VIR with PCC-Audi - Do you believe in the Tooth Fairy?

[WillM]

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Link to video below

This was my first trip to VIR.
We had an ominous start, and I had some car issues that cut into my track time.
These are the last laps I ran though I expected a few more sessions of seat time.
Unfortunately, the metal-on-metal grinding heard during the last 1/2 of the last lap on this video put an end to those expectations.

Tranny fluid was drained today and a bunch of gear teeth fell out.

Anyone know if the Tooth Fairy will accept 'em? I'm putting them under my pillow. Here's hoping she brings me a new transmission!

[Chrispy]

Ouch, sounds expensive. Worse was that it ruined your track time.

What happened to your AFR gauge just after the 10 min mark?

[WillM]

Ouch, sounds expensive. Worse was that it ruined your track time.

What happened to your AFR gauge just after the 10 min mark?

It went nuts. Error 9 I believe, which I think means it over heated. Those sensors last about a year in a track car, so going bad at the end of the season is about right. )

Could be that the sensor wants a heatsink.

[naschmitz]

You certainly were doing better on those technical sections than I was -- I was relieved to see that the red car holding you up wasn't me!

[cfossum]

That's too bad. Long trip for 25 laps.
At the 13:12 mark, the shift into third sounded a bit chunky (kinda like the lemons car did when the clutch failed). After that, some more chunking sounds occured on their own, then a chain reaction followed. Your car executed its failure with proper placement on the track though, allowing you to make your way comfortably into the pits.
At least it isn't the beginning of a season. So, did the tooth fairy arrive?
-Carl

[WillM]

You certainly were doing better on those technical sections than I was -- I was relieved to see that the red car holding you up wasn't me!

LOL! I was bummed to see you leave early on day 1. I was hoping to catch up a bit on and off-track. I was kept pretty busy with students on day 1 though. I'm glad we got to talk a bit on Saturday AM and in the afternoon though.

We should plan a semi-COM event at VIR. We could pick a track event that doesn't conflict with a COM event, and make a plan. I don't think it would take a lot of arm twisting to get a bunch of us down there.

[WillM]

That's too bad. Long trip for 25 laps.
At the 13:12 mark, the shift into third sounded a bit chunky (kinda like the lemons car did when the clutch failed). After that, some more chunking sounds occured on their own, then a chain reaction followed. Your car executed its failure with proper placement on the track though, allowing you to make your way comfortably into the pits.
At least it isn't the beginning of a season. So, did the tooth fairy arrive?
-Carl

Yes, good timing and placement for the failure! End of the season and a couple of turns just before pit-in!

So far, no love from the Tooth Fairy!

Carl, I hadn't even noticed those sounds in the video. There are so many plings & bangs heard inside of my car and in the video, though I must say that the video filters out a lot of 'em. When the tranny failed, from inside the car, there was no warning. The shifts never felt any different than usual. I was getting nervous about the engine & electrical system as the session progressed. First the O2 sensor started going crazy, and then the OP gauge was dropping into the green zone. I had similar symptoms the day before, and replaced an alternator overnight, which fixed the problem. You can see in the video that I reach over to the data display a few times to get it to display voltage. The That said, there are a few more "chunky" sounds earlier in the video. Most notably at the end of the back straight at around the 11:20 mark. When the tranny failed, I thought it was the engine, then I thought it could have been the clutch. The drive train only locked up at the end of the day, just as I pulled the car onto the trailer. Even then, I clutched-in, rolled back, and the tranny started working fine. Very odd. The transmission still shifts fine.

The car sees sustained 8000+ RPMs at this track, more than any other track I've run at. Gordon suggested that the problem is due to vibration, and I think there is a lot to that idea.

The tranny was rebuilt 2 years ago, however with stock internals. Next time around I'll either cryo/REM a fresh set of gears or go with an aftermarket set.

[breakaway500]

I'll bet it's a third gear failure. Happened to me at NHMS in '08 coming out of 12,just as I was reaching for 4th. Same scenario...kind of a crunch-bang sound followed by clanky-clank noises. I though it was my differential,till I tried it in first and the car moved fine. The only gear missing was 3rd. I was told by Flyin-Miata third is the most stressed,but weakest gear cluster in the stock Miata 5 spd.

Oops..

I had FM install a close ratio Quaife 5 speed gearset.Expensive,yes..but it has 5 perfectly spaced gear ratios and shifts flawlessly.Best tranny I have ever used. Not to mention much stronger than factory.

I consider myself lucky the tranny did not lock up the rear wheels at 90ish....yikes!

Count me in for a VIR trip.Paul Newman said it is "Heaven on Earth".

Besides...I would love to see the Ariel Atom factory, which is right on site!

[paultg]

Will, these might not be as robust as you are looking for now, but thought i'd share the link. Maybe a decent starting point:
http://www.planet-miata.com/index.php?s ... em&idn=209

Paul G.

[n1gzd]

just watched the video. I could hear the crunching metal noises. Question, why did you keep driving after you know there was a problem? Did figure that the damage was done and (nothing to salvage)?

Rebecca

[WillM]

just watched the video. I could hear the crunching metal noises. Question, why did you keep driving after you know there was a problem? Did figure that the damage was done and (nothing to salvage)?

Rebecca

I kept driving because:
1. I was close enough to pit-in that I felt making it to pit-in was the safest & most expedient thing to do - both for me and everyone else on the track at the time. There aren't any 'good' places to safely pull-off between where the failure happened and pit-in.
2. The flaggers were not giving any direction (no flags) and didn't even seem alarmed.
3. Aside from the noise, the car seemed to drive normally.
4. A scan of all but one of the gauges (the O2 gauge) showed good reading (oil press/temp, water temp, etc).
5. The loud rattling & crazy O2 sensor led me to believe that the problem was in the exhaust (a hole in the header/collector).

[CP]

I've wasted 3rd gear in 3 transmissions over the last 4 seasons and the current trans is beginning to show signs of the same affliction. None have grenaded on me but they all began to "ker-chunk" when downshifting from 4th to 3rd. You can usually feel the change before they go kablam, or so I've been told. And I'm one of the guys that's "easier" on these Mihotter trannies (no slam shifting here). The 2-->3 upshift coming up the hill out of T3 is usually the spot where these things die.

[paultg]

Will, saw this online and thought it might be of interest:

http://forum.miata.net/vb/showthread.php?t=441757

[CP]

A $3600 tranny in a Miata? Most donor cars cost less than that. I'll take my chances with 6 stock transmissions instead.

[zchris]

Cy, you have to weigh the overall cost of an event. If you travel to VIR and have a $300 entry fee, you could be spending $1200 plus for a weekend. If your weekend ends on lap 3, and this has happened to me, that $3k dollar tranny is now not such an extravagant item. And if it survives 4 times as long, it almost pays for itself. Remember the saying "penny wise, pound foolish". You will find many racers that have the same highend gearbox for 15 years. I'm not advocating spending money you do not have. Just not throwing money away on an ill prepared car. And in Wills case the tranny is doing a job it was not even dreamed to do by the designers.
Chris