1 2
Tim Suddard
Tim Suddard Publisher
3/25/21 3:15 p.m.
feature_image

Although the folks at Cobra Automotive make their own equal-length headers, shop president Curt Vogt considered our needs and budget and admitted that our Mustang didn't need this rather costly setup.

He suggested that we order a set of Hooker headers—part No. 6901, $498.95 at …

Read the rest of the story

dean1484
dean1484 MegaDork
3/25/21 4:32 p.m.

How much would a set of custom welded headers cost?  How hard would it have been to roll your own with a header kit and a tig.  I was with you until you bent them to access the spark plugs. Yes I know the it has a minimal if any effect on performance but it just looks bad to me. Call it header OCD on my part. And besides I would have liked to read your impressions of trying to build your own from one of those header kits I see used in builds.  That would have been an interesting read. 
 

There has to be a manufacturer out there that makes a header that you don't have to bend to fit. To me that is poor design on the manufacturers part. Even if it cost another couple hundred bucks to get a properly engineered set to me it would have been my choice as every time you open the hood people will see the deformed pipes. (That OCD thing I have again). 

DjGreggieP
DjGreggieP HalfDork
3/25/21 5:04 p.m.

I think once they get back from coating, they'll look like the were built to be like that.

I think the biggest thing is with the advancements in spark plug longevity, most street driven vehicles with headers probably won't see a plug change during the original installers ownership, so ease of accessibility for maintenance probably rates low priority during the designing phase.  

FMB42
FMB42 Reader
3/25/21 5:21 p.m.

Store-bought headers are both great and not so great in my limited header experience ('65 GTO and '67 SBC powered Skylark). But, as Djg above says, greatly extended spark plug life makes a big diff in some ways. Note: store-bought headers were a life saver on many RVs of the 70s, 80s, and 90s,etc (cracked OEM cast iron exh manifolds were a very common RV problem back then).

L5wolvesf
L5wolvesf HalfDork
3/25/21 7:37 p.m.

If rust inside the header tubes can cost power anywhere from 5 to 15 how much would large dents in the tubes cost?

NOT A TA
NOT A TA SuperDork
3/25/21 7:53 p.m.

In reply to L5wolvesf :

https://www.bing.com/videos/search?q=youtube++dented+header+test&docid=607988612658657263&mid=8550742B373685B9D5618550742B373685B9D561&view=detail&FORM=VIRE

Pete. (l33t FS)
Pete. (l33t FS) MegaDork
3/25/21 10:10 p.m.

"Collector gaskets always leak in racing use" is three words too many smiley

 

I've had headers with the little rings on the head side "for extra sealing" turn out to have the rings miss common header gaskets at the corners.  Need to grind the weld ring down a little for a nice V-notch, weld it larger, then file it flat again.

dean1484
dean1484 MegaDork
3/26/21 7:51 a.m.

Collector gaskets work fine if you get quality gaskets and quality clamping ring on both the header/collector and the pipe. The problem is cheep headers are cheep and this is just one more area where you get what you pay for. 
 

With all the mods they made to those headers better quality ones may have actually been cheeper/better. 

dean1484
dean1484 MegaDork
3/26/21 7:57 a.m.
L5wolvesf said:

If rust inside the header tubes can cost power anywhere from 5 to 15 how much would large dents in the tubes cost?

I have never heard of that before but it has me thinking that it would have been cheeper to just get a decent set of stainless steal headers and do the WD40 trick to get that cool gold bronz finish. Versus what ever it will cost to have cheap headers ceramic coated. Both inside and outside. 
 

How do the ceramic coating people know that they get a good coating inside a header?  Run an endoscope down it?  It would be interesting to see how that process is done. 

Sonic
Sonic UltraDork
3/26/21 8:28 a.m.

If you can't dip them then how about pouring the coating in the tubes then covering all the openings and rolling the headers around to all possible angles in your hands so that it spreads around, then uncover the openings and drain (into the other header)

noddaz
noddaz UltraDork
3/26/21 12:02 p.m.

I must be out of touch, but nearly $500 for a set of headers isn't cheap.    But I am probably out of touch.  

Pete. (l33t FS)
Pete. (l33t FS) MegaDork
3/26/21 12:06 p.m.
noddaz said:

I must be out of touch, but nearly $500 for a set of headers isn't cheap.    But I am probably out of touch.  

Most headers I installed for rare, esoteric vehicles like '69 Camaros and late 60s GM A-bodies were $750, ten or so years ago.  This was for coated headers.

 

And the Camaro, at least, needed the collector mooshed for clearance.

docwyte
docwyte PowerDork
3/26/21 2:03 p.m.

I think on Engine Masters they dented the living snot out of a set of headers and then ran them on the dyno.  Much to my surprise, the dents made almost NO difference in power output.

Pete. (l33t FS)
Pete. (l33t FS) MegaDork
3/26/21 2:07 p.m.

In reply to docwyte :

I wonder if the difference is that rust is all through the pipe, interfering with the flow everywhere, while a clearance dent just looks like another bend as far as flow is concerned.

GCrites80s
GCrites80s HalfDork
3/26/21 2:47 p.m.
dean1484 said:

How much would a set of custom welded headers cost?  How hard would it have been to roll your own with a header kit and a tig.  I was with you until you bent them to access the spark plugs. Yes I know the it has a minimal if any effect on performance but it just looks bad to me. Call it header OCD on my part. And besides I would have liked to read your impressions of trying to build your own from one of those header kits I see used in builds.  That would have been an interesting read. 
 

There has to be a manufacturer out there that makes a header that you don't have to bend to fit. To me that is poor design on the manufacturers part. Even if it cost another couple hundred bucks to get a properly engineered set to me it would have been my choice as every time you open the hood people will see the deformed pipes. (That OCD thing I have again). 

Thing is, they can't design headers for every possible set of heads out there. The heads on this engine are a different casting than stock. All kinds of things can move around including the spark plug hole, the spark plug angle, exhaust port height etc.

84FSP
84FSP UltraDork
3/26/21 3:23 p.m.
L5wolvesf said:

If rust inside the header tubes can cost power anywhere from 5 to 15 how much would large dents in the tubes cost?

A number of independent tests showed the dents cost no hp as long as they are reasonable smooth.

wspohn
wspohn SuperDork
3/27/21 12:46 p.m.

One has to watch for finish quality. I've seen aftermarket headers tack welded in four places on the outside and then a more continuous weld on the inside, but incompletely ground to gasket size.  I've even seen headers with rectangular ports that had the rectangle skewed from the angle they had to be.

By all means have the finished product coated as it protects them, but never use header wrap on uncoated steel, or you'll soon be buying another set.

dean1484
dean1484 MegaDork
3/27/21 1:17 p.m.
GCrites80s said:
dean1484 said:

How much would a set of custom welded headers cost?  How hard would it have been to roll your own with a header kit and a tig.  I was with you until you bent them to access the spark plugs. Yes I know the it has a minimal if any effect on performance but it just looks bad to me. Call it header OCD on my part. And besides I would have liked to read your impressions of trying to build your own from one of those header kits I see used in builds.  That would have been an interesting read. 
 

There has to be a manufacturer out there that makes a header that you don't have to bend to fit. To me that is poor design on the manufacturers part. Even if it cost another couple hundred bucks to get a properly engineered set to me it would have been my choice as every time you open the hood people will see the deformed pipes. (That OCD thing I have again). 

Thing is, they can't design headers for every possible set of heads out there. The heads on this engine are a different casting than stock. All kinds of things can move around including the spark plug hole, the spark plug angle, exhaust port height etc.

Why I was wondering if in this case a roll your own option would have been better. 

GCrites80s
GCrites80s HalfDork
3/27/21 3:42 p.m.

I suppose that would be a different article. I don't remember the last time they did a DIY headers article but I do remember them doing at least one.

noddaz
noddaz UltraDork
3/27/21 6:26 p.m.
Pete. (l33t FS) said:
noddaz said:

I must be out of touch, but nearly $500 for a set of headers isn't cheap.    But I am probably out of touch.  

Most headers I installed for rare, esoteric vehicles like '69 Camaros and late 60s GM A-bodies were $750, ten or so years ago.  This was for coated headers.

 

And the Camaro, at least, needed the collector mooshed for clearance.

Ok, I finally had to look.  The expensive (to me) headers are because:

1) They are Hooker Headers

2) The headers are coated

3) I am out of touch with header pricing

I did see headers listed for as cheap as $182.95.  And since I have not bought headers for over 20 years I guess I will go with #3 above.

GCrites80s
GCrites80s HalfDork
3/27/21 7:52 p.m.

I think I got a set of '69 Chevelle headers for $69.99 back in the late '90s from ASAP if anybody remembers them. I'm sure some older users rememberer getting headers for like $35.

philacarguy
philacarguy New Reader
3/28/21 8:37 p.m.

My question is, how do you keep spark plug wires/boots from frying with the headers this close?

Totally agree with the comments about starting with headers that are a better fit.  

Pete. (l33t FS)
Pete. (l33t FS) MegaDork
3/28/21 8:45 p.m.
philacarguy said:

My question is, how do you keep spark plug wires/boots from frying with the headers this close?

 

Heat sleeves.

Had a regular customer with a street rod that had shorty headers where the plug wires were very close, kept burning them, so we installed heat sleeves.  Never an issue ever again, even though the sleeves themselves were burnt white where they touched the headers.

Had another car with an LT1 where, thanks to the different plug angle on the aftermarket heads, the #7 plug was so close to the header tube that you could not remove the spark plug without removing the header, it bottomed against the tube before it was fully unthreaded.  (But remember, Chevys are easy to work on)  The plug boot was in hard contact with the header tube.  With a heat sleeve, it was never an issue, and this was on a 700hp supercharged engine.

 

I figure the D in "DEI" stands for Dark-arts, the way their products work.

malibuguy
malibuguy HalfDork
3/29/21 7:52 a.m.

Never had a problem with Remflex gaskets in extreme use, but slip fits are easy to work with.

And to touch base with a comment above, custom headers can add up REAL quick especially an in-chassis set, and add on top if you want top quality materials, TIG welding with backpurge (if stainless).  For alot of applications its just more cost effective to take an existing set thats close enough and then make the necesary modifications.

Another note, worrying about equal length headers on a dual-plane v8 is pretty useless as they are very insensitive to header lengths differences to one or another, testing has shown differences up to like 8-10" between runners has showed no real difference in power output.  Your better off chasing smooth bends and better chassis fitment.

Here is a few headers I built just to add some porn

 

Tim Suddard
Tim Suddard Publisher
3/29/21 9:58 a.m.

Custom headers would have been at least twice the price. While these headers took more work than I anticipated, I felt a lot of people might want to learn how to make adjustments to their headers.

The headers are now coated and look beautiful again.

 

1 2

You'll need to log in to post.

Our Preferred Partners
4FJqsdoqrWP5y8akZczGX9hJsVR9e05aTQcJiuERP2IHWzUH1VmSAqR5obzCZ30a