2003 Porsche 911 Turb-OOOOH

Put my street brake pads back in this am and decided to see if some brake cleaner would make a difference on the front calipers.  Much to my amazement it did!  They're basically red again, only sign of heat is the white Porsche script now looks a bit yellow.  Sweet!

Also checked out my tires, I've got enough to make it the rest of this season, including the auto-x next month but I need to replace the rear tires next Spring.  Looks like the fronts are still in decent shape, so no need to get a full set.

potentially bigger concern is coating on the lug seats getting squashed out by lug torque and cyclic loading, thereby releasing torque on lugs, leading to fatigue failure of lugs and loss of wheel or worse.

not saying don't powdercoat the centers.  definitely saying mask the lug seats or dremel them clean before putting them on the car.

In reply to AngryCorvair (Forum Supporter) :

Good tip, if I get it done I'll ask the shop to mask off the lug seats...

Powdercoating can heat the wheels to 300-500F. That can alter the heat treatment of the aluminum. Personally, I wouldn't do it.

BTW, you should have pulled the center caps off the wheels before tracking- looks like they're pretty messed up now from the heat.

In reply to t44tq :

Center caps were like that already but yes, I should've removed them just to make sure one didn't pop out on track and get lost.

I'm really not worried about the heat.  Wheel companies powdercoat their wheels right out of the gate, it's a common process used to refinish wheels with no ill effects.

I don't know of any powdercoating that's heating to 500. 225 yes. 300 maybe. 500, definitely not. 

In reply to lnlogauge :

Urethanes are ~400°f, but 500 seems super high for a conventional powder system.

Annealing temp for Aluminum is like 600 to 800F.  Unless you go for a super high-temp powder-coat, they usually cook at around 350 F.  Totally fine.  My powder coat guy does wheels all the time.

I worked on some low temp powder coats - like 300 F flow temp - but those were for some carbon fiber parts so the lower temp was much more critical.

In reply to TVR Scott (Forum Supporter) :

Thanks, that's what I thought.  I'd never heard of powder coating negatively affecting the aluminum structure of the wheels

Sorry to start all this and disappear, I just saw the replies. 

I cannot tell you what PC does, but many years ago I saw one fail on an S2000. It was PC and it was on track. After that and reading I came to the conclusion it was not worth it. 

Yes OEs PC, but they can also control the process to a much higher standard. 

Here are some threads I found after googling "PC track wheels"

Thread 1 Rennlist

Thread 2 Rennlist

Thread 3 Rennlist

S2ki Thread

Again, you do you, I am not trying to be deterrent on your plans, just putting this out there as I seen them fail and it happened after I had VERY expensive set of BBS centers powder coated myself. 

On the flip side, I have been running the PC BBS centers on my e30 for about 8 years with no problems. They are street driven, but quite aggressively, still not track aggressive. No cracks so far and I inspect them every time they are off the car. 

So the last auto-x of the season was supposed to be today.  Yup canceled because 2020.  Sigh.  That's it for the season then, I washed the car, used Mothers R3 to remove the rubber clag marks and put it on the rack.  I put my stock wheels on it because I plan on getting the BBS wheels refinished gold this offseason.

Sleeping under a cover with the trickle charger on, see ya in the Spring.  My offseason tasks are to install the other two inserts into the exhaust to try and quiet it down some more, other than that, really nothing else to do...

OK, update!  I've been somewhat struggling with the volume of the Soul Performance exhaust.  It sounds wicked on the track and on short drives but on longer drives it's, well, intrusive.  The 20-30 year old me would've loved it!  The current 50 year old me is beginning to get annoyed.

I called Soul and they sent me those inserts, which seem to have helped a little, then I went to the track and burned them in and it sounds the same again.  Ugh.

The issue with this car is the stock exhaust is way to quiet and makes the car sound like a vacuum cleaner.  Most aftermarket exhausts are in the range of too loud to WAY too loud.  Europipe apparently makes an exhaust that sounds good and is quiet on cruise, but they rarely pop up used and new they're $4000.  Which is a lot to pay for an exhaust that I haven't heard in person and nobody locally has one for me to check out, I've asked around.  Of course I missed on on Rennlist this past Spring.

Playing around on Facebook last week I found a listing for an AWE-Tuning exhaust for my car.  Hmm, it's the newer single can version, which is better for power and has an integral crossover pipe, had cats and is a 3" exhaust.  I called AWE and asked them some questions, knowing that loudness is subjective.  They told me rather confidently that their exhaust would be more quiet than the Soul exhaust.  Makes sense, their's actually has a muffler vs the Soul only having bullet resonators.  AWE also has a dB chart comparing their exhaust to stock on their website, cool.

I got a good deal on the AWE exhaust, so I bit the bullet and bought it.  I'll install it and take some dB readings using an app on my phone, then drive it to the base this weekend for duty so I can see what it sounds like on an extended freeway cruise.  Whichever exhaust is more quiet I'm keeping and I'll sell the other one.  The muffler on the AWE exhaust is pretty damn small, so I'm curious to see which one is the winner.

Pics because everybody likes pics!

Not sure if it would work for this car but when I had my RX-8 I bought a used stock exhaust and opened the muffler up and reconfigured it. It was perfect. Loud when on the loud pedal but zero boom. Might be something to try if this doesn't work. 

Stock:

Not stock:

OK, this morning was it!  Time to swap the exhausts.  I'd hit the nuts that hold the cats to the turbos with PB Blaster last night.  Car up in the air, 13mm clamps hold my tips on, which I need to reuse.  Then 13mm clamps that hold the X section of the Soul exhaust to the bracket.

Time to get to the nuts on the cats.  Luckily I was able to get to all pretty easily, needed a 1/4" drive 13mm for one and a 13mm wrench for another, last two 3/8" drive 13mm.  Don't forget about the small 10mm bolt holding the heat shield on!

Ok, pull the exhaust down some so you have access to the oxygen sensors and pop them out with either a O2 socket or a 22mm wrench.

Pull the exhaust off.

Here's where I stop taking pictures because I was getting frustrated.  The AWE Tuning install instructions are available on their website, which is sweet.  What isn't sweet is the instructions are flat out GARBAGE.  They're basically a picture showing you how to assemble the bracket that holds the muffler to the car.  What they need to do is map out the order of how the parts are supposed to go onto the car.

IE:  First install muffler, then put primary O2 sensor in, rotate cat pipe in with heat shield in place, etc, etc.  Nope, none of that. 

I'm not sure I put it together in the proper order, I put the cat pipes on, then put the muffler on as I couldn't seem to get the cat pipes lined up into the muffler with the muffler in place first.  However I do think the muffler is supposed to go on first, then torque that muffler to the car bracket, THEN put on the cat pipes.

Anyways, after much cursing and struggling, I got it done.  Thank god I found the offset box end wrench my Pops gave me! A long 13mm gear wrench would be really helpful for this job and of course I didn't have one.

Exhaust is on the car!

Initial impressions, WOW!  MUCH quieter!  I took it out for a drive and it seems much more quiet too.  Unfortunately right as I left my neighborhood my check engine light popped on.  Car was still running well, I figured one of the O2 sensor plugs in the engine bay had gotten popped out since I dropped the exhaust and then removed the O2 sensors. 

Yup, that needs to go there...

Cleared the codes and the car is happy.

Here's a cold start idle with the air pump turned off.

They make some good stuff.  Been on fence about getting the AWE touring on my Q5.  Few guys on the Audizine forum have them and they sound very nice. Little pricey though, they are about $700 more then competitor exhaust systems

In reply to Placemotorsports :

The AWE stuff is super expensive.  All the exhausts for a 996 Turbo are $4000+ new, so I'm pretty happy I scored this one used off FB for a good deal.

In reply to docwyte :

Nicely done and lucky to find that one

So AWE, in their crappy directions, makes a BIG deal about torquing the muffler to car bracket to 30 ft lbs.  Earlier today I just got it good n tight with wrenches because I didn't think I could fit a torque wrench in there.

That was beginning to bother me, so I went back out there and tried to see if I could fit a torque wrench in there.  I was able to torque both bolts on the passenger side with some difficulty and the bottom bolt on the drivers side but there's NO access on the drivers upper bolt.

The muffler outlet blocks me from the front and the car itself blocks me from the back.  Got it as tight as I could with wrenches, that's all I can do.

I've owned 4 996s.  Two Turbos, a GT3 and a 99Aero Kit.  My current 996TT looks a lot like this one, and is stock, but the first one was a trackday beast and had a full aftermarket suspension and chassis mounts, GT3 front calipers with 350MM rotors all around, track seats and a roll bar.  The car was an amazing car to drive hard on track.  

My current $35K Turbo, bought back in June.   

In reply to Mikelly :

My former 670HP 996TT at its one and only drag event on Pirelli Street tires.

In reply to Mikelly :

Wheelie!!  My car is setup pretty closely to your first one, just no rollbar yet.

First evaluation of the awe exhaust for sound this am on my drive to the base.  It's much more quiet on cold start and at lower speeds around town.  Seems more quiet at freeway speeds as well.

i have an hour drive tomorrow, will know lore then

AWE exhaust is definitely more quiet on the cold start in the morning.  I'm sure my neighbors are appreciative. 

Those damn muffler bracket to car bolts are triggering my OCD.  One of the bolts on the drivers side didn't have a hex head, it had a phillips, which meant I couldn't get any torque on it.  One of my friends also pointed out I didn't have the exhaust tips perfectly centered, oh the shame!

So I put the car on the lift, removed that one phillips and put in a normal hex head bolt. Then tried to ninja in my torque wrench.  Thought I had it but then the nut started to spin and not tighten.  Sigh.  Removed the nut and yup, stripped!  So new nut on, couldn't get the torque wrench on, so just Hulk'ed the nut/bolt as tight as I could with two box end wrenches.

Centered the exhaust tips and I think I'm officially done screwing with this exhaust.  Supposed to snow today, hopefully will take the car out for a drive either Wednesday or Friday and make sure there's no resonance.

TVR Scott (Forum Supporter) said:

Annealing temp for Aluminum is like 600 to 800F.  Unless you go for a super high-temp powder-coat, they usually cook at around 350 F.  Totally fine.  My powder coat guy does wheels all the time.

I worked on some low temp powder coats - like 300 F flow temp - but those were for some carbon fiber parts so the lower temp was much more critical.

I killed a set of Kosei K1 racing powdering them.  All cracked on me shortly after.  Temp is one issue - the second thing is that you really should have a post powder heat run in the oven.  before welding aerospace components you typically run a preweld heat treat that softens misalign the molecules/grain in the metal.  Then following the weld work you go back for a post weld heat treatment where you realign the molecules/grain.  I have a theory that you should easily be able to solve the issue with a second run in the oven.

Nice writeup on the topic.  pre and post weld heat treatment writeup

In reply to 84FSP :

To be fair, plenty of Kosei K1's crack all on their own with the factory coating on them.