Emissions issue

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SirRobyn0

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@CRM Thanks for that I just learned something new. Federal emissions non-Cat equipped K2500 were available up until 86. Looks like there is an RPO code that would determine for sure if it came factory with or without a cat. The notes say most K2500's came catalytic converter equipped with a particular RPO code that I didn't think to write done. I'm sorry I thought those days were over by about 1980... I was wrong. Interestingly enough K20's seem to have all had cat converters by then.
 

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If it’s a California truck, the smog is unique
 

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WFO

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@CRM Thanks for that I just learned something new. Federal emissions non-Cat equipped K2500 were available up until 86. Looks like there is an RPO code that would determine for sure if it came factory with or without a cat. The notes say most K2500's came catalytic converter equipped with a particular RPO code that I didn't think to write done. I'm sorry I thought those days were over by about 1980... I was wrong. Interestingly enough K20's seem to have all had cat converters by then.
My 86 K20 never had cats, and has the large fueling hole for leaded gas.
It's C6P optioned.
 

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Good to know. I really had no idea non-cat was an option so late into the 80's.
It had to be a 20 or 30 for no cats if I recall. Mine is an 81 C20, only has the smog pump. I have been tempted to add a cat just to cut down on the exhaust smells.
 

SirRobyn0

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It had to be a 20 or 30 for no cats if I recall. Mine is an 81 C20, only has the smog pump. I have been tempted to add a cat just to cut down on the exhaust smells.
I was tempted to mention that earlier. Other than the cost of the cat or cats there is no reason a guy can't add them if he wants too. I'm in that camp too. I'd add them if my truck was cat-less even if it came from the factory that way. I've just become way to sensitive to exhaust anymore.
 

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I was tempted to mention that earlier. Other than the cost of the cat or cats there is no reason a guy can't add them if he wants too. I'm in that camp too. I'd add them if my truck was cat-less even if it came from the factory that way. I've just become way to sensitive to exhaust anymore.
I believe the engine RPO for a HD emissions engine or a emissions bypass or something like that was. C6p was definitely the route if you went gvw for it I guess.
the HD emissions engine will make more torque but less HP and it will require 91 when not using leaded gas
 

fast 99

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Here's one for all of you. My 85 K20 doesn't have a cat and doubt it ever did [no fuel fill restrictors]. However, my other truck an 81 K20 has a cat and always did, with restrictors. Both are 350, auto, without floater rear ends. So, neither was high GVW. Bought the 81 new.

Haven't put a cat on the 85 because I use it to burn end of season boat and AV gas. It likes the AV gas.
 

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Here's one for all of you. My 85 K20 doesn't have a cat and doubt it ever did [no fuel fill restrictors]. However, my other truck an 81 K20 has a cat and always did, with restrictors. Both are 350, auto, without floater rear ends. So, neither was high GVW. Bought the 81 new.

Haven't put a cat on the 85 because I use it to burn end of season boat and AV gas. It likes the AV gas.
AV gas is great stuff! I used to run a 25% blend in my trucks and man did they run well like that. That was in '98-'99 and it was $1.07, which was expensive. I'd hate to see how much it is now.
 

fast 99

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AV gas is great stuff! I used to run a 25% blend in my trucks and man did they run well like that. That was in '98-'99 and it was $1.07, which was expensive. I'd hate to see how much it is now.
Early this spring was about $5.50, hasn't gone up too much. Just checked price online, 6.43 at a local airport.

Pump gas here today is close to $5. Too bad we have to run the 91-e free crap. Seems every year the octane drops another point. Use to be 93 or 94.
 

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Does your state even check emissions on older vehicles? You might check. many states have a provision for vehicles over a certain age being exempt. If that is the case less is best when it comes to emissions equipment. It's often easier to take a lot of it off and remove 40 year old rubber lines to eliminate vaccum leaks and such. Just food for thought.
this exactly. If you don't have to pass emissions, then less is more. Yes, like SirRobyn says the stuff that comes out of tailpipes is technically bad for your lungs and brain at huge concentrations, but if you're not in the habit of running the truck in the garage for long periods of time or making out with your tailpipe, you and everyone around you will be A-OK. You probably won't notice much of an INCREASE in power or fuel economy (though technically there will be a slight gain to both), but what can HURT both of those is vacuum leaks, drag from belts and worn bearings, etc. If the stuff is already off and you have no legal requirement to get it working again, then buying the missing parts only costs more money, and installing them only causes more chances for headaches. When brand new and it was working fine there would be no good reason to remove it, but now that these trucks are ~40 years old the more crap going on under the hood is just more things that can potentially fail and make your truck not run right or even get you stranded worst case scenario. Personally under MY hood, the only things I need are an engine, fuel system, simple cooling system, and a simple charging system. All that other crap can p!ss off as far as I'm concerned. Easier and cheaper to own and maintain, less chance for breakdown, and literally zero downside unless you live in an area that forces the issue and you're the type that enjoys following silly rules...
 
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SirRobyn0

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@CRM & @RecklessWOT & everyone else. Wa St ended all emissions testing Jan 1 2020. However I've heard rumors that a much more stringent program could be coming anytime. Expected to be similar to Oregon's system. If that were to happen we'd be testing everything 1975 and newer with no wavers. But would Pasco be apart of it, or would it just the Puget sound and Spokane? Who knows, will it ever happen? who knows, I'm starting to think not, but who knows? I'd just say if a guy around here decides to strip it, hang on to the parts because it'll be hard to find later on if it becomes required.
 

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