84 K20 with 454 back to stock configuration

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Desertguy

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Hello. New guy here. I just got an 84 K20 4x4 4speed manual that originally had a 350. I bought it with a carbuerated 454. I need to get it Cali smog legal. I've got a couple ways to do this. I can hopefully either make the 454 back to factory standards and have all the original smog equipment, or I can put a 350 in it with all the smog stuff too.

Was the 454 an option in the 84 K20? Did the 1984 454 have TBI or some sort of fuel Injection in 84?

Did the 84 K20 have carb or fuel injection?

if I need to convert this back to fuel injection, I'll have more questions.

I picked this up for $500 with a super straight body in pretty good condition. It's the yellowish tan color. Single cab long bed. Not being able to smog it in Cali makes it a bit of a problem. Thanks for your help!
 

yevgenievich

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Would be carbed for 84 either 350 or 454. Finding smog parts might be the hard part. Should be without cats for 84
 

Desertguy

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Interesting. The previous owner tried to get it smogged at the referee station and they told him it needed fuel injection to be legal. It's originally an Arizona car. I guess i just get it running and see if it'll pass
 

C10MixMaster

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Interesting. The previous owner tried to get it smogged at the referee station and they told him it needed fuel injection to be legal. It's originally an Arizona car. I guess i just get it running and see if it'll pass

If you can find an unmolested 84 350 you would not have to deal with a referee station anymore. California allows swaps you might have to jump through some hoops though. A legal swap would be any engine of the same class ,Heavy Duty in this case, from the same year or newer. do you know what the 454 came from, that will make a difference. Fuel injection started in 1987 so unless the donor engine is 87 or newer it should not have to have fuel injection. You might want to start by visiting a referee station since they get the final say on any swaps.
 

Shorty81

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Welcome, damn nice Chevrolet !!!
 

Craig 85

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I have an '85 K30. It was manufactured 11/84 before the 1/1/85 federal emissions changes. Due to that fact, I have OEM '84 emissions in my truck. As far as I know, 454's were only available in 3/4 ton 2WD trucks and Suburbans. You could get a 454 in 2 or 4WD 1 tons.

Before you contact the referee, I would find out if your truck was a California or Federal emissions truck. Another member has an '85 dually with Federal emissions. We were able to determine the Federal trucks did not have an EGR, and California's do. Your biggest hurdle will be if the referee will let the 454 stay. Explaining that they were available in 2WD drive C20's and C/K30 trucks maybe they will allow it. California used to require the engine block replacements to be the same age or newer than what it's replacing. I have a '90 454 GM replacement block in mine. It means I could switch to 1990 emissions and any exempted parts related to it.

When I bought my truck, it did not have the emissions installed, but I had them. I replaced almost all the the related parts with new or rebuilt items and it passed smog no problem. Your truck looks pretty complete, but if you don't know which emissions came in your truck, you will have to go by the original California standards.
 

Desertguy

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Thanks for all the helpful info. The 454 came out of a motorhome. Not sure of year or anything. I guess I'll start with looking at it and see what smog equip it has and if it looks like anything was removed. Shouldn't be too hard to get going. Last ran 5 years ago and it sat since. The referee thing is kind of a pain, we live way out in the desert and it's about 1.5 hours to the next big city, but ooh well. Hopefully tow it there and see what they say I need to do, then tow it back when it's done. Look forward to getting this thing on the road again.

How do I tell if it's a federal or CA model? Looks like the sticker shows an EGR.

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C10MixMaster

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Thanks for all the helpful info. The 454 came out of a motorhome. Not sure of year or anything. I guess I'll start with looking at it and see what smog equip it has and if it looks like anything was removed. Shouldn't be too hard to get going. Last ran 5 years ago and it sat since. The referee thing is kind of a pain, we live way out in the desert and it's about 1.5 hours to the next big city, but ooh well. Hopefully tow it there and see what they say I need to do, then tow it back when it's done. Look forward to getting this thing on the road again.

How do I tell if it's a federal or CA model? Looks like the sticker shows an EGR.

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the part that would say California is smudged out but it looks like federal to me? but it does shows all the equipment you need for the original 5.7. if the rpo sticker is still in the glove box it will show a code for California compliant also. Motor homes got carbs past 87 that might be the problem with the referee wanting fuel injection. motor home might also be a different motor class.
 

Desertguy

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No code on the RPO, so looks like it's a federal, I guess. That's a good sign. Yeah, I'll have to let it play out and see what the refs say, and go from there. Meanwhile I'll be browsing around here learning more about this truck.

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Craig 85

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I would agree it's federal, based on the RPO codes and it looks like it says "US" on the bottom line of the emissions tag. Mine has California emissions right on it and RPO code "YF5". I've had three 3/4 ton Squarebody trucks and a C20 Suburban all had a GVW of 8600 LBS which qualified all of them for heavy duty emissions.

The sticker on the core support calls out the truck as light duty emissions and the truck being a catalyst (EGR too). The tire size of LT215/85R16 is a flag too. All of mine were 235's. I have a sales brochure for my '85 and I looked at the chart within and guess what, I found they made a light duty K20 truck. It only has a GVW of 6600 LBS. The 8600 GVW would have RPO C6P.

Based on this, I don't think the referee would allow the 454 as that was a heavy duty emissions motor. You don't have to take your vehicle to the referee initially, you can call them. When I sold my last truck a couple of years ago had some issues pop up. I spoke to a referee based out of a junior college in the San Diego area. I don't know if this number is still good, but it's worth a try. His name was Dan (619) 663-2074.

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Desertguy

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Ooh wow. Thanks for doing that research for me. Well, that's not looking good so far. Lol. We'll see what the referee says and I'll go from there.
 

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