Yeah...I'm sure that happened...
Using the German torque method. Guttentight.

 

Oh wow that's hosed.

 

If you look closely in some of the pictures, you can see the crank pulley as it's running away

 

I assume the bolts just backed out rather than sheering?

 

No, they sheared.

--Ian

 

Did they all shear? I thought I saw one that wasn't there.

 

I've had those bolts vibrate out before. After that I started lock-tite'ing them in. At some point I upgraded to a higher grade bolt (10.something) as they were stronger so I could torque them tighter. Stronger bolts + red lock tite, never had one back out or break after that. I now have ATI damper so don't use them but that fixed my problem. No torque wrench, I torqued the new bolts to like 20 something foot lbs, basically to "I think another 1/4 turn would snap the bolt".

 

If they sheared, it's highly likely they vibrated loose, and the balancer started shaking which would easily shear the bolts.

 

One completely missing, 3 sheared. Definitely no locktite on the 3 that sheared.

He ran 2 more 20 minute sessions after swapping the balancer out. Like a boss.

 

And is now probably 3 hours behind me on the 800 mile trip home.

Bet those were OEM bolts. I have about 350 left from when I bought 4 100 packs instead of 4 bolts to replace mine.

 

Ed. Can I have that pulley. I'm making a sacrifice to the horsepower gods shelf in my garage. It has a piece of Laguna Seca you can take home too.

 

I talked with Savington at the end of the evening and he said that usually the problem is over torquing. The bolts stretch and are weakened, and then they break.

I definitely over torqued the ones I put in there after this mishap.

That being said, it performed great the last two sessions, and on the last session I set a new personal best: 1:49.4. Really really happy with it. I know there's a lot more time in the car and me as is (still braking too early at turn two and the corkscrew..... And turn 4) but car still runs. Made it 3 hours to Folsom staying the night at a friend's house, drive the rest of the way tomorrow.

Many, many pics and videos forthcoming. Wish me luck!

 

Wow dude, you knocked off 7 seconds! Was that still fighting the MS issues too?

Good luck on the trek home.

 

Thanks Brian! My best last year was a 1:54.xx and Saturday I did a 1:49.8, so picked up just 1/2 second.
I wasn't exactly fighting the MS issues anymore... Just running with a 5900 RPM rev limit, ha.

 

Did you try the high-rev thing again after replacing the pulley? Is it possible that the bolts had loosened enough for the pulley to wobble, and that threw off the crank sensor readings at high rpms?

Was this the pulley off the crashed car?

--Ian

 

Ed, you are a beast. You were averaging something like 7 seconds faster than me when we got out of traffic, but then you are also a much more aggressive/confident driver than I am. Plus I haven't been on a track in a year, and my car is all crazy different...

Now that I'm done making excuses, you are just a straight up better driver than me. I had a hard time keeping up. Good show sir

 

Indeed, that's a very respectable time. My best was 1:47.8, but that's with an extra 100 hp or so and RRs on the car.

--Ian

 

Crank signal is fine. Cam signal disappears at high rpm.

 

Have you ever looked a the cam/crank logic in the MS3 codebase? It's pretty clear that it wasn't originally intended to have both types of sensors and someone hacked in the cam sensor support. It can't tell the difference between a missing cam, a missing crank, or an extra crank signal, and an extra cam signal would be completely ignored. The composite logger isn't really definitive either.

All I'm really saying is that Ed had two failures that are vaguely related, and it's conceivable that they were actually the same one. Now that he's fixed the crank pulley it's worth doing the 6000 RPM test again before doing anything more to the cam sensor.

--Ian

 

Good idea. He should try that. Then we will check the VR pots. Then we will scope the cam signal.