Planet-9 Porsche Forum banner

1 - 20 of 35 Posts

·
Administrator
Joined
·
34,503 Posts
Discussion Starter #1
Someone start that whistle music please and give me your best Clint Eastwood stare!


I'm back from my first day at the BMW track event at Heartland Park and have some items to report. First, for those who doubted the horsepower gains on my car I offer the following.


Before Modifications

Top Speed at Alpha Zero 110-115 avg. 118 tops

Top Speed back straight 92-96 avg 100 tops

Lap times 2:02-2:05 avg, 2:00 tops



After Modifications

Top Speed Alpha Zero 118-122 Avg. 126 tops

Top Speed back straight 102-105 Avg. 108 tops

Lap times 1:59-2:01 Avg - 1:55 tops


So yes, I'm pleased with the results! New harness bar and harness worked great!


Now for the not-so-good news.


1) I belched oil smoke not once but twice, (2 different runs), both times after coming out of the esses in the back part of the track. I surmised that I was sloshing oil around and somehow got it into the intake then belched it through the motor. Stan at Mantis is checking into this for me, perhaps I was a little overfilled on oil.


2) During my last run the check brake pad light came on, but after I pulled into the paddock to check them it went out. Stopped by dealer and they said I had 50% pads left, so maybe it got hot and gave a false reading. Anyway, the problem went away, not sure if Mooty, Sleeplessor anyone else who tracks regulary has had that happen?


3) My 1st set of Michelin Pilot Sport Cups are to the cords!!!! - Ugly!!!





Great times, I'll post some pics vids as I can!
 

·
Premium Member
Joined
·
324 Posts
with all of the great modifications to your car how could anyone doubt that your car would not be faster!! Time to call tire rack and order a new set of tires to get you thru until spring 07 hopefully.
 

·
Administrator
Joined
·
34,503 Posts
Discussion Starter #5
No suspension mods, I have PASM (was running in sport mode), so I'm waiting for a PASM full coil over or something like that for the track.


BTW there was a 997 C2S there driven by a guy in group 4 who is a good driver and he was unable to put any distance on my car, after I paced him down the front straight he asked me back in the paddock what I had done to my car as I'm sure he didn't expect to see me glued to him like that in the straights. I told him what I'd done and he's been to the same shop as I have (Imagine Auto) but didn't share if he'd done anything to his car or not. I don't think he did, but I don't know for certain. We were both much faster than any BMW's we came across. :)
 

·
Premium Member
Joined
·
921 Posts
1. Oil belching - Spoke to Mantis and it turns out the sump extension does not do anything for the oil getting sucked into the intake, it only adds more oil to the system as extra insurance against oil starvation. Mantis is in the process of producing a fix for the oil in the intake issue.



2. Brake wear light - I always remove the sensors from my pads and zip tie them out of the way so have never had any issues with them. My guess is that either the heat affected them and created a closed circuit, or the connector in the wheel well is loose (the sensors and a lead wire are replaceable so there is a connector for the lead wire that you can check).



3. Mooty and I are getting about 4 track days per set of tires. We are both using Toyo RA1s or Nitto NT01s. How many track days did you get before cording them? Was it the outside front tire? If you are experiencing any sort of understeer, don't let it slide, it will kill the outside edge of the tire... just slow down a bit to save the tire.



Excellent results from your mods.



Regarding the C2S: Yeah, given your power output, I wouldn't expect a C2S to begin pulling on you until well past 100MPH. It takes rather hefty power differential to make a very noticable difference; people don't realise this when buying cars and think how they are going to blow away those cars that have 50 less HP... it isn't enough...

Edited by - sleepless on 08/18/2006 7:10:16 PM
 

·
Registered
Joined
·
384 Posts
I had the same thing happen with my brake pad sensors. I think my pads got so hot that a chunk broke away on one wheel right where the whole in the pad for the sensor is. The light would then come on when the brakes were hot, or if I washed the car and then go off again. Just ignore the sensors and visually inspect the pads. Although since I have had the race pads in I am getting at least twice the wear... But now I have cracks in my discs! probably inevitable given the heat I am putting into my brakes. I often do 6 or 7 laps in a row and always stomp on my brakes before tight corners until I get a slight pulse from the abs and then ease off.
 

·
Registered
Joined
·
764 Posts
5 seconds on the 2.5 mile GT layout would represent about 550 feet more track covered per lap versus the stock time. That is a significant number that probably cannot be accounted for just by driving a bit more aggressive, having a better line, etc...


Paul
 

·
Administrator
Joined
·
34,503 Posts
Discussion Starter #12
I don't think anyone has accused me of not driving aggressively.... although the C2S owner said on our first run he was taking it easy, the next time out I don't think that was true and I was still on him like glue.


Pete, good to hear that Stan and Mantis are working on the oil sucking into the intake issue. I'm assuming that running a little lower on oil might be a temp fix since it didn't happen to me at my prior 2 events. I am curious why this happens in the Cayman motor but not the 911 (as far as I know). The only thing I can figure is that with the engine centrally located it is more prone to sloshing the oil somehow?


I got 5-1/2 track days out of these Michelin Pilot Sport Cups and at least 1/2 of those were in 90+ degree ambient temps with a hot track so I'm not displeased. Although the outer shoulder was the first to show the cords, by the time I finished my last run of the day I had spots where cords were starting to show from the outer edge to about 1/2 way in on the tire.


I did tinker with tire pressures and was happy with 34 front and 36 or 37 rear COLD pressures, seemed to create a very even wear pattern.


My 2nd set of MPSC's are on the car now so I'm good to go for more track days. I'm hoping to get through the end of the year with them as I've only got a couple more events in this area before winter sets in. If I travel for a track event I may need to investigate some Toyos or Nittos.


I concur that an article about removing the wear sensors and tying them back out of place would make for a nice addition to our library here, should be a fairly simple photo shoot next time you have your wheels off.


I have no rotor cracks, but I'm still on my stock pads (bet you guys are wondering how I make these babies last aren't you?) /fckeditor/editor/images/smiley/MWPX/tounge_smile.gif I'll probably go with a set of Hawks soon though as my added HP and at some point modded suspension is going to require some firmer and longer lasting stopping power. I'm starting to second guess whether or not I should have just bitten the bullet and gotten PCCB's in the first place...


Tomorrow I get to see what an Exige can do! Oh also there was a new Z06 at the track on slicks and we never found each other throughout the day, I never caught him he never caught me so I can't say how our cars compare, although I'm assuming his is faster evidently not enough to catch me on a 2.5mile course during the time we were out there.


Last but not least there are still 2 spots on the track where I'm not comfortable heel-toeing and that's what I worked on most of today as I feel like I may be able to shave a little more time. I could also shave some time on the last turn on the track before entering the main straight if I had a limited slip differential as it is a tight turn and too much throttle always causes wheel spin there so I'm constantly feathering and looking for the best line but my speed can really vary by as much as 10-12mph coming out of that corner depending on how well I execute it. But hey that's what seat time is for, practice practice practice!
 

·
Registered
Joined
·
1,094 Posts
1) I belched oil smoke not once but twice, (2 different runs), both times after coming out of the esses in the back part of the track. I surmised that I was sloshing oil around and somehow got it into the intake then belched it through the motor. Stan at Mantis is checking into this for me, perhaps I was a little overfilled on oil.


2) During my last run the check brake pad light came on, but after I pulled into the paddock to check them it went out. Stopped by dealer and they said I had 50% pads left, so maybe it got hot and gave a false reading. Anyway, the problem went away, not sure if Mooty, Sleeplessor anyone else who tracks regulary has had that happen?


3) My 1st set of Michelin Pilot Sport Cups are to the cords!!!! - Ugly!!!





Great times, I'll post some pics vids as I can!




i tend to overvill my oil, though never had oil spilling out. do have blow by white smoke syndrome.


with regard to brk pad sensor, i think your light came out due to heat, assuming the sensors are not yet fried. if you cont. to track a lot, i would just cut the sensor off and tie them together. you can see the brake pads just by looking, so i dont care for the warning light. also with the sensor in place, it's harder to change pads and some pads doesn't have holes there for the sensors.
 

·
Premium Member
Joined
·
340 Posts
K-Man S,


Were your MPSCs shaved or heat cycled?
 

·
Registered
Joined
·
831 Posts
Generally, for 'heat cycling' to actually do good for the tire, you need first heat them running on them, then let it cool off for about 2 to 4 hours to ambient temps. For life of the tire, it won't make a difference however, but may do so about ultimate grip. I rarely notice the difference though,but more experienced drivers tell me they do.
 

·
Registered
Joined
·
489 Posts
kmanS, the temps that you mentioned for the pcups cold seem way too high. you should be 34 to 35 hot. I have6.5 days on my pcups right now and I probably have 2 more days left. A few of those days were in 95 degree plus heat at VIR.
 

·
Premium Member
Joined
·
728 Posts
K-man S

QUESTION:

Is your clutch stock and still any good?
Are you still with factory brakes?

If so then your car is an incredible specimen of a Cayman S. It gives us all hope.

ZEDD06
 

·
Registered
Joined
·
1,558 Posts
Ken: I agree with Craig on the tire pressures in the Cups. Michelin says to shoot for hot pressures in the 32-36 psi range. On warm days that usually means starting pressures somewhere in the mid-20's.
 

·
Administrator
Joined
·
34,503 Posts
Discussion Starter #20
Well from my track experience with the pressures in the MPSC's if I go that low I roll them over and the shoulders wear terribly. I talked to the Michelin reps at Porsche Parade 2 weeks ago and they suggested starting at 30-32 cold and go up from there as needed. I found 34 to be about right for the fronts and 36 for the rears although those may not have been completely cold temps, but they weren't hot off the track temps either. I'll monitor it more closely next time, but certainly I squeeled far less than I did in those prior viper chase videos and I was turning faster laps.
 
1 - 20 of 35 Posts
Top