smokey

Tony Kelly, when you did your refresh on the 951, how was your no. 2 rod bearing? I just got a 944 Turbo S with a refreshed engine (rings, bearings) and I'm wondering whether to put the trap door in the sump that I had on my previous 951. With an extra oil cooler and Amsoil, I hope I'll be ok, but am always looking for more data. Sorry if this is off topic.

mitch236

I was going to second the Boxter sentiment. My friend had a Boxter and he just showed up and drove. Wheel change later and he was out on the town. The maintainence was limited to brakes and tires and fluids. The upfront cost is high but resale tends to be high as well. One drawback is that one biff ruins the equation

GrantG

Just don't get carried away with slicks and coilovers on the Boxster, since the wet sump is not designed for those kinds of lateral loads...

TMH

I have to agree with most, but not all. We bought an '87 Coupe last year to dedicate to the track. Much of the hard stuff had already been done by a PO who wanted to "prepare it for autocross": Recaros, 5-points, roll bar, front brake coolers, mild chip, cone air filter, revised rear adjustable spring plates and poly bushings, camber brace, Bilsteins, etc. We ended up buying the car for less than $11k (not a deal that comes along every day)!

I have done almost nothing to it other than removing the features which still made it somewhat "streetable" (but heavy). Also, before I started running it last season, I did an oil change and replaced the brake pads.

Well, that old engine has about 165k miles on it, and with all of the stuff I have removed, I have the car down to between 2500-2600 lbs. I also put on a cat bypass pipe and gutted the stock muffler.

After 12 DE days, that car has never skipped a beat, and although I do not threashold brake, I haven't even needed to replace the brake pads! In all the time I have been running DE's with that car last year, I: Replaced the spark plug wires (not due to a "need", but as preventative maintenance), one additional oil change, and one brake system flush and bleed, and replacing the tranny oil with Red Line after a couple of DE days (was getting kind of notchy going into 3rd - The Red Line cleaned that up completely). That's it.

Granted I don't punish a car like a real racer, but I am very happy with running 12 uneventful DE days at such a low cost.

Tom

APKhaos

The engine is still out. With luck, it will be buttoned up this weekend. The rod bearings worried me because of the street talk about #2 failures. The fact is that the bearings on all four rods were gorgeous. I could have put them back - they were perfect. I replaced them, but kept the old set to take some pics for the record. This is an engine that is raced hard [no street driving], regularly runs into the high 6K rev band, and had the occasional excursion over 7000. I have the fully sealed baffle setup in the oil pan, an external Mocal installed halfway through last season [PO ran with stock oil cooling only], Mobil 1 15W50.

38D

Don't the boxster/996 have an "integrated dry sump", where the the oil tank is part of the block? Maybe not as robust as the old air-cooled style, but still better than a wet sump...no?

38D

I found this description of the Boxster's sump from 986faq.com

"PAG claims that the Boxster engine has an "integrated" dry sump, yet there is only one drain plug and no oil reservoir as on 911's. The instrument panel gauge and the dipstick read from the same source. There is an oil pump in each of the camshaft housings for oil return. The biggest difference from the 993 dry sump is the sump is located within the engine block on the Boxster rather than beneath it as in the 993. The sump, by definition, is the bottom of the crankcase where the oil flows to and collects after being pumped over whatever surfaces it was intended to lubricate/cool. The 993, and every 911 before it, uses a scavenge pump to pull out the oil as it flows into the sump and pump it into a holding tank under the right rear fender on all but a couple of early model years. Hence the term "dry sump;" oil is not allowed to sit in the bottom of the crankcase and so the sump remains (conceptually) dry. The main oil pump takes oil from the bottom of this holding tank and pumps it back into the engine's system of oil passages. The advantage of this system is that it prevents oil starvation during hard cornering. With a conventional wet sump system, high cornering loads can cause the pool of oil sitting in the sump to slosh away from the oil pump feed tube. With the dry sump's large vertical storage tank, you'd have to turn the car upside down to keep oil away from the pickup point. In the Boxster and 996, the tank is integrated into the engine block below the crankcase.

There are two techniques for oil to get from the crankcase to the tank below it:

A hole in the wall between the crankcase and the tank lets gravity flow the oil from the sump to the tank. If that's the case, then this is really just a conventional wet sump arrangement with an extremely large and well designed sump. Baffles and walls are designed into the sump to prevent the oil from sloshing out during cornering and the high capacity should ensure that plenty of oil is always available at the pick up point. A solid wall between the sump and the tank prevents oil from flowing between the two. A scavenge pump moves oil from the sump to the tank when the engine is operating.

Both techniques are used in the Boxster. There are two oil pumps that take oil from the cylinder heads to the main oil pump. This oil is fed into swirl pots to be centrifuged and defoamed. There are oil collection channels cast into the crankcase to return oil to the oil pump."

smokey

Thanks for the insight, Tony. The "fully sealed baffle setup in the oil pan" - is that the updated OEM baffle or a trick setup?

APKhaos

Stock turbo S baffle, fully sealed all round with RTP. Only tweak is a simple Al sheet piece between the stock baffle and pan. Email me & I'll send you a pic.

Doug Donsbach

Hey Tony, what is "RTP" and how do you get that engine to spin past the rev limiter?

Steve Rea

Well, we're going to see just how reliable this one will be:

http://www.renegadehybrids.com/LS-1/...ersionkit.html

We're shooting for the great handling performance of the 944, with excellent reliable chevy power...the cool thing is that I've heard the ls-1 is basically the same weight as the 944 turbo engine +/- 15lbs or so.

Steve

APKhaos

RTP is RTV - sorry. Permatex Red or Grey.
What rev limiter? Its PCA-legal to chip the DME. Mine has the rev limit parameter set to a very high value. Its effectively a driver controlled rev limiter.

Chaos

Spec Miata ?
Really my S2 has cost afortune to race. One Transmission is all it takes !
Plus the build cost,look at Grassroots and Excellence and compare prices. Porshe people get robbed !

Larry Herman

So your car is an 89, which was only available in the S spec. How do you run PCA E stock with a chip?

Mark in Denver

Got 'im!