#7 piston disintegrated - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

Ret Grunt21 · 12-25-2017, 12:02 AM

So the L99 is toast. Thank god. Pulled the drivers side head and there is no piston in #7. Rod is gone too. No exterior damage to the block surprisingly. Going to pull the other head tomorrow and see if #8 suffered the same fate. I was cruising at 55 mph heading to the freeway to make the trip from Albuquerque to Tucson to see the folks. Thankfully I was only 3 miles from my house and not out in the middle of nowhere. Time for an LS3 and some goodies in it!

SS PANTHER · 12-25-2017, 01:03 AM

I’m in the same boat. Cats plugged on my supercharged L99 and damaged the ring lands on 7&8. Going forged internals with new cam and valve train. L99 sucks. Powered rods, hypereutectic pistons, nodular iron crank and lousy lifters and valve train. Hindsight is 20-20. If I would have known where I was going I would have bought the ZL1. Good luck with your rebuild.

christianchevell · 12-25-2017, 09:21 AM

SO your not using warranty...? Its totally not normal to have piston blow apart...and anyway for modding the new ls3 style of the GMMP ported heads for about 1400$ come with hollow stem intakes that l99 engines don't have, sounds like two cases of bad luck as many who do FI don't do cats as that's when they have the chance to screw the pooch from melt down due to the high fuel use ......its fine line with cats to not dump extra fuel and then on the other hand not use too little to run lean... Good Luck to you both and Merry Christmas. Crap Happens....

Olddudesrule · 12-25-2017, 10:44 AM

So what do you think caused it? Engine modded at all. I to have a 2014, and it's been bullet proof so far. Just finishing a LSA install, and am obviously concerned about getting a good, conservative tune on board.

Bo White · 12-25-2017, 01:07 PM

What mods?
Depends on what went first. The chicken or the egg. Most of the time its hard to tell what failed first. The rod or the piston.

Bo White · 12-25-2017, 01:09 PM

Most of the time its the piston if its in a million pieces. If the piston is in large pieces then more than likely the rod failed. Not always the case but rule of thumb.

Ret Grunt21 · 12-26-2017, 12:29 AM

Well I finished the autopsy so to speak. I’m leaning toward piston failure. Once I pulled the passenger side head, the piston was cracked. So #8 May have been the bystander on this one, and that rod broke too but up at the wristpin end. #7 rod and piston were totally gone. The only mods I have is a CAI and tune. There was a knock coming from the engine for a while and I was thinking that it was a failed DOD lifter. Pulled them all out and they were all good. Plus the number 1 intake pushrod was bent. I bought it used with 29k on it. Plus I found an aFe plastic sticker wedges between the front sway bar bushing and bolt. So the previous owner did something. Also looking at the other cylinders and there still is a crosshatch pattern but the walls appear to have a lot of heat scarring. Not normal. I’m thinking the previous owner put nitrous to it. So basically it was due to fail.

Ret Grunt21 · 12-26-2017, 12:33 AM

#8 piston and what’s left of #7 piston and half of the rod that I could fish out through the cylinder.

Olddudesrule · 12-26-2017, 07:55 AM

Man, that's some ugly physics right there! Glad you can take it in stride. Opportunity for a great build I guess.

Bo White · 12-26-2017, 08:24 AM

Is the block hurt?

NC_SS · 12-26-2017, 10:20 AM

I'm gonna be really surprised if there is no damage to the block

That's really nasty, I don't think I've ever heard of a mostly stock L99 popping a piston before

I've read about lifters going south but not full piston destruction

Reaper85 · 12-26-2017, 10:22 AM

How long have you had the car? Did it come with any warranty from the dealership you got it from?

NC_SS · 12-26-2017, 10:24 AM

he said it's tuned, so there is no way he will get a warranty claim out of GM lol

Ret Grunt21 · 12-26-2017, 10:39 AM

Externally the block is fine, but that doesn’t mean anything. I haven’t pulled the short block yet. When I do pull it I’m not going to tear it down and look. Not going to use this block as it’s not worth the risk after this kind of incedent. Best to get another one and start from scratch on the build. By the way, Bo, I read you Port TB’s. Since mine isn’t in use, I’d like to use your services.

12-25-2017, 12:02 AM	#1
Ret Grunt21 Drives: 2014 Camaro SS Join Date: Jun 2017 Location: Albuquerque NM Posts: 12	#7 piston disintegrated So the L99 is toast. Thank god. Pulled the drivers side head and there is no piston in #7. Rod is gone too. No exterior damage to the block surprisingly. Going to pull the other head tomorrow and see if #8 suffered the same fate. I was cruising at 55 mph heading to the freeway to make the trip from Albuquerque to Tucson to see the folks. Thankfully I was only 3 miles from my house and not out in the middle of nowhere. Time for an LS3 and some goodies in it! Attached Images

12-25-2017, 09:21 AM	#3
christianchevell old school chevy rodder Drives: 2013 2SS/RS Manual,DM exhaust,CRT Join Date: Jul 2012 Location: Oregon Posts: 5,587 View My Garage	SO your not using warranty...? Its totally not normal to have piston blow apart...and anyway for modding the new ls3 style of the GMMP ported heads for about 1400$ come with hollow stem intakes that l99 engines don't have, sounds like two cases of bad luck as many who do FI don't do cats as that's when they have the chance to screw the pooch from melt down due to the high fuel use ......its fine line with cats to not dump extra fuel and then on the other hand not use too little to run lean... Good Luck to you both and Merry Christmas. Crap Happens.... __________________ 2021 Wild Cherry ZL1 A10, Sunroof, Data, Carbon, Nav, RotoFab Dry CAI, Elite x2, Borla ATK, Driveshaft shop

12-25-2017, 10:44 AM	#4
Olddudesrule Resident nomad Drives: 2014 Summit White 1SS/1LE Join Date: Nov 2015 Location: Gilbert, AZ Posts: 1,765	So what do you think caused it? Engine modded at all. I to have a 2014, and it's been bullet proof so far. Just finishing a LSA install, and am obviously concerned about getting a good, conservative tune on board. __________________ Sold: 2007 Z06 2002 Viper GTS/ACR 2003 Z06 1965 FFR Cobra 2012 Nissan 370Z ADM LSA Stage II, Roto-Fab CAI, Kooks LTH/HFC's, Phastek CC, ported TB, Mishimoto radiator and oil cooler, BC Racing ER Series CO's, JPSS 32mm Black Magic rear bar, JPSS front inserts, R1 Concepts Premier slotted rotors/Goodrich SS lines, Schroth ASM harness, MGW flatstick, Brey-Krause HB, Tuned by NicD, at Cordes Performance Racing.

12-25-2017, 01:07 PM	#5
Bo White Drives: 2015 Summit White 2SS 1LE Join Date: Feb 2012 Location: Vance Alabama Posts: 8,019	What mods? Depends on what went first. The chicken or the egg. Most of the time its hard to tell what failed first. The rod or the piston. __________________ Retired wanna be cylinder head porter 2015 2SS 1LE Clutch reservoir, Vararam DRX, ported TB, TSP 2" headers, MGW shifter Totalled: 2010 1SS Wilkes Performance/Eagle 416 shortblock, TSP custom valvetrain, PRC 260 heads, Edelbrock Pro Flo 102, th400 swap, 8" PTC 5500 stall= 535/435 at the wheels tuned Gen 3 Performance and Dyno 10.97 @ 124 full weight in 3100 DA CamaroFest X

12-25-2017, 01:09 PM	#6
Bo White Drives: 2015 Summit White 2SS 1LE Join Date: Feb 2012 Location: Vance Alabama Posts: 8,019	Most of the time its the piston if its in a million pieces. If the piston is in large pieces then more than likely the rod failed. Not always the case but rule of thumb. __________________ Retired wanna be cylinder head porter 2015 2SS 1LE Clutch reservoir, Vararam DRX, ported TB, TSP 2" headers, MGW shifter Totalled: 2010 1SS Wilkes Performance/Eagle 416 shortblock, TSP custom valvetrain, PRC 260 heads, Edelbrock Pro Flo 102, th400 swap, 8" PTC 5500 stall= 535/435 at the wheels tuned Gen 3 Performance and Dyno 10.97 @ 124 full weight in 3100 DA CamaroFest X

12-25-2017, 01:03 AM	#2
SS PANTHER Drives: 2013 SS Supercharged Convertible Join Date: May 2013 Location: SoCal Posts: 2,714	I’m in the same boat. Cats plugged on my supercharged L99 and damaged the ring lands on 7&8. Going forged internals with new cam and valve train. L99 sucks. Powered rods, hypereutectic pistons, nodular iron crank and lousy lifters and valve train. Hindsight is 20-20. If I would have known where I was going I would have bought the ZL1. Good luck with your rebuild.

12-26-2017, 12:29 AM	#7
Ret Grunt21 Drives: 2014 Camaro SS Join Date: Jun 2017 Location: Albuquerque NM Posts: 12	Well I finished the autopsy so to speak. I’m leaning toward piston failure. Once I pulled the passenger side head, the piston was cracked. So #8 May have been the bystander on this one, and that rod broke too but up at the wristpin end. #7 rod and piston were totally gone. The only mods I have is a CAI and tune. There was a knock coming from the engine for a while and I was thinking that it was a failed DOD lifter. Pulled them all out and they were all good. Plus the number 1 intake pushrod was bent. I bought it used with 29k on it. Plus I found an aFe plastic sticker wedges between the front sway bar bushing and bolt. So the previous owner did something. Also looking at the other cylinders and there still is a crosshatch pattern but the walls appear to have a lot of heat scarring. Not normal. I’m thinking the previous owner put nitrous to it. So basically it was due to fail. __________________ 2014 Camaro SS- Full L99 to LS3 swap with auto trans. Comp 296 HR cam, Comp springs and retainers and Comp chromoly pushrods. CAI, DNA Motorsport Longtube Headers, cat delete, ZL1 mid pipe, Corsa Mufflers, All L99 VVT and DoD deleted. Dyno tuned at Southwest Speed Rio Rancho NM. 400hp and 391 lbs ft of torque.

12-26-2017, 12:33 AM	#8
Ret Grunt21 Drives: 2014 Camaro SS Join Date: Jun 2017 Location: Albuquerque NM Posts: 12	#8 piston and what’s left of #7 piston and half of the rod that I could fish out through the cylinder. Attached Images __________________ 2014 Camaro SS- Full L99 to LS3 swap with auto trans. Comp 296 HR cam, Comp springs and retainers and Comp chromoly pushrods. CAI, DNA Motorsport Longtube Headers, cat delete, ZL1 mid pipe, Corsa Mufflers, All L99 VVT and DoD deleted. Dyno tuned at Southwest Speed Rio Rancho NM. 400hp and 391 lbs ft of torque.

12-26-2017, 07:55 AM	#9
Olddudesrule Resident nomad Drives: 2014 Summit White 1SS/1LE Join Date: Nov 2015 Location: Gilbert, AZ Posts: 1,765	Man, that's some ugly physics right there! Glad you can take it in stride. Opportunity for a great build I guess. __________________ Sold: 2007 Z06 2002 Viper GTS/ACR 2003 Z06 1965 FFR Cobra 2012 Nissan 370Z ADM LSA Stage II, Roto-Fab CAI, Kooks LTH/HFC's, Phastek CC, ported TB, Mishimoto radiator and oil cooler, BC Racing ER Series CO's, JPSS 32mm Black Magic rear bar, JPSS front inserts, R1 Concepts Premier slotted rotors/Goodrich SS lines, Schroth ASM harness, MGW flatstick, Brey-Krause HB, Tuned by NicD, at Cordes Performance Racing.

12-26-2017, 08:24 AM	#10
Bo White Drives: 2015 Summit White 2SS 1LE Join Date: Feb 2012 Location: Vance Alabama Posts: 8,019	Is the block hurt? __________________ Retired wanna be cylinder head porter 2015 2SS 1LE Clutch reservoir, Vararam DRX, ported TB, TSP 2" headers, MGW shifter Totalled: 2010 1SS Wilkes Performance/Eagle 416 shortblock, TSP custom valvetrain, PRC 260 heads, Edelbrock Pro Flo 102, th400 swap, 8" PTC 5500 stall= 535/435 at the wheels tuned Gen 3 Performance and Dyno 10.97 @ 124 full weight in 3100 DA CamaroFest X

12-26-2017, 10:20 AM	#11
NC_SS Drives: 2012 M6 Camaro SS (RIP) Join Date: Nov 2014 Location: Virginia Posts: 1,684	I'm gonna be really surprised if there is no damage to the block That's really nasty, I don't think I've ever heard of a mostly stock L99 popping a piston before I've read about lifters going south but not full piston destruction __________________ Speed engineering 1 7/8 LTs, CAI inc Cold Air Intake, offroad connectors, Solo performance axle back with J pipes, tune, and in need of a driver mod LOL

12-26-2017, 10:22 AM	#12
Reaper85 Drives: 2013 2SS/RS Join Date: Nov 2015 Location: Barrie, Ontario Posts: 598	How long have you had the car? Did it come with any warranty from the dealership you got it from?

12-26-2017, 10:24 AM	#13
NC_SS Drives: 2012 M6 Camaro SS (RIP) Join Date: Nov 2014 Location: Virginia Posts: 1,684	he said it's tuned, so there is no way he will get a warranty claim out of GM lol __________________ Speed engineering 1 7/8 LTs, CAI inc Cold Air Intake, offroad connectors, Solo performance axle back with J pipes, tune, and in need of a driver mod LOL

12-26-2017, 10:39 AM	#14
Ret Grunt21 Drives: 2014 Camaro SS Join Date: Jun 2017 Location: Albuquerque NM Posts: 12	Externally the block is fine, but that doesn’t mean anything. I haven’t pulled the short block yet. When I do pull it I’m not going to tear it down and look. Not going to use this block as it’s not worth the risk after this kind of incedent. Best to get another one and start from scratch on the build. By the way, Bo, I read you Port TB’s. Since mine isn’t in use, I’d like to use your services. __________________ 2014 Camaro SS- Full L99 to LS3 swap with auto trans. Comp 296 HR cam, Comp springs and retainers and Comp chromoly pushrods. CAI, DNA Motorsport Longtube Headers, cat delete, ZL1 mid pipe, Corsa Mufflers, All L99 VVT and DoD deleted. Dyno tuned at Southwest Speed Rio Rancho NM. 400hp and 391 lbs ft of torque.