Exactly.
Heat Riser?
Team Owner
Joined: Jul 2006
Posts: 22,206
Likes: 4,191
From: Kannapolis NC
Mine is cut out and the choke works fine. The hot air line coming up through the exhaust manifold feeds heat to the choke to loosen the spring so it pulls off. The heat riser heats the intake manifold under the carb, not the choke.
As someone said, the heat riser will cause moisture to be trapped in your passenger side muffler and it will rust sooner than the driver's side. The exhaust note also sounds muted on the passenger side until the heat riser opens as well. My cars run fine without a heat riser. And I don't have to worry about them sticking closed, as I've had some do and block one side of the exhaust even when warm. My personal feeling is that heat going under the manifold is also what causes the orange paint to flake off of the intake manifold on the 300 and less hp cars.
It's your car and your choice and you're free to do whichever pleases you.
As someone said, the heat riser will cause moisture to be trapped in your passenger side muffler and it will rust sooner than the driver's side. The exhaust note also sounds muted on the passenger side until the heat riser opens as well. My cars run fine without a heat riser. And I don't have to worry about them sticking closed, as I've had some do and block one side of the exhaust even when warm. My personal feeling is that heat going under the manifold is also what causes the orange paint to flake off of the intake manifold on the 300 and less hp cars.
It's your car and your choice and you're free to do whichever pleases you.
Race Director
Joined: Jun 2006
Posts: 17,901
Likes: 751
From: Inverness FL
St. Jude Donor '07
Le Mans Master
Joined: Dec 2007
Posts: 8,000
Likes: 659
From: Puget Sound
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
'66 choke may still work without a heat riser but I'd expect the action to be delayed. I think not having a working choke is not a big deal anyway. Might cause you not to get a blue ribbon but......................
Last edited by MikeM; Feb 1, 2018 at 07:15 AM.
Team Owner
Joined: Jul 2006
Posts: 22,206
Likes: 4,191
From: Kannapolis NC
'66/later, the choke coil was moved to the exhaust crossover on the manifold. Unlike '65.
'66 choke may still work without a heat riser but I'd expect the action to be delayed. I think not having a working choke is not a big deal anyway. Might cause you not to get a blue ribbon but......................
'66 choke may still work without a heat riser but I'd expect the action to be delayed. I think not having a working choke is not a big deal anyway. Might cause you not to get a blue ribbon but......................
Cruising
Joined: Sep 2011
Posts: 11
Likes: 1
From: wildwood Mo.
wolfman74c
only need it if you are using a choke? and if you have and intake that is not blocked off like most performance aluminium are. Plus the better drive ability when it is cooler temps when it is installed.
Le Mans Master
Joined: May 2000
Posts: 8,729
Likes: 1,508
From: Redmond WA
By contrast an electric choke doesn't get any feedback and won't know that you removed the heat riser and so will not be calibrated correctly, whereas the divorced one can compensate.
Random tip: when I installed an electric choke I ran the ground wire to an idiot light oil pressure sensor. That way the electric choke heater only heated itself if the engine was actively running, as opposed to just the key being on.
Last edited by davepl; Feb 1, 2018 at 11:23 AM.
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