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Discussion Starter #1
Guys I did a 180 mph pull the other day. Immediately after when I went WOT the car would misfire and bog down. I changed the plugs but it still does the same thing. The attached picture is a picture of one of the plugs. When this happened is it possible the pieces damaged the injector? Thanks in advance.
 

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Injectors in LS engines are not in the combustion chamber.
 

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Discussion Starter #3 (Edited)
Ok dang I didn’t even think about that. But something is causing it to bog down really bad at WOT. I’m not even getting a misfire CEL. Doesn’t do it at 3/4 throttle though.
 

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Did you throw a scope down into the cylinder(s) with the blown plugs?
 

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Get a borescope and look in the cylinder.

Maybe a hole in a piston.
 
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any HPT logs?
 

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Gap and over enrichment? Logs will help.
 

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Check the oil for contamination. These cars can run pretty well even on 6 or 7 cylinders.

The broken plug is suggestive of significant detonation- which hyperuetectic pistons don't like. A borescope on that cylinder will probably reveal damage.

Sent from my SM-G965U using Tapatalk
 

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I'd like to see a map reading and log with idle , tip in-wot log .

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Sounds like a stuck open valve. It is possible that a retainer cracked, causing a valve to drop and cause damage to the plug. I suggest removing the valve covers to inspects all valve springs and retainers.
 

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Check the oil for contamination. These cars can run pretty well even on 6 or 7 cylinders.

The broken plug is suggestive of significant detonation- which hyperuetectic pistons don't like. A borescope on that cylinder will probably reveal damage.

Sent from my SM-G965U using Tapatalk
THIS ^^^^^^^^

Looks like the engine detonated badly......a long pull like that probably saw very high IAT's making the engine more prone to detonate.

Boroscope to check the piston is bonus which has been suggested already and a leak down is really key. In the event its not good (the leak down test) you will be able to track down whether its leaking badly into the crankcase or through an intake or exhaust valve. A compression test will only show your potentially down on cranking PSI but it wont help you find the root cause of the leak.

Good luck.....keep us posted on what you ultimately find

-Tony
 
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