Please look over my emissions “delete”

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mtbadbob

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It most definitely running at 4 grand or at least around there. Unless again I almost close the choke.
This may be easier over the phone. Give me a call- 406-439-4276...Bob
 

nolanswiger

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This may be easier over the phone. Give me a call- 406-439-4276...Bob
Hey man I now you mean well and want to help but I don’t want to share information like this, I’m going to ask someone I know if they could help but all the help you guys have given is much appreciated.
 

mtbadbob

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Hey man I now you mean well and want to help but I don’t want to share information like this, I’m going to ask someone I know if they could help but all the help you guys have given is much appreciated.
Ok, it just seems to me like there is either something inside the carb holding the throttle plate open, or the cable isn't allowing it to return to the idle position. It shouldn't be running that high of rpms without the throttle being open somehow. Good luck!
 

nolanswiger

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Ok, it just seems to me like there is either something inside the carb holding the throttle plate open, or the cable isn't allowing it to return to the idle position. It shouldn't be running that high of rpms without the throttle being open somehow. Good luck!
Again man thank you it’s first time I’ve dived this deep into something, have a good rest of your day.
 

JBswth

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Did you check vacuum to the distributor as I told you on post 13 of your 1st post? What are the results? I'd want my egr hooked up especially,on a 305 to prevent detonation. EGR goes away on its own,by design when you givebit throttle,it also decreases combustion temperature and increases mpg, so no reason to delete it. But good reasons to keep it.How are you dealing with the cannister? You have to have some way for the tankbto vent. Using the cannister is the best way. Venting to atmosphere allows your fuel to evaporate into space,without you getting to burn it,it also allows water into the gas tank,due to condensation. Rusts the tank,and fuel lines. Now go pull the vacuum hose off of the distributor at the distributor, and plug it. Did your idle come down?
I agree about the canister and about possible vacuum leaks, but I hate EGR. It considerably reduces torque at light to part throttle cruise, forcing you to use more throttle than you otherwise would use when you encounter a grade or want to increase your speed some. Also, in about 1980, GM started using back-pressure modulated EGR, which does NOT completely close when you give it heavy throttle.
 
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Ricko1966

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I agree about the canister and about possible vacuum leaks, but I hate EGR. It considerably reduces torque at light to part throttle cruise, forcing you to use more throttle than you otherwise would use when you encounter a grade or want to increase your speed some. Also, in about 1980, GM started using back-pressure modulated EGR, which does NOT completely close when you give it heavy throttle.
I really don't want to debate egr., run it,don't run it IDC . It is there to reduce combustion temperature,allowing more timing,without detonation,it also reduces NOX, the additional timing,offsets the slower burn,from the egr diluted mixture. The additional throttle needed to pull a hill is to give it the fuel the egr is with holding that fuel you wete going to already be burning,with out the egr to offset it,and weren't going to climb the hill with or without egr without more throttle. The additional throttle angle reduces pumping losses,the engine turns over easier with the throttle open,as long as additional fuel isn't being consumed the higher thrittle angle is more efficient and increases mpg,EGR also increases mpg by partially filling the cylinder with a mixture other than fresh fuel and air,(its a glass half full thing)the increased timing increases mpg. Many engines will detonate badly if you disable egr. Those are things anyone can google and make up their own mind about.There's plenty of science and engineering to back it up.EGR was added as primitive engine management to reduce emissions but also to help meet CAFE (mpg)and octane demands.Manufacturers weren't just told cut emissions,they were told cut emissions,and bring up fuel economy.My own theory is a lot of the post EGR heads that are cracked, that everyone labels as bad castings,are caused by disabled EGR the extra heat and preignition I believe contributes to cracking the heads. And FWIW for years, maybe decades I hated EGR,I disabled EGR,and as I learned more about it and all the ways it works that we don't see and most don't know,I changed my opinion. If I buy something with disabled EGR I enable it tune it and go happily on with some extra mpgs and the ability to run cheap fuel.
 
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JBswth

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I really don't want to debate egr., run it,don't run it IDC . It is there to reduce combustion temperature,allowing more timing,without detonation,it also reduces NOX, the additional timing,offsets the slower burn,from the egr diluted mixture. The additional throttle needed to pull a hill is to give it the fuel the egr is with holding that fuel you wete going to already be burning,with out the egr to offset it,and weren't going to climb the hill with or without egr without more throttle. The additional throttle angle reduces pumping losses,the engine turns over easier with the throttle open,as long as additional fuel isn't being consumed the higher thrittle angle is more efficient and increases mpg,EGR also increases mpg by partially filling the cylinder with a mixture other than fresh fuel and air,(its a glass half full thing)the increased timing increases mpg. Many engines will detonate badly if you disable egr. Those are things anyone can google and make up their own mind about.There's plenty of science and engineering to back it up.EGR was added as primitive engine management to reduce emissions but also to help meet CAFE (mpg)and octane demands.Manufacturers weren't just told cut emissions,they were told cut emissions,and bring up fuel economy.My own theory is a lot of the post EGR heads that are cracked, that everyone labels as bad castings,are caused by disabled EGR the extra heat and preignition I believe contributes to cracking the heads. And FWIW for years, maybe decades I hated EGR,I disabled EGR,and as I learned more about it and all the ways it works that we don't see and most don't know,I changed my opinion. If I buy something with disabled EGR I enable it tune it and go happily on with some extra mpgs and the ability to run cheap fuel
 

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