Generation III Internal Engine 1997-2006 LS1 | LS6
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Breakup at about 4500

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Old 05-24-2021, 07:30 PM
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Default Breakup at about 4500

So I’m new to these engines and mainly drag race my truck but we had just swapped in an 01 Silverado motor and put the summit stage 4 cam in with new springs, pushrods, injectors, and a holley terminator x computer. First couple events it ran great with only some minor tuning adjustments and then out of nowhere it started to slow down and break up to the point where now under wot I can’t even make it past 4500 without letting it breaking up and dying until I lift off the pedal. Ran through checking wires, swapped o2, checked plugs, valve springs, and fuel filters. I have some data logs ill find out how to throw in here but any advice would be appreciated before I send it out to be gone through
Old 05-24-2021, 08:07 PM
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one pass maxed out the 36 lb injector duty cycle but both act the exact same down track
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Old 05-24-2021, 08:19 PM
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Coils or valve springs?
Old 05-24-2021, 09:08 PM
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TFS-2500286P These are the springs that were installed. Just checked to make sure the rockets were tight today it all seemed fine. But the coils are still from the motor when I got it. I’ll have to take my daily’s coils for a test

Old 05-25-2021, 11:28 AM
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What is your compression?
Old 05-25-2021, 06:49 PM
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Originally Posted by Darth_V8r
What is your compression?

Old 05-25-2021, 11:25 PM
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What's your fuel pressure when it noses over/breaks up??
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Old 05-26-2021, 07:34 AM
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Originally Posted by Adamlint0
Thanks. I should have asked a better question, although I'm glad you've checked compression already. Have you tried shooting a squirt of oil into the lower reading cylinders to see if they improve? if that works, it typically indicates ring wear.

The question I was actually asking is what is your static compression ratio?
Old 05-26-2021, 12:42 PM
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Originally Posted by Darth_V8r
What is your compression?
mall cylinders between 145-160 and one up at 180
Old 05-26-2021, 12:43 PM
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Originally Posted by CattleAc
What's your fuel pressure when it noses over/breaks up??
Steady 62-63 psi all the time
Old 05-06-2022, 07:11 PM
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Originally Posted by Adamlint0
Steady 62-63 psi all the time
Did you ever get this figured out? Same issue with my LS3.
Old 05-06-2022, 07:15 PM
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Default Fixed issue

Originally Posted by plentiswalter
Did you ever get this figured out? Same issue with my LS3.
yes I actually did. It ended up being some pretty clogged injectors. Even though the fuel system was pretty much all new. My injectors were maxing out the duty cycle but afr was dead lean. Confused me for a while
Old 05-06-2022, 10:24 PM
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Originally Posted by Adamlint0
yes I actually did. It ended up being some pretty clogged injectors. Even though the fuel system was pretty much all new. My injectors were maxing out the duty cycle but afr was dead lean. Confused me for a while
Wow! Thanks for the reply man! Glad you got it figured out. It’s funny that is actually where I was leaning because I have checked everything else on the car. Just get new ones? Or clean the oldies out? Thanks again man.
Old 05-06-2022, 10:49 PM
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Default Injector issue

Originally Posted by plentiswalter
Wow! Thanks for the reply man! Glad you got it figured out. It’s funny that is actually where I was leaning because I have checked everything else on the car. Just get new ones? Or clean the oldies out? Thanks again man.
so one of the guys at my work knew I guy with and injector tester and the tools to clean them. He ended up just swapping out my baskets because it looked almost like they had sand in them it was weird. But they tested fine after and have worked ever sense so it’s worth a try to check them. Hope this helps out
Old 05-06-2022, 10:58 PM
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You’re the man!!! Really appreciate it
Old 05-07-2022, 02:59 PM
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Exclamation Example............


Obvious issue with performance.

Change the filter baskets. No other corrections made.



Quick Reply: Breakup at about 4500



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