1969 427 Heat Riser Picture
Thread Starter
Burning Brakes
Joined: Feb 2008
Posts: 993
Likes: 44
From: Jefferson Hills PA
1969 427 Heat Riser Picture
I'm looking for a picture of a properly installed heat riser on a 69 427. I have side exhaust but that won't matter on the install. I have two new ones here and don't remember which one is correct for my car. They are "reverse handed" and could be installed in two different directions.
Thanks, Ned
Thanks, Ned
Thread Starter
Burning Brakes
Joined: Feb 2008
Posts: 993
Likes: 44
From: Jefferson Hills PA
Gary, Yes the pictures are a great help. I didn't know which way the weight went, up or down, and which way it faced. I can see by your picture if faces the back of the care. I was trying to put it in towards the right side of the car and the metal peg was hitting the frame.
From what I see in your picture, it looks like the weight hangs down and the spring pressure pulls it up? Is that correct?
Thanks, Ned
From what I see in your picture, it looks like the weight hangs down and the spring pressure pulls it up? Is that correct?
Thanks, Ned
Last edited by NMT1957; May 14, 2013 at 05:24 PM. Reason: Add Text
Melting Slicks
Joined: May 2009
Posts: 3,079
Likes: 315
2024 C3 of the Year Finalist - Unmodified
Ned
Went thru this dilemma twice myself. There are two different heat risers available. This is the correct configuration for your car:
I had better luck keeping the donuts in the car by utilizing taller brass nuts on the stainless studs. The lock nuts were a pain. I also tack welded the valve in the open position. Makes sense in Miami.
Went thru this dilemma twice myself. There are two different heat risers available. This is the correct configuration for your car:
I had better luck keeping the donuts in the car by utilizing taller brass nuts on the stainless studs. The lock nuts were a pain. I also tack welded the valve in the open position. Makes sense in Miami.
Thread Starter
Burning Brakes
Joined: Feb 2008
Posts: 993
Likes: 44
From: Jefferson Hills PA
I had both of these heat risers turned every which way they could possibly fit from upside down to backwards and still didn't know which one was right. I'm working without a body on so it was pretty easy to turn them every way possible. All of the pictures are a big help to me. I also have a set of brass nuts, for the exhaust I mean, and was wondering why they were used by the previous owner. I'm trying to use everything correct but I also have to be practical here. I might put the brass ones on for now since the side exhaust has to come off for the body drop. I can always put the correct ones on later. I didn't want to weld mine open, what's the advantage to it, less restriction? I never thought these big blocks needed any help heating up fast, they do that quite well on their own.
Melting Slicks
Joined: May 2009
Posts: 3,079
Likes: 315
2024 C3 of the Year Finalist - Unmodified
It is extremely difficult to properly seat the exhaust donuts while positioning the welded side exhaust tubes under the covers. A little anti-seize on the donuts works wonders. If you want the car to be correct...as far as judging is concerned...then the stainless studs and brass nuts need to be changed. I just got tired of changing blown-out donuts and the annoying sound of exhaust leaks.
The heat riser will eventually seize and stop operating freely...unless periodically lubricated as stated in the service manual. If it becomes stuck in the closed position...your engine will suffer on one side. I doubt that you will be driving your car in sub-freezing winter conditions...so it really is not required. Some people wire them open. I chose the tack weld method...which can easily be removed. The other choice is to substitute a spacer for the heat riser.
Is your car going to be a driver...or a show car/trailer queen?
The heat riser will eventually seize and stop operating freely...unless periodically lubricated as stated in the service manual. If it becomes stuck in the closed position...your engine will suffer on one side. I doubt that you will be driving your car in sub-freezing winter conditions...so it really is not required. Some people wire them open. I chose the tack weld method...which can easily be removed. The other choice is to substitute a spacer for the heat riser.
Is your car going to be a driver...or a show car/trailer queen?
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Thread Starter
Burning Brakes
Joined: Feb 2008
Posts: 993
Likes: 44
From: Jefferson Hills PA
It's going to be a driver for sure, and I can't imagine ever in cold weather. I don't plan on having it judged by anyone so now I'm really liking the idea of tack welding it open