C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

85' Proper EGR Delete

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Old Today | 12:24 AM
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Default 85' Proper EGR Delete

Is there a proper way to delete EGR system? Previous owner has the block off plate installed behind the intake manifold I can see it.. but there is leftover lines all over the engine bay.

Will take pictures and upload tomorrow.

Is there a write up , really detailed youtube video? Or the like?
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Old Today | 11:19 AM
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Originally Posted by ThomasVFree
Is there a proper way to delete EGR system? Previous owner has the block off plate installed behind the intake manifold I can see it.. but there is leftover lines all over the engine bay.

Will take pictures and upload tomorrow.

Is there a write up , really detailed youtube video? Or the like?
Personally, in my opinion, unless you're making radical changes to your stock engine and factory ECM...you would be better off sourcing a correct EGR valve and installing it, along with replacing any vacuum lines that have deteriorated or are missing! Your stock computer expects that EGR valve to be there and sends commands to it accordingly...there is really no real-world performance gain to be had by deleting it on a stock setup...and actually you may experience more negative effects! Now the A.I.R/smog pump system on the hand is a different story, I know you didn't mention it, but if you're looking to "clean-up" the engine bay and possibly do any exhaust upgrades or the catalytic converter has been removed or needs attention...you may want to do some research on removing this system. But, stock engine, stock computer....put a new EGR valve back on it...just my 2 cents worth👍
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Old Today | 12:34 PM
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Originally Posted by '78CorvetteS.A.
Personally, in my opinion, unless you're making radical changes to your stock engine and factory ECM...you would be better off sourcing a correct EGR valve and installing it, along with replacing any vacuum lines that have deteriorated or are missing! Your stock computer expects that EGR valve to be there and sends commands to it accordingly...there is really no real-world performance gain to be had by deleting it on a stock setup...and actually you may experience more negative effects! Now the A.I.R/smog pump system on the hand is a different story, I know you didn't mention it, but if you're looking to "clean-up" the engine bay and possibly do any exhaust upgrades or the catalytic converter has been removed or needs attention...you may want to do some research on removing this system. But, stock engine, stock computer....put a new EGR valve back on it...just my 2 cents worth👍
While I do agree the previous owner chopped off the cat and has a horrible exhaust setup underneath along with already disconnected lines and a EGR plate installed. Might be easier to just delete the rest for now as my car does run just fine but need to get the ECM to recognize it’s not a leak (assuming my vac leak is coming from those disconnected lines until I smoke test.)

I will highly consider that route if the EGR delete bypass does not provide a solid fix and or my leaks are coming from it. Not sure yet. Thank you for your response!!
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