speedread

Any knowledge or educated guess if a 997 engine would last longer than a 996 engine on the track.

38D

Can't imagine it would. It is basically the same design as the 996 (which is vastly different than the GT2/3 or Turbo).

mooty

not really. they are basicaly the same motor.
but 996 motors though not as well built as air cool'd. it's really not that bad. lots of them are ran very hard here in CA, not racing, but heavy DE, very few blow up.

i have had 7 996's only 1 had RMS. if you are racing, GT3 or older 911 is the way to go, if you are DE'g, i wont be too afraid to abuse the crap out of 996 997.

10 GT3

Long blocks between the 2 are exactly the same: same block, crank, rods, pistons, heads, cams, intake and exhaust manifolds. The use the same oiling system with only minor changes in the 997 for the cooling system. The only differences are in the intake (airbox), some accessory routing, the exhaust, some engine wiring and the ECU. Bottom line, is expect no difference in long term durability. If you are going to do more extended track running, you can increase durabilty with a 3rd radiator (standard on GT3's and X51's) and a racing oil cooler.

karlooz

^
and 996 engines are cheap so go ahead and abuse them, rebuilding an aircooled is twice as that of replacing a 996 engine. stock for stock, the water pumpers have higher output per specific displacement.

there's someone down south who is trying to convert the 996 engine to carbs so that they can be fitted to older 911s. sacrilege but you can't deny the HP/cost.

back onto the subject.... the 997 motor should be the same as the 996. same manufacturing process, same wet sump. if the 997 has the oil scavenging kit then it's a plus.

JimB

I've got to disagree with you Moot. 996s make great race cars. Mine has been fast and very reliable. Most others I know of have been to. All race cars have problems. I don't think you would find air cooled p cars to be any more reliable than 996s.
Jim

38D

Have to disagree. The air cooled cars are far tougher in many ways. Wheel bearings, dry sump, etc. There was a guy that blew up a boxster motor at Lime Rock this year. Put a rod right thru the top of the case. Everyone figured he overrev'd it, which wasn't the case as it was a tip!

99firehawk

the newest 997s should have the updated intermedate shaft thats a major imporvment over 996s

JimB

I've tracked my 996 for seven years and club raced it for four. I've replaced one wheel bearing and have had no serious engine or transmission issues. I've only seen one 996 engine blow in club racing. That was Chris Cs right in front of me at RA four years ago. I also watch Grand Am Cup whenever possible and I don't remember a single engine failure. Would I rather have a dry sump, water cooled engine as in the GT3? Sure I would but I would never discourage anyone from racing a 996. Frankly I love the idea that I can run the car for three or four years and then drop in a new factory rebuilt engine for $10k.
Jim

38D

There will always be people that have good experiences. However, I personally have seen more serious issues with 986/996 based cars than on the air cooled cars. That's just my experience. Does it mean that every 996 will fail? Absolutely not.

Btw, the Grand Am cars can run accusumps and I believe that most do.

mooty

jimB, i know you run your car to death and i sure hope my gayman will last as long as your c2. i really love the chassis. and when the 3.4 goes, i will stuff a 3.8L in there. i spoke to many tuners, it's impossible to get gt3 motor in there, cooling and wiring issues. well maybe if i coughed up 100k on top of donar car, someone can figure it out. but even i am not so insane.

38D, i am not that well versed in racing. could you please chk and confirm that gram am cars run accusump? if so, i am getting one in my car immediately. TIA.

38D

GrandAm rulebook section 7-8.8: Engine oil Accu-sump system and valve is permitted.

You can see the accusumps in several of the cars on TV, but I am not 100% sure about the 996s/997s. Terry Heath runs in Grand Am in a 997. He will be at the Daytona club race, so I will try to rememer to take a look up close.

JimB

Moot,
Give Adam or Gordon at Autometrics a call. Adam might actually see this thread and respond. They've built a few GAC cars and will know the answer. I still think 996s with a problem are the fluke, not the other way around. Like I said, I haven't seen one fail at a race in the last three years. (knocking on wood)

Also, the 996 chassis makes a great race car and most of the cup car and R/RS/RSR suspension parts bolt right on. Just my 2 cents worth.
Jim

Glen

The 996 has the same wheel bearings as the Cup and GT3 btw....best C car for the buck these days far and away. 993 TT has the biggest advantage but less so vs a well equipped 996 these days. The 6 chassis is far superior to the 3 and 964 at high speed in addition to huge aero advantage. Lots of very well driven 964 and 993 RSCS cars out there, hence the preexisting assesment they are superior. A well driven 6 and now a well driven 7 will be much cheaper to run and more succesful. The driver still is the seperator so I guess the class is pretty well set these days.

Bull

That was one big hole in that case!