Engine Failure at speed... Options

[Cracker]

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! (IMG:style_emoticons/default/biggrin.gif)

Cheers!

Tony


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




My son came in from college - great memories at the track with him!

[Cracker]

Chris: Here is what I know now as I piece together what transpired...I have the entire video from last Sundays fateful session. On the outlap, I know see my pressure gauge fluctuating - only into and through corners though. I am not reading gauges at this point and had positive (albeit slightly lower peak pressures) on the straights. The damage must have occurred on one of the Saturday afternoon sessions but I was not running my on-board video then.

The suspected cause: I am at fault any way you slice it: I use Joe Gibbs Racing oil and it has a minimal life expectancy. I believe I pushed that limit too far, coupled with a slightly low oil capacity ~ about 1 inch low on my dry sump tank. I cook this oil and believe the root cause was being too greedy and certainly should have swapped the oil before this weekends event. I do not repeat critical mistakes and will make sure protocols are in place so this doesn't happen again. Obviously.

I have always toyed with the idea of a high-er revving LS7 - a de-stroked over square build that can handle about 1000 more rpms. You have to run a dry-sump system (check); You have to be a little crazy (check); and it really has to be professionally built (check). No guarantees but I'll be seriously looking at this as an option upon the rebuild. It will (maybe of course) have Jesel rockers, approximately 375 ci and H-beam
Oliver rods. I already had this engine priced out a couple years ago... (IMG:style_emoticons/default/rolleyes.gif)

I'm pulling the engine by weeks end and have it in pieces next weekend. Thanks for the well-wishes and kind words of encouragement guys! Hey Chris...can I borrow 20 grand? (IMG:style_emoticons/default/beerchug.gif) (IMG:style_emoticons/default/biggrin.gif)

Kent: The engine has seen two-years of track use and just a small amount of street-driving. Given all systems working well and as expected a major refresh would have been scheduled every 7-years (rings, bearings, etc). I plan on replacing valve springs every 12 weekends which equates to about 2.5-3 years worth of DE's with my schedule.

Tony

[bulitt]

Chris: Here is what I know now as I piece together what transpired...I have the entire video from last Sundays fateful session. On the outlap, I know see my pressure gauge fluctuating - only into and through corners though. I am not reading gauges at this point and had positive (albeit slightly lower peak pressures) on the straights. The damage must have occurred on one of the Saturday afternoon sessions but I was not running my on-board video then.

The suspected cause: I am at fault any way you slice it: I use Joe Gibbs Racing oil and it has a minimal life expectancy. I believe I pushed that limit too far, coupled with a slightly low oil capacity ~ about 1 inch low on my dry sump tank. I cook this oil and believe the root cause was being too greedy and certainly should have swapped the oil before this weekends event. I do not repeat critical mistakes and will make sure protocols are in place so this doesn't happen again. Obviously.

I have always toyed with the idea of a high-er revving LS7 - a de-stroked over square build that can handle about 1000 more rpms. You have to run a dry-sump system (check); You have to be a little crazy (check); and it really has to be professionally built (check). No guarantees but I'll be seriously looking at this as an option upon the rebuild. It will (maybe of course) have Jesel rockers, approximately 375 ci and H-beam
Oliver rods. I already had this engine priced out a couple years ago... (IMG:style_emoticons/default/rolleyes.gif)

I'm pulling the engine by weeks end and have it in pieces next weekend. Thanks for the well-wishes and kind words of encouragement guys! Hey Chris...can I borrow 20 grand? (IMG:style_emoticons/default/beerchug.gif) (IMG:style_emoticons/default/biggrin.gif)

Kent: The engine has seen two-years of track use and just a small amount of street-driving. Given all systems working well and as expected a major refresh would have been scheduled every 7-years (rings, bearings, etc). I plan on replacing valve springs every 12 weekends which equates to about 2.5-3 years worth of DE's with my schedule.

Tony

You are running an oil accumulator? Can't remember. Maybe an additional pressure sensing valve set lower than the accumulator valve to kill the engine prior to starvation next time?