Red hot manifold!
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Joined: Jul 2007
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From: Kalamazoo Michigan
Red hot manifold!
Just got back from a cruise tonight and the car seemed pretty warm inside so I thought I'd pop the hood. The exhaust manifold on the passenger side was pretty red. 
The vacuum actuated flap(heat riser valve?) has been disengaged as it had been sticking slightly shut and causing an exhaust leak previously. But that was several miles ago and this is the first time I've noticed this kind of heat considering the weather wasn't that hot today.
I'm wondering if there is a spacer that can replace this flap(valve) so I can get it out completely. Otherwise, I have access to a set of shory headers that I would assume my local exhaust shop can make fit.
Any thoughts?
The vacuum actuated flap(heat riser valve?) has been disengaged as it had been sticking slightly shut and causing an exhaust leak previously. But that was several miles ago and this is the first time I've noticed this kind of heat considering the weather wasn't that hot today.I'm wondering if there is a spacer that can replace this flap(valve) so I can get it out completely. Otherwise, I have access to a set of shory headers that I would assume my local exhaust shop can make fit.
Any thoughts?
Le Mans Master
Joined: Mar 2001
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From: Ann Arbor Michigan
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Joined: Jul 2007
Posts: 88
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From: Kalamazoo Michigan
Thanks Mark/Duke for the replies. I'm going to look into that spacer, probably go to Corvette Central as they are pretty local for me.
Also, I was chatting with a guy today and he mentioned that it may be some unburned fuel burning in the manifold. Anybody ever heard of that? Last week I installed a new cap/rotor and tonight I'm putting in new plugs. Only other thing I can think of is to replace the plug wires.
Also, I was chatting with a guy today and he mentioned that it may be some unburned fuel burning in the manifold. Anybody ever heard of that? Last week I installed a new cap/rotor and tonight I'm putting in new plugs. Only other thing I can think of is to replace the plug wires.
Last edited by MI-CORVETTE; Sep 5, 2007 at 06:23 PM.
Le Mans Master
Joined: Mar 2001
Posts: 6,640
Likes: 287
From: Ann Arbor Michigan
Thanks Mark/Duke for the replies. I'm going to look into that spacer, probably go to Corvette Central as they are pretty local for me.
Also, I was chatting with a guy today and he mentioned that it may be some unburned fuel burning in the manifold. Anybody ever heard of that? Last week I installed a new cap/rotor and tonight I'm putting in new plugs. Only other thing I can think of is to replace the plug wires.
Also, I was chatting with a guy today and he mentioned that it may be some unburned fuel burning in the manifold. Anybody ever heard of that? Last week I installed a new cap/rotor and tonight I'm putting in new plugs. Only other thing I can think of is to replace the plug wires.
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Joined: Jul 2007
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From: Kalamazoo Michigan
Timing might be it
Duke, I just installed plugs and took it for an easy ride. Upon returning home I immediately opened the hood and found that both manifolds are red hot right where all 4 ports come together. The plugs seemed pretty consistently the same color (light tan).
Timing will be the next thing I'll work on. Thanks again, I think you are on to something here.
Timing will be the next thing I'll work on. Thanks again, I think you are on to something here.
Le Mans Master
Joined: Aug 2003
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From: Chattanooga TN
If the flapper is bad anyway I would just modify it. On my TPI truck conversion that's what I did. I took off the flapper valve, removed the actuator, ground the rivets off the flap, removed the flap, removed the rod, used a small "freeze plug" on 1 side and drilled and tapped a bolt into the other side to close up the holes, re-installed it. Cheap fix and works fine.
If both manifolds are glowing red, you have a bigger tune-up issue to solve first.
If both manifolds are glowing red, you have a bigger tune-up issue to solve first.
Race Director
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From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
My first thought were about timing when I read the original post. Give that a look and see where you are. Have you seen Lars Timing Paper? If not we can post a link to it for you. Pretty good read.
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Joined: Jul 2007
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From: Kalamazoo Michigan
Thanks again guys for the help 
and if someone could get me that link to Lars paper Eddie was referring to, that would be great. The wierd thing is that the car seems to run well and the temp guage usually only gets up to about 175 or so. Never has it been above 200 even with the glowing manifolds.
and if someone could get me that link to Lars paper Eddie was referring to, that would be great. The wierd thing is that the car seems to run well and the temp guage usually only gets up to about 175 or so. Never has it been above 200 even with the glowing manifolds.
Racer
Joined: Mar 2006
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From: SAN CLEMENTE CALIFORNIA
Thanks again guys for the help and if someone could get me that link to Lars paper Eddie was referring to, that would be great. The wierd thing is that the car seems to run well and the temp guage usually only gets up to about 175 or so. Never has it been above 200 even with the glowing manifolds.
and if someone could get me that link to Lars paper Eddie was referring to, that would be great. The wierd thing is that the car seems to run well and the temp guage usually only gets up to about 175 or so. Never has it been above 200 even with the glowing manifolds.
