Well, it is not "if an issue will occur on a race track" but rather just a matter of when! Sunday morning was gorgeous at roughly 65 degrees and cloud cover. The grip was surprisingly good and the dense, cool-ish air enabled the engine to run really strong.

The night before, a few of us "walked the track", taking in the nuances that really can only be seen on foot, kneeling down and taking our time. More drivers should take advantage of this to become more familiar with details that are completely missed behind the wheel of a car. Anywho...

We were discussing an asphalt patch that is on entry into the downhill section to turn 10a...specifically, how the patch had an elevated center with ramps on either side. A friend mentioned, "hitting that at speed would cause quite the jolt to the car and driver". Also of concern was the potential loss of grip and the unsettling of the chassis at such a critical point. He was correct as I bore out witness the next morning.

We have still not found the smoking gun and only hope it is not internal; the top-end is fully functional with each of the valves operation correctly. The engine does not turn over quickly and that obviously is a cause of rather great concern. I have been doing track events for some time now, over 15-years, and have never encountered such a failure.

I guess I can say...enjoy the failure at my expense.

PS: Talk about cutting it close...lose an engine down the hill; try to jump start the engine at turn 10a and just BARELY make it up the hill over T11 to glide back to the hot pits. Whew - that was close!

Cheers!

Tony


https://www.youtube.com/watch?v=VRvMJeXJxTQ


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My son came in from college - great memories at the track with him!
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Glad no incident with blown oil all over the place.

Hope the damage is minimal.

Nooooo! Sorry to hear about this, Tony.
Let us know what happened.
Fingers crossed it's something simple.

I didn't hear any catastrophic noises and it went dead quickly.

The talk about the rough patches on the track, was that just setting up the story or you thinking a bump could have knocked something loose? I sure hope it electrical / ignition and not mechanical.

Wow Tony, that does seem odd. Sorry that happened but hopefully it won't be much to correct.

Time will tell but it is weird as hell that the moment I hit that damn patch my engine cut represented by the shift lights. That is no coincidence - no way! I am hopeful that it just knocked the female clip in the fuseblock loose or something stupid like that - I am at least entitled to dream!

Thanks to you'all for your well-wishes! The engine was freaken' strong and that was my first hot-lap! I was gunnin for a record this morning (maybe it was good thing/Higher-Power at work)...to save my A$$!

T

Electrical?

Went quiet quick and no mechanical noises...

Deja Vu, Rob. Hope it's good news.

Electrical....

We not only are living vicariously through your racing exploits, but we are also corporately sending good vibes via the Porsche Gods!!!!

Hoping it's something simple.

Dang your car is fast! Well, you couldn't have had a better and safer exit off the course. You get it fixed, hopefully inexpensively...

Looked electrical, could't see all the gauges, but could be an inexpensive fix. Hopefully

Geez I miss RA....mine's still in the $hop with mechanical....not electrical.
Looks to me like the fuel pressure gauge stayed powered til you switched off the fuel pump, so prolly start looking at ignition power circuit at the first connection. If you're on MSD, there may be an in-line fuse that can shake...after all that has solid power a wild guess may be the crank position sensor just gave up on you.

Again, thanks for well wishes!

John: My electrical circuit isolates each particular "leg" so the engines ECU could be affected and have no bearing on my switch box or dash. The tach-signal, which the shift light is getting its power from, is provided by the ECU - I did not have this video until last night or we might have been able to get the car back on the track.

PS: I failed to mention this but my good friend "SixAddict" aka Terry O'Toole was there all weekend doing a great job with his Six! One session, he was black-flagged for a "sagging (stinger) exhaust; he came in and replaced the missing bolt and STILL finished the damn session! Amazing and crazy 914 gumption on display - love it! He even overcame a larger obstacle earlier on Saturday but I don't want his head to swell - it was impressive.

Tony

Yikes! I hope the ultimate cause/fix turns out to be straightforward and not too costly!

My last "oh crap, what now" moment luckily was just a fuel pump power connection that "mickey mouse" hadn't wired very well...took a while to isolate that sucker though

Chris: Thanks. The dynamic I find interesting with these issues is even though I lost an entire day on track - you grow to understand that when cars are pushed on track (especially 47-year old teeners!), crap IS going to happen. There was no crying, temper-tantrums, or other ridiculous behaviors on display...even if the engine is blown. After many, many years of doing this track-thing - much like yourself - you mature in the hobby. It is all still worth the thrill and cost of admission - to me! Cheers.

Tony



Here is the still-shot from another video immediately prior to the failure...I had to get off throttle at this point but without that damn bump I'd carry throttle to the billboard on the right.

Pucker Factor = Yep!
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I didn't hear any bad mechanical noise, here's hoping for electrical as well.
Customers and the few I've blown the explanation was always "there was a bad, bad noise".

Hi Tony,

Thanks for the posting. As one of the guys said I live the excitement through you. I will say as a person that has blown 2 water cooled engine’s over my life that my bet is this is minor and not a hard engine part. I hope you get lucky.

Bob B

I would also like to venture that the lack of a mechanical noise is a good thing. I would also like to chime in about the importance of walking or at least driving slowly around the track to become familiar with the nuances as you mention. Its a good reminder to bring up once in a while.

Sorry to hear, hope its a quick fix. But man you have one BadAss 914!

Define cranks slow, does it constantly crank slow ( too much friction overall ) or does it spin fast between compression strokes then goes slow over compression ( like the timing is advanced too far ) ? Did you turn the motor over by hand with plugs in and out?


This is a V8 Chevy LS as noted in the vid title correct? As an initial test, I'd check valve events against crank position to make sure they are believable in case a timing chain hopped over. ( this usually results in low compression however )

It is possible for an engine to overheat, pistons swell and grab the bores. This does not make any noise but power does noticeably drop off over a few minutes.

If you instantly lost oil pressure, the bearings could melt and grab the crank especially if they are aluminum. This causes surprisingly little damage as the crank does not get a chance to be scared up. ( think gluing the rods to the crank. ) If this occurred, I'd check the rods for bending.

I would think the first thing to do is check for spark before digging into anything deeper. But yeah, the slow cranking thing needs an answer (unless the electrical fail means low battery or something.)
I figure Tony knows how to troubleshoot though. Good luck.

That car is amazing. I hope it's nothing major.

Thanks for that thoughtful insight...just to clarify my claims of regarding the cranking. It was our initial thought that something bad happened on the bottom end; maybe a timing chain for instance. I pulled the valve covers to inspect the rockers - all valves are properly activated. There is no way the timing chain jumped a tooth on this motor...we are running a double roller Katech unit with aftermarket gears. I called the engine builder today to confirm this and he agreed. This means the timing chain failure is out - big deal since that tears up heads, pistons and cylinders. The engine didn't turn over nicely with or without plugs but the battery was also compromised and registered 10.5 volts. I am going to check spark but already know there is none. If that IS the case, I will check power on the ECU circuit and determine if my hypothesis is true. If so, I will install a jumper wire on that circuit to see if we light the shift light with ignition (and fuel pump) - should fire. I really believe the root cause is the female fuse block receptacle has "slipped" down and cut contact with the fuse. Just a hunch since we had the same thing occur with a bank of coil packs earlier this year.

Tony

On a totally unrelated topic/video...I came across this just now - its worth the time. Sweet driving and an 8000 rpm 3.0 with a slick close-ratio trans to boot! Enjoy.

T


https://www.youtube.com/watch?v=bgBcaKPhKbI

If your battery is 10.5V is your alternator charging? If voltage dips too low, typically in the 10.5VDC, many ECUs (high-end aftermarket ones at least) will start cutting as a self-protection method to avoid over current faults on the coil drivers.

Hmm? Solid observation Sir...now that you say that, I noticed a slightly "jumpy" water temp gauge the day before that was unusual - it eventually settled down. I bled the cooling system thinking it might have been air in the line - took a little water. I recall, however, seeing my volt meter show just under 14 on Saturday. Definitely something to look at for sure. Thank you!

OK: I can definitely see my volt meter over 12 at the time of shut-down...it is to the far left of the dash. Hard to see..

Tony



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I've been burned by that a few times so I figured I'd throw it out there. Once after loading a car on the dyno and planning to spend the day there.

Ahh, I didn't even notice it in the video. That wouldn't seem to be the issue then. Your slipping fuse connection seems like a good thought. Definitely seems electrical based on the video.

The electrical narrative is boosted by the loss of power to "all things powered by the ecu" - that are visible from the onboard camera. The fuel pressure gauge is the white faced unit just to the left of the shift knob. I have fuel pressure indicated at about 10:30 (which is a correct and accurate indicator) and by the time I turn into 10a - it is at zero or 7:30. Conclusion: Either the ECU DIED at that moment or the ecu lost its lifeblood - power. I can only hope that there wasn't collateral damage caused by an abrupt engine cut...

PS: I thought I locked up the fronts again and you can see me glance in the rear view mirror - I was looking for a trail of smoke. Felt very similar to that prior experience but without the engine noise - it was kinda weird.

Tony

Millions of cars do that everyday

Only issue would be if you lost sparks at that RPM and it was still squirting fuel, which could be ignited by the cat, which I doubt you have, and burned it.

Awesome racing video, but boy does that look like a rough track to do a bunch on laps on.

I have a process and technique to slow the car - its not only the brakes that accomplish it...off-throttle at that speed with the engine cut is what I am referring too. THEN, I proceeded to shift through the gears, as I normally would - THEN, I tried to jump-start the engine just prior to turning into T10a - I used 3rd gear. It didn't catch and I JUST had enough momentum to crest the hill and on down to the pits. But you already knew all of that...

T

Tony,
I hope it is just a simple electrical problem

Your battery is either fully discharged or you have shorted a cell. ( Actually electrically shorted not an electrical "open" that many call "shorted" ) I have had batteries with a shorted cell crank all day but a bit slow and unable to properly operate a FI system. A fully charged "12" V with a shorted cell is 10.5 V.

Here is a handy chart to determine a lead acid battery's state of charge ( how full the "tank" is) . Note, this only works if the battery has been siting for 8 HR since the last time it was charged / discharged and the numbers can vary a bit. This does not test battery capacity, you need a load tester for that. ( how big the tank is )

Using an accurate digital volt meter, testing at the battery terminals.
12.66 full charge ( This is 2.11 V per cell )
12.42 75% charge
12.18 50 % charge
11.90 25% charge ( Go below this on a regular basis and the battery will degrade )
11.70 0% charge ( Go below this more than a couple of times and the battery will be damaged )

If feels to me like people are talking basic 101 with someone who is way past that. Surely Tony would have swapped batteries or hooked up to something before delving into such detailed meter testing. Don't you think? And hopefully that car isn't using a lead acid battery.

And stop calling him Shirley. . .

I don't know the OP, but I would not even try to crank an electronic FI engine if the battery was 10.5 V. With a carb engine you "might" have a slight chance of catching it.

Even if the battery had a shorted cell while driving, the alternator would keep voltage up while running so I'd tend to think the alternator quit charging and the car ran out of electricity.

I've seen ( and fixed ) too many cars that went from shop to shop without a positive result because the basics were missed / others assumed that so and so would have checked item X.

Its all good...keep it coming. We noticed voltage and went to cables. You never know WHO would be reading this and gain some benefit! Thanks!

Tony

I've had a few similar electrical mystery problems in the past. Car would crank but not start until you let off the key, and on that last portion of revolution of the motor, it would usuallly start. After that it would start just fine all day. Just that first start. Used a basic volt meter in the morning, battery was 12+ volts. Borrowed a load tester and the battery fell on its face. Seems letting off on the key lightened the draw enough that the aftermarket ecu saw enough voltage to operate- there just wasn't enough to turn it over and power ecu at same time. After a start and charge, you could generally start again with no problems or symptioms.

New battery solved that one. Took awhile to figure it out.

At an autocross the car just stopped dead mid run. No warning. No painful motor sounds. Rolled off track and hit the key- no fuel pump could be heard. Checked all fuses, all were good. Nothing looked wrong. Ran wires for + and - from the relay up to the pump. Maybe a wire had grounded out. Still nothing. Trailered it home. Next day found a 15 yr old crimp between a ground wire and ring terminal for the ecu had let go, and I lost ground to the ecu. No ground, no crank signal. No signal, the ecu would not trip the relay to power the pump. 5 minutes later it was all good again.

Not hearing the fuel pump was not the problem, just another clue. That I didn't see for what it was.

Electrical can by tricky. One clue can mask another problem and get you thinking the wrong way. You can have the answer right in front of you and miss it.

Based on no sounds of mechanical death, I'm thinking electrical also. Look at your clues carefully, test theories. My experience is that electrical issues are seldom a smoked board or other big deal repairs. Generally something simple- a battery or ground in my case.

Good luck, and great car. Fun to watch it eat up track. And whoever happens to be in front of you.

I don't know what gauge your cables are, but most consumer grade ones are more battery charging cables than true jumper cables.

The consumer stuff is 10 to 6 gauge with thick insulation and poorly connected copper plated steel jaws. High end cables are a minimum of 4 G with 2 or 0 G being even better and have well terminated solid copper jaws.

With real jumper cables, an engine should be able to be easily started without a battery in the car. If the cables can't do this, they are charging cables.

With the car running, the battery voltage should be in the 13.8 - 14.2 V range, I looked at the vid and it looks like you are at 12 V ( difficult to see ) , this is too low.

In any event, the battery voltage is too low, attempt charging then do a load test.

Busy work week! Normally the gauge reads right at 14v...I am not even pulling the car out the hauler until Saturday. My cables are CABLES...they were built specificatlly to be used on our 1100 hp/600ci mile car.

Tony

Update
Well...it doesn't look good. I checked power at the fuse panel and have ignition, fuel and spark - Hell, I got power everything. The engine started up and then died within seconds; a second attempt led to the engine dying even more quickly. After the third start (again having difficulty turning over but catches) it made a strange noise as it shut down - a rotational scraping type noise. I did not hear it the two times it ran.

At this point, unfortunately, I believe my original assessment at the track may unfortunately be true - something is likely wrong on the bottom end. Oh well.

One interesting observation: When the ecu primes the high pressure fuel pump the gauge will "hold" that pressure for startup; however, right now that pressure is dropping immediately after the pump cycles off. Hmm?

I plan on getting the car up on the stands tomorrow afternoon and pull the pan - I'll be looking for bits and pieces that shouldn't belong. If I have anything that warrants pictures I'll share the gory details.

Tony

Ugh - fingers crossed, my friend...

Before you pull the pan, pull the spark plugs and bar the motor over. For an engine to stall due to friction, you will barely be able to turn it by hand.

With this drop in static fuel pressure, you might have hydro locked a cylinder due to a leaking injector / manifold referenced fuel pressure regulator. This is a bit of a stretch given you didn't note any fuel smell / rich exhaust when it was running.

Given the battery voltage was so low on track , the starter may have stayed engaged while the engine was running. This would have out run alternator output discharging the battery. A failed lower end won't directly cause the battery to discharge.

Is the fan belt still driving the alternator?

I don't have a hydro locked cylinder...starting to suspect an oiling issue - sadly given the effort to build a package to avert this possibility. I noticed in my hi-rez video that my oil pressure gauge was jumping around - comparing it to my previous video's - it historically barely moves. Odd that there were no overtly noticeable noises audible from the the vid or from the my seat. Either way, that would be a fault of my own if that turns out to be the case - I should have caught it! There is no fuel smell at all; the plugs were showing a leaner condition but also shut down just off WOT on a 1/2 mile pull so to be suspected; both the alternator and dry sump belts are present; I had oil pressure all the way through shut-down. Hmm?

PS: I have had a hydro-locked engine once before; I bought it that way. The PO had let the intakes bolts loosen up and coolant "secretly" filled a cylinder. In that case, the engine would not budge since the coolant does not compress. I pulled the plug, drained and blew out the cylinder, tightened the intake bolts; it then ran perfect.

Also, the PCM fuse is giving me a 12.18 volt reading yesterday...I am also not ignoring your suggestions regarding spinning the motor but there is not enough clearance with it in the car.

T

My denial tendency causes me to think up some sideways causes, like the starter is hanging up....is it accessible? Good luck, Tony....

No, the starter isn't hanging but I appreciate the thoughts and idears.

Tony

Well, I have bad news (for me)...my original, trackside diagnosis and instinct unfortunately proved to be correct. Here are a couple of pics of what came out of the pan...

Tony

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Damn. The torpedos and the result. Way too shiny. I have been thinking that the only silver lining is that the hard work of building the car outside of the motor remains intact. From what I have seen it will be on the track again and not languish on jack stands. Good luck with the rebuilt or new engine.. As it seems from your post.
So you think the crank froze to produce the power loss?

Bearing material ?,looks like whitemetal and copper backing....that sucks big time,sorry for you Tony.
Hopefully you can work around this and get the worlds fastest 914 back on the track .

Ouch...

That's the 's alright. How many hours did that engine clock, Tony?