intake manifold

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martingmc86

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have an 86 gmc sierra CA smog complaint but im getting rid of the smog parts dont live in california and im done with the truck running bad......my question is i want to replace the intake manifold but the original intake has an egr i want to replace my old intake with a intake manifold that has no egr .......will the egine run bad with a non egr intake or does it not matter since the intake doesnt have one anymore ive heard people say that trucks run bad when the egr if cap off but this time it will be a whole new intake without egr im running a efi so i dont need an egr
 

Ricko1966

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have an 86 gmc sierra CA smog complaint but im getting rid of the smog parts dont live in california and im done with the truck running bad......my question is i want to replace the intake manifold but the original intake has an egr i want to replace my old intake with a intake manifold that has no egr .......will the egine run bad with a non egr intake or does it not matter since the intake doesnt have one anymore ive heard people say that trucks run bad when the egr if cap off but this time it will be a whole new intake without egr im running a efi so i dont need an egr
It won't matter one way or the other. And having an egr valve on your old manifold won't matter either,you can leave the valve in place without it hooked up,and it still won't matter.Only way it would matter is if the EGR valve is stuck open, with no vacuum it should be closed.Your intake manifold isn't what's making your truck run bad. But if you want to change it,go ahead be aware your heads are most likely new style meaning if you run an earlier intake you will need to egg out the center 2 holes on each side and use tapered washers,rocker balls something on the center bolts. Or be sure to order the correct manifold for the newer heads
 
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martingmc86

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It won't matter one way or the other. And having an egr valve on your old manifold won't matter,you can leave the valve in place without it hooked up,and it still won't matter.Only way it would matter is if the EGR valve is stuck open wuth no vacuum it should be closed.Your intake manifold isn't what's making your truck run bad. But if you want to change it,go ahead be aware your heads are most likely new style meaning if you run an earlier intake you will need to egg out the center 2 holes on each side and use tapered washers,rocker balls something on the center bolts. Or be sure to order the correct manifold for the newer heads
thank you good to know is there a way to know if the egr is staying open
 

Ricko1966

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thank you good to know is there a way to know if the egr is staying open
Engine idling apply vacuum to the egr valve you should here a big difference in idle when the vacuum pulls the egr valve open.if it doesn't change it is either stuck open( very doubtful) or doesn't work,period. You could pull it,apply vacuum and verify it moves if you need to. You can just put on a block off plate. Have you run compression,and checked vacuum readings on this engine?
 
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martingmc86

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Engine idling apply vacuum to the egr valve you should here a big difference in idle when the vacuum pulls the egr valve open.if it doesn't change it is either stuck open( very doubtful) or doesn't work,period. You could pull it,apply vacuum and verify if you need to. You can just put on a block off plate. Have run compression,and checked vacuum readings on this engine?
i have a block plate I'll be putting one on also since my efi been running pretty bad......also msd recommends I get rid of my original distributor Hei controlled by my trucks computer and install a Hei without my computer i saw one online msd Hei Street fire do you happen to have knowledge on this thank you
 

Ricko1966

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i have a block plate I'll be putting one on also since my efi been running pretty bad......also msd recommends I get rid of my original distributor Hei controlled by my trucks computer and install a Hei without my computer i saw one online msd Hei Street fire do you happen to have knowledge on this thank you
What does atomic EFI recommend for a distributor? If they recommend a generic 49 states HEI than a street fire would probably be a good one for you. Not my 1st choice,but that's because I want something I can for sure tailor with factory GM parts.
 
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martingmc86

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What does atomic EFI recommend for a distributor? If they recommend a generic 49 states HEI than a street fire would probably be a good one for you. Not my 1st choice but that's because I want something I can for sure tailor with factory GM parts.
what would you recommend ill take any recommendation
 

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what would you recommend ill take any recommendation
Use what atomic says. If they say generic HEI,street fire would be a good choice for you. You aren't going to play with eccentrics,weights,springs,advance cannister like me. That's why they wouldn't be a number one choice for me. If I wasn't going to play with it a streetfire would be fine with me.
 
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martingmc86

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v8 5.0
Use what atomic says. If they say generic HEI street fire would be a good choice fir you. You aren't going g to play with eccentrics,weights,springs,advance cannister like me. That's why they wouldn't be a number one choice for me. If I wasn't going to say with it a streetfire would be fine with me.
sounds like a plan I'm aware ill have a check engine light but I'll probably disconnect the light bulb what about the knock sensor will be there a issue since my knock sensor won't be getting a reading?? will this affect performance or damage the engine
 

Ricko1966

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sounds like a plan I'm aware ill have a check engine light but I'll probably disconnect the light bulb what about the knock sensor will be there a issue since my knock sensor won't be getting a reading?? will this affect performance or damage the engine
Nope it will all be fine
 

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