what is this vacuum for
Thread Starter
Heel & Toe
Joined: Sep 2017
Posts: 18
Likes: 1
From: Newfane New York
what is this vacuum for
I have a 1977 corvette dual exhaust On the passenger side of engine bay is this unhooked up part. I need to know what it is . If its needed. And if not how to remove it
Thanks
Thanks
Le Mans Master
Joined: Oct 2006
Posts: 7,123
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From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Heat riser. Big chance that it won't work even if it was connected. The butterfly valve at the lower end of that rod is most likely seized. As long as it's in the open position it will be OK.
The function is to force hot exhaust gas back thru the intake under the carb to help warmup and emission.
The function is to force hot exhaust gas back thru the intake under the carb to help warmup and emission.
Thread Starter
Heel & Toe
Joined: Sep 2017
Posts: 18
Likes: 1
From: Newfane New York
It was like this when I bought the car there is no catalytic converter ,dual exhausts and the carb is a newer edlebrock with electronic choke.
I guess my question is seeing it does nothing does it have to stay on the car and if not how hard is it to remove it
I guess my question is seeing it does nothing does it have to stay on the car and if not how hard is it to remove it
Safety Car
Joined: Oct 2007
Posts: 4,378
Likes: 1,740
From: Seattle Area Washington
It is called the EFE Actuator. It opens and closes the heat riser below. It's normal position connected is open so you're OK running as is. Removing it and heat riser will leave a gap between your existing exhaust and manifold. A good exhaust shop can cut and extend your current pipe to match. You will have longer than normal studs from your exhaust manifold on that side. Check the studs before you remove anything, they may be damaged and this opens up a new can of worms. If you can get a spacer use it.
Using a hand vacuum pump, pull a 15" vacuum on the actuator. If the linkage moves and holds 15" of vacuum for a minute the actuator is good.
If the actuator is good and you do remove it, keep all the parts together. They are worth more that way.
Brian
Using a hand vacuum pump, pull a 15" vacuum on the actuator. If the linkage moves and holds 15" of vacuum for a minute the actuator is good.
If the actuator is good and you do remove it, keep all the parts together. They are worth more that way.
Brian
Last edited by bmotojoe; Nov 20, 2017 at 04:53 PM.
Instructor
Joined: Aug 2017
Posts: 180
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From: Jacksonville Florida
