Hooker headers - super comp to comp swap

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'73 mustang convt.
The tri-power manifold required a swap to 4v heads and exhaust. I was running a 2v Edelbrock performer and some hooker super comp headers. The swap over was a few years back, I don't have any pictures. I had spent so much money on the manifold, the carbs, the heads and such that I 'jumped' at an ebay auction for some used 4v Cleveland Hooker super comp headers. I ran with that for years.

Never buy used headers off of Ebay. The picture looked good but they had been smacked a few times and the fresh coat of paint was good enough to hide in pictures but not in real life. Still, I didn't have the funds to 'do it right' so I slapped them on.

Then a week or so ago I managed to have a stupid moment pulling into a gas station. As I turned left across traffic the bay I had in mind became occupied. I adjusted my course at the last moment but didn't see the curb sticking out. SMACK. I ran over the peninsula and hit the headers HARD. This is no surprise, the 4v super comp headers didn't have much ground clearance. Heck, any speed bump or higher speed dip and it seemed like I would smack them.

The good news is between the headers and the subframe connections I managed to avoid any body damage at all.

Now for some pics:

First the ugly. Here is what a header pipe is NOT supposed to look like:

P1010296.jpg


Here is a shot of the slider bars.. um, I mean sub frame connector. I have a jeep I four wheel with some slider bars, they work great! I never expected the subframe connectors to double up as sliders but, goodness, it saved the floor pans and rockers and such:

P1010297.jpg


Another pic of the header. Horrifying I know...

P1010298.jpg


No damage! Sweet! I had spend a small fortune on some NOS rocker moldings years before they were available aftermarket. Add to that some rocker/fender damage I would have been out a 'not so cool' grand or two.

P1010300.jpg


'The worlds best header to the rescue!'

P1010303.jpg


They were packed great. Really nice job. I have pics but no need to post them.

Let's just jump in and look at the difference between the 4v super comp and the 4v comp

P1010322.jpg


The comp are shorter and not 'tuned'. That means each pipe is not 'exactly' the same length. You will notice they don't take the same path to the collector either.

The tubes are different sizes. 2 inches on the super com, 1 3/4 on the comps.

P1010329.jpg


The super comps really push the outside limits of the port. I had issues getting them to seal and ended up using genuine hooker gaskets. With the smaller pipe size this may not be an issue with the regular comps.

P1010330.jpg


This shot makes it a lot more obvious. You can see the difference between the bolt hole and the primary tube.

P1010331.jpg


Installed you can see the difference in length. The exhaust pipe is hanging down a little but you can see the comps sit a little higher and are quite a bit shorter than the super comps.

P1010334.jpg


Here is a picture from the drivers side. The lowest part of the header cleared the ground by just 4 inches.

P1010340.jpg


I have to take another pic with the new headers. Individual results will vary depending on tire/springs. ;)

The tubes themselves sit about 5" above the groun with the super comps. No wonder I smacked them!

P1010345.jpg


You need a lot more ground clearance for the installation/removal of the super comps than you do for the comps. passenger side is easy but the driver side is a little tricky with the steering stuff in the way. This gives you an idea of how far I jacked it up to get the super comps out. The comps slipped right in no issues.

P1010347.jpg


Yep, that's a pair of blue jeans I used to protect the new headers. Worked pretty good.

It seemed like it was leaning more that the picture shows.

P1010349.jpg


I did learn the trick to jack up the rear axle and get that side off the ground. This puts less strain on the frame jack point. I did it in 'stages'. Rear/body/rear/body/rear/body/rear/body. Same thing letting it down. Took more time but I think it was better overall for my 40 year old car.

Here is the new header installed. Pretty!

P1010357.jpg


This will be what I think is my 4th header set. My first were a used set that didn't have a common flange, the second were some super comps for 2v that I had modified to clear the c6 (I don't think this was necessary now but it did allow for removing the tranny without disconnecting the headers). The 3rd set were the ebay super comps for 4v. They were a little rough to start with but I was trying to save money. I now finally have a beautiful set of ceramic coated headers. I will do some more measurements on ground clearance tomorrow.

Both the super comp and the comp headers cleared the c6 tranny. The passenger side of the comp headers is close but it makes it. I think removal of the tranny is not an issue with the super comps. It might be necessary to remove at least one side of the headers to get the c6 out. Anyone have experience with this?

I did a write up on the stage 8 header bolts. Well worth the effort:

http://www.7173mustangs.com/thread-stage-8-header-bolts

I know this was long. Thanks for reading it. I hope it helps out at least one other member considering/installing hookers.

Keyword search: 6915 6211

 
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So which is better Comps or Super Comps?
Good question! I will get another ground clearance shot with the new headers. I will also report on if it 'feels' different. Up to this morning I was running open headers. It seemed faster but it was probably more the noise factor. Open headers are very very very loud.

 
[align=justify]

Mine were the Hooker Comps 6921 which cost me $229.71. Running them completely open they turned heads and really made me smile. :cool:
yeah, the looks I got in the neighborhood were pretty funny. I set off several car alarms.

First impression is good. Seems a little more torquey. But I also had them put in a equilizer bar (h pipe). What a difference at the tail pipe that makes. No more phat phat sounds at idle. Smooth. Seems quieter too. That might be the thicker pipes, the ceramic coating, the h pipe or a combo of all three.

It's not running 100 percent. I have to check the plugs, too much gas smell. Maybe a crossfire or a loose plug or ?? Still hauls butt. ;)[/align]

 
Looks to me like the smaller ones are for the 2V heads. I have the regular Hooker headers on my 4V and they are 1 3/4". The openings are still larger than the ones you are showing. I hope you did not buy the wrong ones :huh: The exhaust ports on your 4V heads are bigger than the size of the opening on those headers, I would think that would be a big flow problem, and choke off performance.:(

 
Looks to me like the smaller ones are for the 2V heads. I have the regular Hooker headers on my 4V and they are 1 3/4". The openings are still larger than the ones you are showing. I hope you did not buy the wrong ones :huh: The exhaust ports on your 4V heads are bigger than the size of the opening on those headers, I would think that would be a big flow problem, and choke off performance.:(

Got this at Clevelands forever:

EXHAUST NOTE: Rule of thumb, primary tube ID=exhaust valve diameter + 10%. Ex. 1.7”X1.10=1.87 or 1 7/8” primary tube header....jim

 
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Looks to me like the smaller ones are for the 2V heads. I have the regular Hooker headers on my 4V and they are 1 3/4". The openings are still larger than the ones you are showing. I hope you did not buy the wrong ones :huh: The exhaust ports on your 4V heads are bigger than the size of the opening on those headers, I would think that would be a big flow problem, and choke off performance.:(

Got this at Clevelands forever:

EXHAUST NOTE: Rule of thumb, primary tube ID=exhaust valve diameter + 10%. Ex. 1.7”X1.10=1.87 or 1 7/8” primary tube header....jim
So if a 2" primary on the super com and 1 3/4" on the comps, then supers are 1/8" too big and comps are 1/8" too small.

 
Looks to me like the smaller ones are for the 2V heads. I have the regular Hooker headers on my 4V and they are 1 3/4". The openings are still larger than the ones you are showing. I hope you did not buy the wrong ones :huh: The exhaust ports on your 4V heads are bigger than the size of the opening on those headers, I would think that would be a big flow problem, and choke off performance.:(

Got this at Clevelands forever:

EXHAUST NOTE: Rule of thumb, primary tube ID=exhaust valve diameter + 10%. Ex. 1.7”X1.10=1.87 or 1 7/8” primary tube header....jim
So if a 2" primary on the super com and 1 3/4" on the comps, then supers are 1/8" too big and comps are 1/8" too small.

I think a rule of thumb is just that. Personally I've always wondered where header co's, and others, come up with sizes and lengths and all that. Thought that this helps get an idea where to start. You'll be in a position to judge the difference between the two. I remember reading some where that shortys aren't any better than stock exhaust. My worn out sb would disagree, but damn, some of those rice'rs haul...jim

 
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Got this at Clevelands forever:

EXHAUST NOTE: Rule of thumb, primary tube ID=exhaust valve diameter + 10%. Ex. 1.7”X1.10=1.87 or 1 7/8” primary tube header....jim
So if a 2" primary on the super com and 1 3/4" on the comps, then supers are 1/8" too big and comps are 1/8" too small.

I think a rule of thumb is just that. Personally I've always wondered where header co's, and others, come up with sizes and lengths and all that. Thought that this helps get an idea where to start. You'll be in a position to judge the difference between the two. I remember reading some where that shortys aren't any better than stock exhaust. My worn out sb would disagree, but damn, some of those rice'rs haul...jim
Ha, Ha !!! I don't know anything about the formula, I am just going by what I see in the photo's !!:cool:

 
WILL E,

I HAVE TO AGREE WITH T.KLAPPERICH THAT YOU'VE GOT HEADERS FOR A 2V HEAD. I'M SURPRISED THAT YOU GOT THOSE TO SEAL. MAYBE YOU DID BETTER WHEN YOU GOT THOSE HEADERS OFF OF EBAY. SORRY MAN :( VERY NICE LOOKING MUSTANG.

 
Well, that would be a bummer.

Part No 6915-1HKR

Flange also had 6915 stamped on it.

I didn't buy them from summit but here is a link:

http://www.summitracing.com/search?keyword=6915-1HKR&dds=1

The 2v part number is 6921. But both share the same primary tube size.

Summit didn't show a 'super comp' header for the 2v, the 2" primary tube size is probably too large for a 2v but interstingly there are a lot of 'super comp' headers that have a smaller tube size.

Here is a listing of supercom headers from Holley's web site:

http://www.holley.com/types/Super%20Comp%20Full%20Length%20Headers%20-%20Ford%20Mercury.asp

The primary tube sizes seem to vary. 2.12 being the largest (for the 428)

They are the 'correct' headers for the 4v. Now, are they the 'best'? That's a good question.

Headman uses a 1 5/8 primary for their 2v header, I didn't see a 4v header.

FPA didn't seem to provide the spec, here is a pic:

http://www.fordpowertrain.com/351C.htm

Generally a smaller tube will help with the lower end torque, bigger tubes are better for HP at higher RPM's. The car does feel more torquey, the crossover pipe probably helped with that too. And I don't 'feel' a loss at the higher RPM's but I don't spin the motor past 5500, and rarely even go there. No problem with the head sealing. The included holley gaskets matched the holley gaskets I had used with the super comp.

As always it's the matching of parts that matter. It would take trial and error, some standard measurement (chassis dyno being the best) and a lot of money to try each header type for a specific engine setup. For each one you would have to rejet carbs, change the timing, etc. Time and money!


Hey, totalled, what part number are those? I can't quite make it out on the flange? Can I get a picture of the entire header? Maybe I have the 'correct' part but they put the wrong flange on???



These are my new set of 4V comps. They do look a bit larger than the headers he put in, or at least the ports have cleaner finish work...

IMG_0036.jpg


IMG_0037.jpg
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Hey, totalled, what part number are those? I can't quite make it out on the flange? Can I get a picture of the entire header? Maybe I have the 'correct' part but they put the wrong flange on???

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Here is a better 'side by side' of the super comp and comp headers

P1010329.jpg


You can see the larger tubes, the larger opening and the smaller welds.

Here is a picture similar to yours

P1010310.jpg


 
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