Heddman's 351 style....

[cobraii351]

I used the dreaded Heddman 30s headers on my car. But with the 351's extra height and width I had to do a lot of modifications to them to make them fit the 351. I had changed the top of the #1 tube to clear the frame rail but left the bottom alone. I figured new new V8 A/C front springs I'd be ok. Not even close! So after redoing the bottom 90 twice I decided to make it the way it should have been done in the first place (barring going over the x member like the rest of the pipes). And with new heavier front springs I should be OK.
The main problem is that the 90 bend at the bottom is low and in front of the front tire angle of attack. Meaning anything much higher than a pebble hits the pipe before the tire gets to lift the car over it.
I cut the bottom off and put on 2 45 bends from some old header pipes and with the help of Mike and another garage-mate. This is what we came up with.

Here are pictures of the finished product.

The tire will now roll over anything before the pipe has a chance to hit it. Now If I bottom out and smash this one. I am going to have a lot more than a little header pipe to replace.

Tim

 

[JonDawg]

KOOOOOL!!! wanna make me a set?? But,....it looks like you've got more room B4 the frame rail than i do... any ideas why??

Well, congrats.

Jon.

 

[cobraii351]

I'm not sure what you mean. Do you have a 351? If not remember the 351 is about an inch taller so that would make up for what you are talking about.

Tim

Oopps, I linked the wrong picture in for that last one. Fixed now.

 

[78pinto]

you have lots of room under there! My car is lowered and i have about 3 1/2 to 4 inches of clearance before my headers scrape.....i take it easy over railroad tracks and bumpy streets

 

[dmoody]

It looks like the other header pipes are too close to the fender apron? Man I would not want to have to tighten those header bolts ..whoahisme! I had a hard enough time getting the darn bolts on my 302 headers. It looks like you done some good welding.. did you pressure test it to be sure you didn't have any leaks?

d

 

[JonDawg]

I'm not sure what you mean. Do you have a 351? If not remember the 351 is about an inch taller so that would make up for what you are talking about.

Yeah, its a 351W, stock height everything, and stock E7TE heads. But I have about 1.2" of room between the inner fender and the engine. Maybe its the picture/camera, but it looks like you have 2-3" there.

 

[78pinto]

i have my motor strapped down so i have no movement in the engine/headers

 

[cobraii351]

I'm not sure why things would look different. I'll get some more shots withthe battery out when I get home from this weekend. I'm out of town at the moment. I used the stock mounts and all. I did have to do a little massaging of the left inner fender. The header bolts don't seem any more of PITA than any other header bolts. At least I didn't think so. I did cut the #4 pipe loose and I put in in seperate as well.


Tim

 

[zwhitr]

check out this thread

grind off a llittle on the crossmember and a mini PMGR starter it was good to go except the welding purtiness.

http://forums.stangnet.com/showthread.php?t=362382

 

[dmoody]

As far as the left fender apron, I've thought about cutting the squarish section of the battery box out ..then welding in a flat piece of sheetmetal going down to the top of the frame. My battery is in the trunk now anyway so I don't need it but the extra room would be nice.

For my header bolts I had to buy some crows feet.. but before that I had a u-joint and all kinds of crazy extensions, etc. I can't imagine having even less room, particularly for the bolt that is closest to the power brake booster. That guy is a nightmare to tighten. Anyways nice work on the fabrication.

d

 

[cobraii351]

Hey Z,
I remember that post but I could remember who did it. Because I wanted to see what you did again. Thanks for providing the link. I looked at my car though and I don't think I really have the room with the extra motor. I already had to cut all the pipes at one point or another. I added at least an inch to each pipe to get things so they wouldn't be touching/rubbing on the floor and everything else. the wider of the 351 is easy to deal with the the extra 1" up the makes things a pain.

D,
How do you go about pressure testing things? I ground things off and "inspected" as best I could, touching up where I thought it needed it. But it would be nice to know there are really no leaks.

Thanks,

Tim

 

[zwhitr]

Hey Z,
I remember that post but I could remember who did it. Because I wanted to see what you did again. Thanks for providing the link. I looked at my car though and I don't think I really have the room with the extra motor. I already had to cut all the pipes at one point or another. I added at least an inch to each pipe to get things so they wouldn't be touching/rubbing on the floor and everything else. the wider of the 351 is easy to deal with the the extra 1" up the makes things a pain.

D,
How do you go about pressure testing things? I ground things off and "inspected" as best I could, touching up where I thought it needed it. But it would be nice to know there are really no leaks.

Thanks,

Tim

Glad I could help

You know I was not the first to try it but I wanted it so bad and could just visualize it even when I was in turkey almost convinced a turkish exhaust shop to do it but he refused claimed it would make the stater bad oh well.

I believe Dano 78 did once before.

If you hang around here long enough history repeats itself.. just use the advanced searches either by name or title they work.

 

[Dano78]

Eh? What did I do?

Rework a set of headmans to eliminate the #1 down pipe?... did that..

Fitting them to a 351W?...wellll yeah but not the approach one would have typically done. That and I was fitting them to a 351W annnd an AOD. Talk about going to a gun fight with a pocket knife... I kinda had them fitting but ran into major collector trouble. The porject kinda fizzled since then... But- once my new shop is up, i'm sure I'll be back at work on these crazy ideas of mine.

I don't pressure test the headers. I'll run a flashlight on the backside of the welds, if there's light, it'll be heard. If there's that much pressure on the exhaust side to warrant an pressure test, buddy, you've got system backpressure issues!

Either it was Tim or Darryl that sent me pictures of modified headman headers for a 351W in a two. heck it was back in '99 IIRC, I still have the black and white printouts!.....somewhere... I bet (whoever it was) doesn't remember sending them to me. -lol i was living in Albuquerque at the time.

 

[cobraii351]

Dano,
I do believe that was me. that sent you those "print-outs". Your right that was a while ago. I finally got around to doing the #1 pipe better. After all the car has been sitting for 3+ yearts I figured I better do something about it.

Tim

 

[dmoody]

D,
How do you go about pressure testing things? I ground things off and "inspected" as best I could, touching up where I thought it needed it. But it would be nice to know there are really no leaks.

I read an article in Car Craft about how to build your own headers a couple of months ago and unfortunately my memory isn't that good. :--( However I do remember that they used air pressure in some way to do it. Oh well, wish I could be of more help...

d

 

[cobraii351]

Actually Dano, with the extra width of the 351 the Heddman's might not fit too bad with an AOD. I'll get some better underneith pics if you want. I have a lot of room around the C4 but I know the AOD is a good bit bigger. It might just work though.

Tim

 

[Dano78]

Oh I had the headers fitting somewhat fair with the 351W and AOD. the AOD itself is almost exactly 'twice' the width (at the tranny pan) as the C4. I had the headers fitted but it required cutting off the 3" collector because it ran right into the trans X-member stubs. You know, the parts that reach out to bolt the X-member to. Yeah.. really sucked. The car got junked shortly after and I ended up moving up this way. Once the shop is built I'l get another shell to use to set stuff up with and will be back in business again.

BTW Tim, thanks again for the pics, they proved to be very helpful.

 

[Dano78]

I read an article in Car Craft about how to build your own headers a couple of months ago and unfortunately my memory isn't that good. :--( However I do remember that they used air pressure in some way to do it. Oh well, wish I could be of more help...

d

It's actualy yery simple to make a a pressure testing fixture. Just make a steel cap for the Collector that uses a gasket and bolts on like a collector reducer does and drill a round hole in the center and install an air-line fitting Then make a long plate that covers all the header cylinder head ports and tap and thread it for the header flange bolt pattern. Install the gasket and viola! you have a pressureized header! You can drill and tap either end for a pressure gauge if desired. Piece of cake...