Hot air stovepipe thing on passenger side...

[dremu]

exhaust manifold. 1974 big block (though my SBC of the same vintage also has it.) What's it do, how's it work?

The tin around the exhaust manifold is, well, falling off something fierce ... I could fix it, or I could just remove all of it (no smog on this old a truck) if it doesn't do much.

Is it only for cold starts, or ...? Never gets below freezing here in California at sea level, so I donno how much good it's doing, blowing hot air into the intake, right?

-- A

 

[sandawgk5]

It takes warm air off of the manifold for the engine. there is a flapper inside the snorkle of the air cleaner that when cold pulls air from the manifold and when warm it pulls it through the snorkle deal. Depending on the year of your vehicle (i.e for smog) you have to have that or it will fail visual.

Ira

 

[prerunner1982]

sandawgk5 beat me to it...

 

[vortec]

mine crumbled off of the k5 about a week after i bought it. never replaced it. and i've been driving my pickup around for most of a decade without one. never had a driveablility or inspection issue because of it. they are getting tight on emissions, here in dfw, but i'm sure it's still much tighter in california.

 

[79k20350]

Being that you are in cali and its pre smog id ditch it.

 

[dremu]

Yup, through '75 is smog exempt, so I don't need it for that ... only question is does it do anything useful, i.e. should I fix/replace the tin, leave the pipe hanging down off the aircleaner (maybe hoseclamp it in place?) or don't even bother with the downpipe?

-- A

 

[Can Can]

I wouldn't worry about it, brother. It's only a necessity in areas where there's a possibility of low temperatures and humidity that together can cause your carb to ice up during a cold start. It *may* help your motor warm up a wee bit faster, but other than that it serves no real purpose in your neck of the woods.

 

[dremu]

I wouldn't worry about it, brother. It's only a necessity in areas where there's a possibility of low temperatures and humidity that together can cause your carb to ice up during a cold start. It *may* help your motor warm up a wee bit faster, but other than that it serves no real purpose in your neck of the woods.

Cool; thanks. One less thing I gotta deal with during the motor swap.

-- A

 

[Avery4jc]

I replaced mine...like $2 for the little slinky pipe thingy at the parts store...and yeah on really cold mornings around here it helps it warm up faster but it's not like you really need it for that.
It will fail the visual inspection around here if you don't have it though.

-Avery