The lessons we learned after our C5 Corvette's engine exploded

J.G.
By J.G. Pasterjak
Jan 1, 2024 | Chevrolet, Corvette, c5, engine, Project car, C5 Corvette, Blown Engine | Posted in Features | Never miss an article

Photography Credit: David S. Wallens

There’s a sound that, even if you’ve never heard it before, is instantly recognizable as bad. Worse than a too early alarm after a rough evening, a screaming baby on a plane, or your drunk uncle droning on about how the “real” government put chemicals in his soup to turn him into a zombie, this automotive equivalent of the shart …

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Comments
Floating Doc (Forum Supporter)
Floating Doc (Forum Supporter) GRM+ Memberand UltimaDork
1/1/24 9:04 a.m.

The timing of the failure is ironic, but the duration of the time this obviously defective rod survived surprises me. Were those stock rods? GM began improving the quality of their rods as far back as the vortec 350 truck engines of the late 90s, and the LS bottom ends are well known to be very robust. However, for an endurance race car, I would expect an aftermarket rod would be used.

I really liked this car.

Pete. (l33t FS)
Pete. (l33t FS) GRM+ Memberand MegaDork
1/1/24 9:44 a.m.

Interesting.  There was a spate of LS1 and LS6 engine blowups on track where the PISTON turned into granola and the free swinging rod and wristpin beat the cylinder wall apart, sometimes clear through to atmosphere.

 

It is hard to do a postmortem when all of the metal bits are Grape-Nuts and they are thoroughly distributed to the other cylinders and the ground.  I am of the mind that those failures probably started with dropping a valve.

 

My favorite carnage photo was intact piston rings resting on the passenger side control arm of a CTS-V.

CrashDummy
CrashDummy Reader
1/1/24 11:11 a.m.

If this is the end of the project, what was the final cost of the build? 

OHSCrifle
OHSCrifle GRM+ Memberand UberDork
1/1/24 11:12 a.m.

I am fascinated by the photo of the entire driveline dropped out of the bottom. 

RacingComputers
RacingComputers GRM+ Memberand Reader
1/1/24 11:20 a.m.

WOW    We saw a lot of oil Pan Failures in NASCAB 

 

As mentioned earlier it is hard to determine where things went wrong with all the bit and bobs of metal scattered around.

 

Good luck

Billbagley
Billbagley New Reader
1/1/24 4:44 p.m.
  • Back in the late 60 I had a brand new Plymouth.   318 automatic Most of the miles had been put on, 700 from Dallas to Amarillo, couple of customers aboard heading for a favored lunch stop/watering hole. Heard a quick clunk, a  shake, looked in the rear view mirror? What did I run over? looked in the mirror Identifiable transmission parts were bouncing all over the street.  

Did  not end that quickly though, flew home, Chrysler would only fix it at there leasure   4 weeks +-,  ,the case was not broken, they "repaired" it, no compensation, no transportation etc,  memory warrenty then was maybe 1000 miles. 
Never darkened there show room floor since.

The world has changed in many was for the worst, but in the case of Co s standing behind the product mostly better!

gzuckier
gzuckier New Reader
1/1/24 4:46 p.m.

You never know.

The laws of physics say that a part will break as soon as the stress on any point is greater than the strength at that point. And yet, things break in half sometimes just because you looked at them hard, instead of when they're being beaten to death. 

I snapped an axle half-shaft on a Civic once. Doing about 5 mph navigating out of the parking lot at work. 

JG Pasterjak
JG Pasterjak Production/Art Director
1/1/24 5:13 p.m.
CrashDummy said:

If this is the end of the project, what was the final cost of the build? 

It's a tricky tickertape because the natur eof projects is ccasionally doing stuff multiple times until you get it right, and none of those times are free. 

You could probably duplicate the car pretty easily for under $40,000, though. 

JG Pasterjak
JG Pasterjak Production/Art Director
1/1/24 5:17 p.m.
Floating Doc (Forum Supporter) said:

The timing of the failure is ironic, but the duration of the time this obviously defective rod survived surprises me. Were those stock rods? GM began improving the quality of their rods as far back as the vortec 350 truck engines of the late 90s, and the LS bottom ends are well known to be very robust. However, for an endurance race car, I would expect an aftermarket rod would be used.

I really liked this car.

Yeah that motor had been through a lot by the time it broke. I'm not sure whether the failure means the rod was stronger than I gave it credit for despite a defect or if it just had a short life expectancy at high load. I tend to think the former, since I rarely hear about failures like this in these motors.

And, yeah, I really liked it, too. It'll probably be a while before I build something this fast and easy to drive again.

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
1/1/24 10:10 p.m.

I missed this - why did you use a 525 hp LS3 that was built by a third party and not a GMPP crate? Were those rods "upgraded" or OE parts?

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