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| | | | Joined: May 2007 Posts: 1,718 Moderator: 60-66 Trucks; North Eastern Bolters | | Moderator: 60-66 Trucks; North Eastern Bolters Joined: May 2007 Posts: 1,718 | Stovebolt,
Simple stuff.
Not sure what the valve in the exhaust manifold is called, or what is does, but I would like to know more. I thought it might choke the exhaust until things got warm and then open to the exhaust pipes. Does it effect starting or engine performance when cold?
HB | | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | You are referring to the heat riser valve. It closes when cold & partially blocks the exhaust sending some of it through the passages in the intake manifold. This warms the incoming fuel/air mixture & gives better running & better gas mileage. As the engine warms up the thermostatic spring relaces & the valve opens. The butterfly is also mounted off center so it also opens under hard acceleration. I hope that explains it.
George
Last edited by Wrenchbender Ret.; 07/17/2017 1:05 PM.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: May 2007 Posts: 1,718 Moderator: 60-66 Trucks; North Eastern Bolters | | Moderator: 60-66 Trucks; North Eastern Bolters Joined: May 2007 Posts: 1,718 | Thanks guys. That answers it. | | |
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