Printable Version of Topic

Posted by: nine14cats Sep 23 2006, 09:33 PM

Im here at the PCA-GGR Time Trial at Thunderhill. Although windy in the morning, the track was awesome today...VERY FAST!....We are running the 2 day event in the normal "counterclockwise" direction.

My personal best is a 2:07 going this direction over the top with turns 5 and 5A. During the 1st session on cold as shit tires I burn off a 2:07. Hey...what's going on here? Could I be having one of those magical days. Session 2 I turn a 2:06.5. Now I'm thinking can I get into the 5's? I go out in session 3 and burn a 2:05.4!

So now I'm pumped..... I psych up for the last session and crank out a 2:04.3!!!!!! It was sooooo much fun!

Have you ever been in that zone where the car and you feel just right? My car never felt out of sorts, never out of control. Braking was perfect, the traction was perfect. And I could see the whole track in my mind turn for turn. I would approach sections of track and feel like it was slow motion. This is what you live for....

And from a great day comes the kind of stuff that makes you want to eat a gun.....

During the next few laps after I turn the 2:04, I'm hauling ass full throttle down the main strait and my motor let's go! I didn't have an over rev, the car's temps were fine and as attested by my laptimes, I wasn't having power issues.

I was full throttle and suddenly lost power. No metal to metal sounds, chunking, clinking. No oil dropping....motor is still bone dry. But it sounds like and feels like I lost compression in one or more cylinders. It sounds like air is rushing by something in the motor. I checked the motor oil and it is clear and clean, no bits. Anyone care to hazard a guess as to what happenned? I'm thinking top end somewhere, rings or valve related, but again there is not metal to metal sounds, only the sound of air rushing somewhere in the motor.

This is a cruel sport. Today was perhaps the best time I've ever had driving and it ends so terribly. Time to bring Fritz home and start the diagnosis. And I was leading the series in points. A DNF will most likely cost me my class win. I'm pretty bummed right now....

Bill P.

Posted by: grantsfo Sep 23 2006, 09:40 PM

Hope its not too bad.

Posted by: trekkor Sep 23 2006, 09:58 PM

Sorry to hear this, Bill.
I hope it is a simple and inexpensive fix.


KT

Posted by: nebreitling Sep 23 2006, 10:40 PM

happy to hear about the blazing fast times -- and sorry to hear about the mechanical!

as per the diagnosis: you just lost power -- but the motor still runs?

Posted by: nine14cats Sep 23 2006, 10:48 PM

Hi Nathan,

The motor still runs. No smoke from the tail pipes. Some "smokey" venting from the oil tank...

I somehow doubt it is a bad injector....not my type of luck....

Bill P.

Posted by: trekkor Sep 23 2006, 11:18 PM

Are you still up there?

Maybe someone can offer some help in the morning.


KT

Posted by: nine14cats Sep 24 2006, 05:49 AM

Hello Trekkor,

I am still here at Thill. I'll be watching the PRC qualifying in the morning and then I'll be leaving. Several people have offered to let me drive their cars to get points in the TT. I'm tempted, but the last thing I need is to have a mechanical in someone elses car, so I'm not going to do that.

Them motor has issues. Nobody at the track can help me with that.

Thanks,

Bill P.

Posted by: Randal Sep 24 2006, 08:51 AM

The Zone: It is a wonderful place.

A 2.4: WOW... that is smoking Bill. And counter clockwise as well.

The Motor: If it was the crank, a rod, piston or valve there would be carnage all over and you can tell by the noise when it happens.

This sounds like a top end issue where, as you describe, compression left the cylinder. So what you have are plugs, seals, injectors, rings and/or maybe, at the worst, a cracked or hole in the head.

Wondering if it's time to start measuring EGT.

I'm hoping for a minor issue that is easily fixed.

Posted by: trekkor Sep 24 2006, 10:33 AM

A leakdown test should be pretty telling.


KT

Posted by: sixnotfour Sep 24 2006, 07:02 PM

[quote]This sounds like a top end issue where, as you describe, compression left the cylinder. So what you have are plugs, seals, injectors, rings and/or maybe, at the worst, a cracked or hole in the head. [/quote)

or piston

Posted by: Dan (Almaden Valley) Sep 24 2006, 07:25 PM

Sorry to hear about the motor problems Bill. Maybe a blown out spark plug?

Hopefully an easy fix

Just when you were starting to feel the track. Memorizing the turns and seeing them in your mind as you attack the track makes it all the more fun and fast.

I have been telling my students to do just that for years.

Posted by: drew365 Sep 25 2006, 09:25 AM

Bill; I'm sorry to hear about your motor. Sounds like you were getting into a good flow with your driving, having down time with mechanical problems makes it tough to improve the driving. Coincidentally, I have my own ecstacy to agony tale from Buttonwillow this weekend that I will post later this evening, and I have pics unfortunately.
BTW 2:04 is smoking! Good going.

Posted by: smdubovsky Sep 25 2006, 09:47 AM

Bill,
Lost an ignition? The 3.6s can run though well down on power if the dizzy belt breaks or one of the ignitors dies. Doesn't explain the noises though... Pull one ignitor connector and try to start the car, replace, pull the other and try to start again. If one wont start/run, it at least isolates which half of the system isn't working.

I've lost a plug wire on my 911 motor before too (popped off in an autox). Way down on power, but it was still close enough to keep the idle ok. Must have still been arcing to the plug cap, but under load was missing. It actually caused a faint air leak sound from the cooling air coming out of the plug hole.

SMD

Posted by: nine14cats Sep 25 2006, 09:58 AM

Thanks for the tips guys. I'm leaving on a trip to New York tomorrow, so I won't be able to play with the car until I get back. I plan on going through every plug and connector again, open the disty up to check the belt and also pull and test every spark plug.

The car starts right up and idles, but it has no power and sounds like a giant air compressor. I'm targeting the 2nd weekend in October to pull the motor if I have to. The first weekend I'll only have time to fiddle since I have other things going on, but by mid-october I should be moving towards a fix.

Andy,

Sorry to hear that you had the Ecstacy and Agony feelings as well. I have never had so much fun as this weekend. And the lows were pretty bad too, but I'm starting to get a little jaded. I'm recovering quicker and quicker.....

Bill P.

Posted by: maitaiken Sep 25 2006, 11:05 AM

Bill sorry to hear about having "bad" racers luck. I recommend the first thing to check is to see if both cams are turning. Pull off the intake covers and rotate the crank by hand. This will eliminate the dreaded broken timing chain issue. If all is OK then procede checking the electrics. Good luck.
KM

Posted by: nine14cats Sep 25 2006, 12:11 PM

That's a good idea. It's been suggested to me that my timing gear may have slipped on the indexing of the camshalft. Supposedly 993 motors do not have a keyway on them and are a clearance fit. The car was running great right before the issue, so the hypothesis is that I may have had a timing slippage and bent some valves....

Lots of scenarios to check....

Thanks,

Bill P.

Posted by: KenH Oct 3 2006, 10:09 AM

??

Ken

Posted by: nine14cats Oct 3 2006, 10:22 AM

Hi Ken,

I haven't looked the car over yet. I was in Texas for a week, flew home and did the TT, then flew back out for another week in New York. This weekend is the Honey-Do list, so I can actually start playing with Fritz on Wednesday, October 11th....

I'd like to diagnose the problem and go forward.....but I gotta do my chores....

Bill P.

Posted by: Randal Oct 3 2006, 05:01 PM

Wednesday, October 11th....

That is a good day to begin, also my birthday ----