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Some recent suggestions:

Type 1 Driver- Car is a daily driver doing 10-20k miles/yr. Cost, longevity, and road manners are more important than ultimate grip. Nexen 3000, Sumitomo HTRZ III, or a performance all season tire would be a good choice here. They don't cost much, have good grip, ride nice and last a very long time.

Type II Driver- Car is a weekend joyride with occasional Auto-X, track days. 5-10k miles/yr. Max grip and road manners are more important than cost or longevity. Mich. PS2, Bridge. RE050A Pole Position are good choices.

Type III Driver- Car is a weekend warrior. You live for track days, Auto-X and canyon carving. 3-6k miles/year. You take your track days seriously but don't want to drive around town on R-comp tires. Max grip is everything. Ignore the cost or longevity. You don't care if the ride is more harsh or a little louder. You are in a PCA points race in Stock class and you want to win. Dunlop Direzza Z1 Star spec, Yoko AD07, or Bridge RE01R, are your best choices here.

Eric,

It looks like you are getting closer. Narrowed down to a failed DME, failed sensor harness on bank 2 or a mechanical problem in bank 2. When you get a CEL, what codes are you getting? If you get codes on bank 2 only that would eliminate the "DME rich mixture theory" as the mixture would affect both banks equally.

Depending on the codes you get I would look hard at the connectors and contact points between the bank 2 sensors and the DME. You may have a connector making poor contact but functioning until it gets hot. The connector expands a little and then sensor voltage fluctuates.

I understand your frustration. I considered variocam timing also but if that were the issue you should get error codes as well. No clear indication of failure yet. The problem may need to get worse before the source becomes clear. Swapping sensors is a bit of a shot in the dark at this point but you might get lucky.

Eric,

Very strange indeed. We can eliminate drivetrain issues and focus on the motor. If the DME is working properly it would be throwing error codes for fuel mixture, timing or throttle body issues. Low fuel pressure would be more noticeable at high rpms than low. Internal mechanical binding when hot is still possible, faulty DME, what else are we missing?

Don't know about the Q on neutral versus in gear.

Just a process of elimination. If it runs lousy or stalls when hot and in neutral this would eliminate other drivetrain issues and isolate the problem to the motor. If it only runs lousy and tends to stall at low rpms when hot and in gear I would look at the drivetrain. Does the car coast in neutral freely when hot? Sometimes a bearing will bind up when hot without making much noise.

Bump and an update.

On the bump -

I'm still hoping someone can tell me by looking at the pre-cat O2 sensor data, if I have a bad sensor or two.

But in the meantime, I have pulled all the plugs - they looked fine - I replaced them since I had done all the work anyway. The coil packs also look fine; no corrosion, connectors were tight.

I also pulled the MAF. It was perfectly clean.

Idle is fine, so, while I haven't looked for vacuum leaks, it seems unlikely.

Anyone hazard an interpretation of the O2 sensor data or have a theory???

Just some thoughts:

The DME is pretty sensitive to mixture and timing. If it were a mixture or sensor problem you would surely get a CEL and error codes. Is it burning oil? Any oil in the coolant? Does it only happen in gear or in neutral also? It sounds more like something is binding when fully heated up. I used to do some motorcycle racing and my track bike would sometimes act like this when it was due for a rebuild. Rings, bearings, CV joints come to mind. Hopefully something simple. Good luck and let us know what you find.

Music sound systems are very personal choices. We all have different ears and different perspectives. What sounds good to one person may sound awful to another. I will share my biases and suggestions for what it is worth. I hope you find it helpful.

I am a classically trained musician. I listen to a wide variety of music on a wide variety of sound systems. Some very expensive...some not so much. I don't pretend to have "Golden Ears" but I do know what I like. My goal with any sound system is smooth, natural, reference quality sound from around 50hz-16khz, good imaging, reasonable volume, and low distortion, at a fair price point. I have no use for the "Boom and Sizzle" car audio that is all the rage with kids these days.

Suggestions:

The Becker sound system is marginal at best. The radio is lousy and it's components don't play well with others due to the MOST fiber optic system and non-standard crossovers and output impedance. Adding really nice speakers to the Becker system is a little like outfitting a monkey in a prom dress. It will surely sound better but you will never fully realize the potential of those fine new speakers. If you want a sound system that really works together well, start from scratch. You should be able to do a system using all quality components, that sounds great in the car (not down the block) for $1000-$1500 USD. Choose compatible components, keep it simple, install them with care, and enjoy.

Nice head units- Alpine, Blaupunkt http://www.crutchfield.com/p_500CDA9887/Al...l=N&tp=5684

Nice Speakers- MB Quart, Boston Acoustics separates (I favor the Bostons because I have been using them for 20 years but Quarts sound excellent as well) http://www.crutchfield.com/p_065PRO60SE/Bo...tures_and_specs

These components will sound great if installed and set up properly with a calculated maximum volume of 107db (moderate loudness). If you want deep bass below 50hz or want it louder, you will need to add a sub and an amp. Happy shopping!

A relevant tire thread.

http://www.renntech.org/forums/index.php?showtopic=20098

"They tell me that the wheels are not bent. I assume that they can detect a bent wheel by balancing the tires."

They should see them while balancing. I have two bent wheels in my garage. They will balance fine but still clearly bent. Worn front end bushings, worn wheel bearings. Anything I missed??

Thanks for the update Grover. My current PS2s should be toast in about two months. I will seriously consider those Dunlops.

Check it out.

http://www.renntech.org/forums/index.php?showtopic=20098

Great. So some yoyo thought that the car would run better if he just clipped a sensor wire here or there??? Classy. Or maybe the last owner refused to pay a repair bill so the mechanic left a little surprise behind. :angry:

Porsche OEM wheels are "forged" so they are strong and most are reasonably light weight for best performance. Aftermarket wheels from China range from very good to very very terrible. A "cast" wheel will bend or break much more easily and they are often a little heavy which affects performance. The low price leaders in aftermarket wheels are always "cast" wheels so you get what you pay for (low quality, low price). People here in the USA change wheels as often as they change shoes so many wheel shops have "take offs" for sale cheap. You may be able to find your exact replacement OEM wheel online through one of them and have it shipped today for a fraction of the cost of new. Good luck.

Drive both cars and pick one! Great reasons to go either way. If I were shopping for new today I might hold out for a PDK tranny. Not quite ready to trade in my good ol' 986 though.

+1 on Circle Porsche. A very customer oriented dealer if there ever is such a thing. Ask for Matt and tell him a PCA-GPX member sent you. He will treat you right.

Gus,

Your DPDT switch wiring diagram is correct assuming your source for 12vdc is the switched/fused OEM horn circuit and not direct from the battery.

Yes. As long as both horns have neg. leads to ground a Single Pole Double Throw switch will be fine. Connectors are your choice. Hot lead to switch, one lead to each horn. Done deal.

Why not just install a DPDT switch to control your horns. Switch down for DOT approved OEM horn, switch up for Mariachi party. :D

Radio shack is your friend.

P0134 Oxygen Sensor Ahead of TWC, Bank 1 – Interruption of Signal

Potential causes:

– Wiring harness

– Oxygen sensor

– DME control module

Did you check the wiring harness?

Was the right sensor changed?

Yes, right sensor was changed...lost code P1126 (if I remember code right?!)...P0134 only code i get...well, will either be wiring harness (nothing dodgy apparent) or DME then..sigh...any money its the DME!

Never straight forward this...any checks I can do that do not require much messing about?

Mouse chewed the wire harness?? It happens.

Sorry man. The worst possible news... your baby is dead. As a second owner of a 10 year old car, any sort of legal remedy is probably approaching zero. I think the MFG warranty was 2 yrs/24k in 99.

two choices:

Fix it- repair or replace motor $$$$ I would weigh the good "takeoff" motor vs a Raby rebuild.

Sell it at a loss- Not running ($$$$)

Either way it is going to sting. I do not envy your situation. It could happen to any of us tomorrow though.

The only "inside" windshield repairs I know of involve Scotsch tape and bubble gum. If it has not run and is not directly in your field of vision just leave it alone. Once it runs, put in some fresh glass.

Yup. That plug is toast. Unusual to strip away the ground electrode like that.

I see three possibilities:

Foreign object (even loose carbon) thrashing around in there. I would rent a cylinder camera and look inside #4.

Really high plug temps. As a plug wears and the gap widens it requires a lot more voltage to jump the gap. More voltage= more heat. This may have caused the plug damage and damaged the coil also.

Severe detonation. Possible but unlikely. It would have to go on for quite a while to strip the electrodes like this. You are pretty in tune with your car and I think you would have noticed this.

Let us know what you find.

Yes a 225/45/17 tire will mount on your stock rim with better grip and no fitment issues.

I hope you find some clarity in this. Good luck and happy shopping!

Great to know, thanks! Would a 245/45-17 fit? It's 7mm talled, and a half inch too big for the rim, but oh so tempting for the extra width...

It might fit without rubbing but there are downsides: You will need at least an 8" wide wheel to get the benefit of the wider tread. The taller tire may disturb your PSM/ABS because the rolling circumference is so different than your rears. Hydroplaning through standing water will be much more likely with a 245 up front. There is also an issue with failed power steering systems on tracked cars with 245 tires on the front.

The tried and tested sizes in 17" are 225/45/17F, 255/40/17R for street use and Boxster spec racing.

Or a track tool with 245/40/17 all around. (Not recommended for a novice as the rear of the car will rotate more easily and hydroplaning is more likely in the rain.)

Ok. Now you have reams of raw tire data. Time to apply this data to your driving habits and pick a winner. All tires are a compromise. There is no 1 tire that does everything well. All have a mix of grip, longevity, road manners, noise, and price. Here are three driver profiles you may find useful:

Type 1 Driver- Car is a daily driver doing 10-20k miles/yr. Cost, longevity, and road manners are more important than ultimate grip. Nexen 3000, Sumitomo HTRZ III, or a performance all season tire would be a good choice here. They don't cost much, have good grip, ride nice and last a very long time.

Type II Driver- Car is a weekend joyride with occasional Auto-X, track days. 5-10k miles/yr. Max grip and road manners are more important than cost or longevity. Mich. PS2, Bridge. RE050A Pole Position are good choices.

Type III Driver- Car is a weekend warrior. You live for track days, Auto-X and canyon carving. 3-6k miles/year. You take your track days seriously but don't want to drive around town on R-comp tires. Max grip is everything. Ignore the cost or longevity. You don't care if the ride is more harsh or a little louder. You are in a PCA points race in Stock class and you want to win. Dunlop Direzza Star spec, Yoko AD07, or Bridge RE01R, are your best choices here.

Yes a 225/45/17 tire will mount on your stock rim with better grip and no fitment issues.

I hope you find some clarity in this. Good luck and happy shopping!

A showroom stock PDK Carrera on comp tires took TTD at Streets of Willow against some well driven, well prepared race cars, GT3's, Lambo's etc. Scary fast!

What is "TTD" ?

TTD= Top Time of the Day. A significant achievement when you are rolling with GT3RS, 997TT, Fully prepared 993TT race cars, Lambo Gallardo etc.

What kind of supercharger?

In general A 3.4 is a different animal. Benefits of a SC on a 3.4 is nominal. A 25's and and 2.7's are probably interchangeable with some tweaks.

Regards, PK

Supercharger was made from TPC.I have a 2.7 2001 Boxster and they told me that supercharger was made for a 2.5 but the guy who sold it to me told me that is ok for 2.5 or 2.7.

Send an email to Casey at TPC and tell him what you have (part #'s). He can probably point you in the right direction. Maybe just a different bracket. As you know there is not a lot of room around the motor so a little creativity may be needed for a good fit.