can not suffer any oiling problems on the track. Thus were I in your shoes I would not need any more info than that, admittedly gained by reading between the lines, and take preventative measures to prevent any oiling issues. AFAIK this would be to fit an AccSump (or similar) system designed to provide sufficent oil pressure in the event of a temp drop in oil pressure due to oil starvation from high g-forces, a deeper sump and one fitted with baffles designed to counter the g-force effects to avoid triggering the AccuSump in the first place, and possibly even fitting or considering fitting (if they exist) extra oil scavaging pumps to deal with oil accumulating under the camshaft covers under hard turns/during hard braking or in other high g-force scenarios. It is in this scavage pump area the integrated dry sump systems at least in the earlier models of cars came up short. One pump per camshaft cover is fitted and under certain high g-force conditions oil can collect away from the pump to the point the oil level in the oil pickup area drops dangerously low. One doesn't wait for signs of an oiling problem -- unless you have a source of very cheap replacement engines -- he anticipates them and takes steps to ensure they never appear. Sincerely, Rockster.

Here is some info from LN Engineering

but not gen 2 DFI engine related info though ...

This website has threads about the comparison of the Gen 1 cars oil pressure on track versus the Gen 2 cars. The results showed that the Gen 1 cars do not maintain oil pressure under hard G corners. Thus the need for Oil mods when moving to sticky tires and faster lap times. The Gen 2 cars showed much higher oil pressure and the oil pressure maintained sufficient levels >40 psi during hard cornering. So, no need to modify a Gen 2 car.

This is true, but the oil pressure on Gen 2 was on street tires. I'm waiting for Joe to test out R compounds (Nitto NT-01's) and do the oil pressure data log again.. BTW, I wouldn't call MPSC's semi-slicks. They are R compounds (can legally drive on the street) and considered by many to be not that good either ("semi-R comps").

Good Point to perform empirical testing on R compound tires since they do allow for higher G forces.

About the tires: The semi slick tires I'm talking about are street tires. If street tires are the restriction to the warranty there would not be a problem with tires like the Michelin Sport Cup. Real race tires are a different story. The question is, if Porsche can couple the warranty on the limited tire choice, saying street legal but only specific tires. I'm interested if they can. The oil-pump solution is safest, I get that. But modifying my car would also result in loosing the warranty on the (expensive) motor-part. So this is a dead end at the moment. Additionally I'm not a big fan of modifying a car to track usage with just 3 track days a year. This will cost me thousands of $ on the resale, people here don't want cars that have been driven often on the race track. Currently, I don't know where I can find the detailed warranty descriptions. I think I'll contact my dealer to clearify this point or contact Porsche directly. I want to see the part in the warranty description where it says that specific (but street legal) tires will result in the loss of the warranty. It feels like that gen2 987 engines have a better oil supply. But that's still just an impression.

My advice after 15 years of HPDEs. Chase the fun, not the lap time! Sure, you can strap on higher performance tires and get a modest improvement in lap time. Trust me, the thrill of that quicker lap time will fade quickly and then you are back looking for the next killer mod. I'd stick with the tires that Porsche designed the car for and just have fun. And not worry about oil starvation.