Dynomax Header fit.....help
Thread Starter
Intermediate
Joined: Jul 2004
Posts: 33
Likes: 1
Dynomax Header fit.....help
Installed a set of ceramic coated Dynomax on my '71 350. No problems with install but noticed when I went to put on the reducer that it comes within 1/2" of hitting the bottom of the foot well. Don't see how an exhaust plus clamp will go on without touching (melting) the fiberglass. Instructions say for fit adjustment to loosen the motor mounts and shift the engine. Never heard of that but maybe can be done.
Anybody incur this problem? What did you do?
Anybody incur this problem? What did you do?
Team Owner
Joined: Jul 1999
Posts: 26,545
Likes: 46
From: Huntersville NC
I might try a thin sheet of stainless to use as a heat shield, maybe try a band clamp, look into welding. I would try many different options before attempting to reposition the engine via motor mounts! 
Burning Brakes
Joined: Jun 2000
Posts: 892
Likes: 0
From: GA
Whooops... I never heard this one before. Mine are on... but my body is not. I hope this isn't an issue. Although I did weld mine after the collector.....
http://temp.corvetteforum.net/c3/bendera/header.jpg
Also... I turned my collector flange so it is flat on the bottom and the peak is at the top ( to ensure clearance) Do I need to spin it around so the body doesn't hit the peak?
http://temp.corvetteforum.net/c3/bendera/header.jpg
Also... I turned my collector flange so it is flat on the bottom and the peak is at the top ( to ensure clearance) Do I need to spin it around so the body doesn't hit the peak?
Thread Starter
Intermediate
Joined: Jul 2004
Posts: 33
Likes: 1
Stewart '74
How close is your reducer to the floor pan?
I see you have an automatic. My brother just installed the same set in his '78 automatic and his clears by 2 1/2 inches. His part number is slightly different as well. Think it is because his is an auto and mine is a 4 spd. I have a call in to Dynomax with no response yet.
Mr. Gearhead, I will let you know what Dynomax says. Is yours a 4 spd?
Measuring from the bellhousing to the collector, the collector is 1 inch closer to the bellhousing on the driver side vs the passenger side putting the passenger side header too close to the floor pan. By the way, what number do you have stamped on the collector. Mine has two numbers on each: 303 on the top and 008 on the bottom. My brothers is 502 and 008. Thanks
How close is your reducer to the floor pan?
I see you have an automatic. My brother just installed the same set in his '78 automatic and his clears by 2 1/2 inches. His part number is slightly different as well. Think it is because his is an auto and mine is a 4 spd. I have a call in to Dynomax with no response yet.
Mr. Gearhead, I will let you know what Dynomax says. Is yours a 4 spd?
Measuring from the bellhousing to the collector, the collector is 1 inch closer to the bellhousing on the driver side vs the passenger side putting the passenger side header too close to the floor pan. By the way, what number do you have stamped on the collector. Mine has two numbers on each: 303 on the top and 008 on the bottom. My brothers is 502 and 008. Thanks
Safety Car
Joined: Aug 2000
Posts: 3,943
Likes: 44
From: Florham Park NJ Port Credit Ontario
Originally Posted by rfun'71
Stewart '74
How close is your reducer to the floor pan?
I see you have an automatic. My brother just installed the same set in his '78 automatic and his clears by 2 1/2 inches. His part number is slightly different as well. Think it is because his is an auto and mine is a 4 spd. I have a call in to Dynomax with no response yet.
Mr. Gearhead, I will let you know what Dynomax says. Is yours a 4 spd?
Measuring from the bellhousing to the collector, the collector is 1 inch closer to the bellhousing on the driver side vs the passenger side putting the passenger side header too close to the floor pan. By the way, what number do you have stamped on the collector. Mine has two numbers on each: 303 on the top and 008 on the bottom. My brothers is 502 and 008. Thanks
How close is your reducer to the floor pan?
I see you have an automatic. My brother just installed the same set in his '78 automatic and his clears by 2 1/2 inches. His part number is slightly different as well. Think it is because his is an auto and mine is a 4 spd. I have a call in to Dynomax with no response yet.
Mr. Gearhead, I will let you know what Dynomax says. Is yours a 4 spd?
Measuring from the bellhousing to the collector, the collector is 1 inch closer to the bellhousing on the driver side vs the passenger side putting the passenger side header too close to the floor pan. By the way, what number do you have stamped on the collector. Mine has two numbers on each: 303 on the top and 008 on the bottom. My brothers is 502 and 008. Thanks
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Thread Starter
Intermediate
Joined: Jul 2004
Posts: 33
Likes: 1
Dynomax called back and sent me a drawing of how the tubes should look to compare to what I have. They said MAYBE they sent the wrong part number for the right side or it was bent incorrectly. They were very pleasant and helpful to this point. They also indicated they would send me a new set if I was not satisfied. We will see once I get home and compare. I will keep you guys posted if they send me a replacement.
Thread Starter
Intermediate
Joined: Jul 2004
Posts: 33
Likes: 1
Dynomax was not so willing to send me a new set on the second day of conversation. They did send me measurements of the collector to the number 8 port and also the measurement of the offset of the collector from mid point. My set checked out fine as far as the measurement goes so there was no need to send a replacement set.
There must be something else different about my setup that makes the clearance tight.
There must be something else different about my setup that makes the clearance tight.
