What is this ?

Exhaust

  1. 72RR440

    72RR440 Member

    Messages:
    22
    Likes Received:
    Joined:
    Mar 3, 2018
    Location:
    SW Florida
    It's on the passenger side exhaust manifold. Looks like some kind of open/close valve. 20180310_093707.jpg
     
  2. droptop

    droptop Well-Known Member

    Messages:
    3,433
    Likes Received:
    Joined:
    Sep 11, 2008
    Location:
    Southern Indiana
    Heat riser. Closed when engine is cold to force hot exhaust through the intake manifold under the carburetor to run better and warm up quicker on those cold mornings. Most likely not needed in SW Florida. LOL.
     
    Ranger and Coyote like this.
  3. Terry Hauck

    Terry Hauck Choadicus

    Messages:
    70
    Likes Received:
    Joined:
    Sep 6, 2017
    Location:
    Mojave Desert
    I see your engine block is turquoise. What model and year is your car?
     
  4. 72RR440

    72RR440 Member

    Messages:
    22
    Likes Received:
    Joined:
    Mar 3, 2018
    Location:
    SW Florida
    72 GTX RR 440 4spd 4bbl
     
  5. Terry Hauck

    Terry Hauck Choadicus

    Messages:
    70
    Likes Received:
    Joined:
    Sep 6, 2017
    Location:
    Mojave Desert
    NICE!!
     
  6. Ranger

    Ranger Well-Known Member

    Messages:
    1,238
    Likes Received:
    Joined:
    Dec 25, 2014
    Location:
    Woodstock ll
    I wired mine full open and rendered it inop on my first Road Runner back in '69. Thankfully it had been removed in my current Road Runner before I purchased it. It is pretty much an early (and poor) attempt at emission control.
     
  7. Big John

    Big John Sit back, relax Don't bitch about the cigar smoke

    Messages:
    5,005
    Likes Received:
    Joined:
    Sep 8, 2008
    It has zero to do with emissions.

    It's function is to heat the underside of the intake manifold for better running when the car is cold.
     
  8. Ranger

    Ranger Well-Known Member

    Messages:
    1,238
    Likes Received:
    Joined:
    Dec 25, 2014
    Location:
    Woodstock ll
    And by "better running when the car is cold", emissions are reduced by getting it up to operating temp quicker. Right?
     
  9. Big John

    Big John Sit back, relax Don't bitch about the cigar smoke

    Messages:
    5,005
    Likes Received:
    Joined:
    Sep 8, 2008
    Probably, but it's not part of the emissions package and something that was used for years before emission standards were even thought of.
     
  10. Russ69Runner

    Russ69Runner Well-Known Member

    Messages:
    1,448
    Likes Received:
    Joined:
    Aug 4, 2016
    Location:
    Lake Wales Fl.
    It dose get pretty cold here in the winter. Not as cold as up north but we do get into freezing here. Have seen it 27 degree here and it was below 32 for two day's. Being in central Fl. So that being said will rebuild my heat riser for those cold morning's. Getting older suck's will need a heater in the car for warming me up. LOL.
     
  11. dmartin

    dmartin Well-Known Member

    Messages:
    483
    Likes Received:
    Joined:
    Aug 30, 2013
    Location:
    Georgia
    I here ya Russ my heater works good when not moving I need to replace the fresh air vent gaskets or like I do now use rags over the vents
     
  12. Russ69Runner

    Russ69Runner Well-Known Member

    Messages:
    1,448
    Likes Received:
    Joined:
    Aug 4, 2016
    Location:
    Lake Wales Fl.
    Yep fixed mine welded cover's over them. Figure the vent window's will give me enough fresh air. With the added vintage air and heat should be fine. Found one heat riser repair kit for the 383. Don't forget that you can find something's not listed for Roadrunners but the same thing's where used on pick up truck's and Van's. That is how I found the striker plate for the door latch. Mine had a grove worn in it both sides. They look grate brand new always dose's.
     
    Last edited: Mar 27, 2018
  13. bjersauto

    bjersauto Well-Known Member

    Messages:
    60
    Likes Received:
    Joined:
    Mar 14, 2017
    Location:
    usa
    it is smog related it’s the heat riser for cleaner faster warm ups in California if it is missing the vec fails smog. you would mark as modified.
     
  14. RRDon

    RRDon Member

    Messages:
    13
    Likes Received:
    Joined:
    Feb 9, 2017
    Location:
    Hurricane, UT
    HEAT RISER VALVE = TOTAL CRAP!!! These damn things always wind up corroding and getting stuck, usually in the closed position causing burnt valves or worse! They also restrict exhaust flow (even when open) which reduces horsepower. And I'm assuming that since you are a Mopar fan you like horsepower ;))
    This is the FIRST thing I remove from any car that has one. It's not too hard to remove it, just drop your head pipe and remove the exhaust manifold for access. I removed it from each of the 4 road Runners I have owned, even back in 1970 on my brand new RR. Even back then everybody knew to get rid of those damn things before they damage your engine.
    For maximum exhaust flow efficiency out of a stock manifold, it's best to remove the whole thing including the shaft the flapper valve rides on. Then you can plug the holes (from the outside) with a short oversized bolt or have a welder fill it and and grind flat. Lots of options how to do this just make sure you get rid of that damn valve.
    Note: When you remove the exhaust manifold take a look inside it. I'll bet it has carbon build up from restricted flow.
    Good time to clean it out.
     
    Ranger likes this.
  15. Terry Hauck

    Terry Hauck Choadicus

    Messages:
    70
    Likes Received:
    Joined:
    Sep 6, 2017
    Location:
    Mojave Desert
    Get some good headers. That will eliminate it and it will sound and look nicer. That's what I did anyway.
     

Share This Page