81 C10 383 stroker stinks

chipmaker

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My truck stinks. Its tuned, headers and exhaust out back. It stinks driving, idling and moving into and out of garage. It smells crazy rich, but isnt running rich. The smell goes from garage into house. I hate it, wife really hates it. What can I do? Will cats kill the smell? It cant be leaned out. Classic car insurance wont let me store it outside. Thanks for any help...
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Raider L

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@chipmaker,

Give me some more info on your engine and more info on your exhaust other than headers. Do you have any catalytic converters on your truck? If you do, they are notorious for smelling bad. If you've got catalytic converters on your truck you can remove them and get Flowmaster cat's that don't have anything in them other than some screening. They look like a reagular cat, but they are made for racing. They are not that expensive, hook up in the same place with no mods and have no smell.
 

Raider L

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@chipmaker,

Oh, I went back to the site titles and saw where your thread is a 383. Okay. The only thing I can think of for the stink is the cat. conv.. Have you checked to see if there's a dead rat hung up in the underside?
 

chipmaker

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I am running hedman headers to Turbo style exhaust. No cats. Its a old truck smell, not dead animals. LOL. Smells rich but isnt.
 

MelbGMC

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My new 350 with alloy heads, cam and edelbrock carb does exactly the same thing, smells rich as f$%k but isn't running rich.
I'm about to install a new exhaust and see if that helps at all.
And I'm getting that black sooty looking crap coming out of the exhaust as well when its cold.
 

BillK

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If it stinks then something is wrong. You say its not rich but it probably is. Cars back in the 60's 70's did not run as clean as modern ones but they did not stink. They always ran a little rich when cold because of the choke but once the choke opens they can be very "clean" running.

You need to take it to somebody that knows how to tune it and has the equipment to monitor the exhaust while doing the tuning.

What ignition system ? Does it have vacuum advance ?
 

yevgenievich

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Cam profile will cause exhaust to stink while running correctly as well
 

Ellie Niner

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My new 350 with alloy heads, cam and edelbrock carb does exactly the same thing, smells rich as f$%k but isn't running rich.
I'm about to install a new exhaust and see if that helps at all.
And I'm getting that black sooty looking crap coming out of the exhaust as well when its cold.
If you're getting soot, you are definitely running too rich. Whether that's too much choke when it's cold, float level, stuck or wrong power valve settings... something ain't quite right.
 

SquareRoot

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I'm with Bill.

Why do you guys say its stinks, smells like fuel and insist it's not running rich? How do you know that? Do you have an O2 sensor to give you that data? Chances are it's running rich despite your insistence that it isn't.

With todays fuel you CANNOT read the plugs and get any useful information on the AF ratio. Sorry. I went thru this learning curve when I added my Edelbrock EFI recently.
 

Grumpy

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Spend a couple bucks and get a basic O2 sensor kit and verify it absolutely. You don't need to keep the gauge in the truck, just use it to get dialed in - you can always thread a plug into the exhaust **** later.
I suggest you start from scratch and verify the basics, starting with a good air filter, then fuel pressure (too high can be a serious problem) then move to float level and idle mixture. Ensure you have no plugged vents.
It all takes time, but everyone always skips the basics.
 

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Spend a couple bucks and get a basic O2 sensor kit and verify it absolutely. You don't need to keep the gauge in the truck, just use it to get dialed in - you can always thread a plug into the exhaust **** later.
I suggest you start from scratch and verify the basics, starting with a good air filter, then fuel pressure (too high can be a serious problem) then move to float level and idle mixture. Ensure you have no plugged vents.
It all takes time, but everyone always skips the basics.
Hahahahahahha the forum rules censored the word "****" because it thought it was naughty...
"b.u.n.g"
 

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