Just like the title says, this thread is to find out what headers will work...and what will not.
First off, Yes. For $800-$1200 bucks, you can have a set that will fit a C3 with an LS engine. What about for the rest of us guys that don't want to lay a big one down? You know who we are. We're the same bunch of folks that don't want to lay down $1000 or more for a cooling solution. So there simply HAS to be a cheaper (less expensive) way. After all, a header is a header. Nothing more. Nothing less. So lets not put magic fairy dust on it. Keep it simple.

Areas of concern.

This is a big one, but can be whittled down, it just takes figuring some knowns....and some unknowns. The answer to that lies within the quantified knowledge of this forum, and that is a lot of experience and thinking power, so lets start with what we know (or what little I know).

Seems to me the largest area of concern is the steering box. If I were going to start somewhere, I'd probably start with a set of smallblock Chevy headers designed to fit a Camaro. Then, I'd ask one of you that has already tried this to chime in with whether or not they did fit, and if not, why?
Why a Camaro? Because headers for a smallblock Chevy Camaro are CHEAP! Under 2 bills in stainless cheap. So if it's the steering box, I get it. They either will fit or they won't.

However...a lot of folks like me scrapped the clunky steering box and went with a power rack conversion. There's a reason why most cars are power rack today, but that's another story. What's this have do to the equation? IF header fitment was due to the steering box, and with the box removed a set of say Camaro headers WOULD then fit, then there is no reason to think a set of LS Swap stainless steel headers for an early Camaro wouldn't fit, and these can also be had for around 200 bucks, in stainless as well.

But there's more.

Oil Pan issues. I really cant speak much in this department other than to say in a C3 Corvette, specifically a 1974 model with a Steeriods power rack and pinion conversion, when being used on an LS swap, one CAN take that "oh so wicked" Batwing Oil Pan and it works with the swap. I cam attest to that.

So there you have it. I'm tempted to order a set of Camaro LS Swap headers, but thought I better toss the idea here and get YOUR thoughts.
So without further adue...what say you?

 

Wow, must be a big secret! Although I would like to know what $800/$1000 headers do work? and do they come in 1 7/8 size.. ?

OP, did you find a set of headers yet?

 

On my LS swap I used Speedway Motors 1957 LS swap 3/4 length headers with my Borgesen steering box conversion. 1.75 tubes. Driver side fit great. Passenger side the lower tube needed mods. The lower front tube just hit the motor mount area. I modded the tube for clearance. Total of about $400 for headers.

 

When you say "modded" what exactly do you mean? A dimple or a full-on cut out??

 

I had a set of ls Camaro headers from a 98. They fit nice except they needed bent down at the collectors.

 

There is a lot of variables here, engine position in the engine bay, how low Engine is in the engine , are big influences.
There is always a compromise, as everyone knows.
the best fitting headers I have found are of a vf Holden Commodore in the states it is a Chevy SS.
They fit perfectly except they are to low at the collector.
bfit

 

These are about 2” to low

Clearance here looks close there is 3/8” clearance
Headers on 79 ls1 swap heads are Australia made for vf2 HSV

 

I should of answered a while back. In regards to the mod to the tube I started out with just a dent but it just didn't look good. So I did cut out a short section of the tube. I've built a couple sets of headers from scratch so I had some left over tubing. Just changed the direction of the tube a bit. Welded it up and then ground down the welds. Couldn't tell I did anything thing to the header.