Dougs Headers '77 C3
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Dougs Headers '77 C3
I took the plunge and bought a set of Doug's Header's and side pipes. I watched videos, read articles, posts on this forum... first the article that said this is a easy 4 hour job is FULL OF CRAP! 
Someone also said they didn't have any problems putting the headers on....
First issue I ran into was the screws for the rocker trim. The screws weren't original on the passenger side and were a pain to get out, and the driver side were all seized up. After some KR-oil and a few cuss words I finally got them off. First thing I noticed is the lower rocker area was already cut out at the front. I am thinking at one time this car must have had side pipes on it. The 'stock' exhaust looked like it wasn't 40 years old and the clamps and brackets came off really easy. I finally got the passenger exhaust manifold off- several of the bolts were finger tight at best. The driver's side... still on. I have one bolt that is rounded off and can't get it off. Looks like I'm going to have to take the steering box off to get to it. Any tips on that?
Also, how in the world do you get a torque wrench on the header bolts! I'm not sure I'm going to be able to even get a socket on them! I have them in but loose.
Someone also said they didn't have any problems putting the headers on....
First issue I ran into was the screws for the rocker trim. The screws weren't original on the passenger side and were a pain to get out, and the driver side were all seized up. After some KR-oil and a few cuss words I finally got them off. First thing I noticed is the lower rocker area was already cut out at the front. I am thinking at one time this car must have had side pipes on it. The 'stock' exhaust looked like it wasn't 40 years old and the clamps and brackets came off really easy. I finally got the passenger exhaust manifold off- several of the bolts were finger tight at best. The driver's side... still on. I have one bolt that is rounded off and can't get it off. Looks like I'm going to have to take the steering box off to get to it. Any tips on that?
Also, how in the world do you get a torque wrench on the header bolts! I'm not sure I'm going to be able to even get a socket on them! I have them in but loose.
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Joined: Mar 2017
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From: Virginia
It's an easy 4 hour job if you don't run into problems. I already had the steering box out of the car, though. One of the steering box bolts needed to be cut, and a replacement inserted from the other direction, as it didn't clear the fiberglass. I ended up drilling out most of the side trim screws, and will have to come up with a clever solution to remount them someday.
I used ARP stainless studs. I could then get a socket on most of the bolt heads, and an open-end wrench on the rest. Next time, I'll use the ARP studs with the undersized nut (3/8 stud into the head, 5/16 out of the head to accept the nut).
I used ARP stainless studs. I could then get a socket on most of the bolt heads, and an open-end wrench on the rest. Next time, I'll use the ARP studs with the undersized nut (3/8 stud into the head, 5/16 out of the head to accept the nut).
Team Owner
Joined: May 2001
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From: Western NY
It's a 4 hour INSTALL..........not 4 hours, including the removal of the original exhaust system.
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I agree... in fact I'd say install could be less than 4 hours if everything lines up.
NAPA saved the day! They had a set of Irwin bolt easy outs and it broke it loose enough that a couple turns and then I could get a wrench on it and got it out! The passenger side header is already on but nothing is tightened up yet. Just have to do the driver's side now. Like I mentioned, someone had already made some cuts on the rocker area and I had no problem with clearance even if they weren't already cut out.
A few more leaks to tackle, get the doors aligned (new hinge pins and bushings) and then strip it down, fix a few cracks and then it's time for paint!
NAPA saved the day! They had a set of Irwin bolt easy outs and it broke it loose enough that a couple turns and then I could get a wrench on it and got it out! The passenger side header is already on but nothing is tightened up yet. Just have to do the driver's side now. Like I mentioned, someone had already made some cuts on the rocker area and I had no problem with clearance even if they weren't already cut out.
A few more leaks to tackle, get the doors aligned (new hinge pins and bushings) and then strip it down, fix a few cracks and then it's time for paint!
Team Owner
Joined: May 2001
Posts: 87,323
Likes: 1,587
From: Western NY
I agree... in fact I'd say install could be less than 4 hours if everything lines up.
NAPA saved the day! They had a set of Irwin bolt easy outs and it broke it loose enough that a couple turns and then I could get a wrench on it and got it out! The passenger side header is already on but nothing is tightened up yet. Just have to do the driver's side now. Like I mentioned, someone had already made some cuts on the rocker area and I had no problem with clearance even if they weren't already cut out.
A few more leaks to tackle, get the doors aligned (new hinge pins and bushings) and then strip it down, fix a few cracks and then it's time for paint!
NAPA saved the day! They had a set of Irwin bolt easy outs and it broke it loose enough that a couple turns and then I could get a wrench on it and got it out! The passenger side header is already on but nothing is tightened up yet. Just have to do the driver's side now. Like I mentioned, someone had already made some cuts on the rocker area and I had no problem with clearance even if they weren't already cut out.
A few more leaks to tackle, get the doors aligned (new hinge pins and bushings) and then strip it down, fix a few cracks and then it's time for paint!
Race Director
Joined: May 2006
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Nobody uses a torque wrench on header bolts.
Assuming you are using a fiber type gasket they supply, soak it in water for about 10 minutes.
Tighten the center bolts first and work your way to the outer bolts.
My bolts have 7/16" heads so I cut the closed end off a combo wrench so I had more clearance using the open end between the pipes.
Recheck the bolts after 100 miles and periodically afterward.
Assuming you are using a fiber type gasket they supply, soak it in water for about 10 minutes.
Tighten the center bolts first and work your way to the outer bolts.
My bolts have 7/16" heads so I cut the closed end off a combo wrench so I had more clearance using the open end between the pipes.
Recheck the bolts after 100 miles and periodically afterward.
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Intermediate
Joined: May 2020
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Well... nothing went right with the Driver's side. In fact I think I have to take the header back off and remove the steering box, something is binding up. I have all the bolts in, but they won't pull the header up tight on the block.
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Race Director
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From: Virginia
Post some photos! Sometimes Forum members spot things in photos that you miss in-person.
Pro
Joined: Jul 2012
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From: St. Petersburg Florida
Nobody uses a torque wrench on header bolts.
Assuming you are using a fiber type gasket they supply, soak it in water for about 10 minutes.
Tighten the center bolts first and work your way to the outer bolts.
My bolts have 7/16" heads so I cut the closed end off a combo wrench so I had more clearance using the open end between the pipes.
Recheck the bolts after 100 miles and periodically afterward.
Assuming you are using a fiber type gasket they supply, soak it in water for about 10 minutes.
Tighten the center bolts first and work your way to the outer bolts.
My bolts have 7/16" heads so I cut the closed end off a combo wrench so I had more clearance using the open end between the pipes.
Recheck the bolts after 100 miles and periodically afterward.
I've never heard of that. What soaking the gasket do?
Advanced
Joined: Nov 2016
Posts: 95
Likes: 28
From: Southern MD
I had a similar experience with the drivers side on a 454. I think the header flange is not welded at the proper angle. I fought with mine sure that I had something stopping it from getting home. Finally after recognizing nothing was in the way, I did a little "EB spring fit" ( a term referring to how Electric Boat Shipyard pipefitters would spring a pipe 2 feet and bolt it together. It made for an exciting time when disassembling and reassembling them) slowly drawing the flange up to the block. I don't particularly like that approach but sometimes you have to do what you have to do. I would look at all of your clearances before pulling the box. I've done Hooker Super Comp sidemounts twice. The first set went on easy. The second set of Hookers did not. Doug's headers have been relatively smooth with the exception of the flange thing.
Team Owner
Joined: May 2001
Posts: 87,323
Likes: 1,587
From: Western NY
Just a suggestion.....If I were in the position where I had to use any serious amount of force on header bolts, to draw them into position, I'd consider installing studs into the cylinder head. Bolts are rather small diameter fasteners, and I wouldn't want to either strip the threads in the head, or snap off a bolt.
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I also just noticed that the header pipe that comes out the side of the car is 1 1/4" out on the passenger side, and 1 3/4" out on the drivers side. Why would it be a half an inch off and is that going to be an issue mounting the side pipes?
Race Director
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From: Virginia
One other possibility is that your drivers side engine mount is shot. You'll want to correct this first. I put in Moroso solid engine mounts. YMMV.
Last edited by Bikespace; May 28, 2020 at 06:18 PM.
Burning Brakes
Joined: Jan 2003
Posts: 961
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From: Frederick MD
The motor in my brothers car is actually a 454 out of a mid 70’s pickup (emission engine) so something weird like that doesn’t surprise me at all with that car. Check that and see. It wouldn’t surprise me I
Last edited by kossuth; May 29, 2020 at 07:38 PM.
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Just did this on my 1974......took me and my son about 3 hours to get the drivers side on....didn't remove the steering box. Had to take the steering lock cable off, water sensors, drain some of the anitfreeze and get the car as high I could so the header would fit. Passenger side was so easy that I did it byself.
Team Owner
Joined: May 2001
Posts: 87,323
Likes: 1,587
From: Western NY
Yeah, that's something that "driveway installers" sometimes overlook. YEARS ago, I installed a set of the Hooker "sidemount" headers on a Pontiac Firebird that I used to own. Yes, Hooker made them for most every V-8 powered GM car, back then. The instructions said that the car had to be 3 feet off the ground, in order to be able to get the headers to slide under the car, and up into position. They weren't kidding!!
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Thread Starter
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We finally got the headers to line up. It was hitting the steering box and nothing could be done about that other than putting a dimple in the pipe that was hitting. After that it went right up flush. Right now it's getting some touch up paint (I went with the black headers and pipes) and then tomorrow it will get bolted on.
