03 Cobra Exhaust Manifold Steering Mods V2.0 Thanks M_Maker!!

94m5

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Ok,

Instead of sorting and culling the bull:q:q:q:q from the last thread, I did away with the old one in it's entirety.

DLF, GMAN, and ummmmm, 97mark something or other?(sorry), I'm sorry that you had to suffer through that :q:q:q:q. Doug in piticular, I appriciate your insight torwards improving something you see room for improvment in.


Now, ALL douchebaggery aside.....Lets get to it.
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This thread is dedicated to the mods needed to adapt Cobra manifolds to the MarkVIII platform.

All of the parts for the column are available from Summit Racing. (I'll get part #s later.)

Flaming Rivers Steering joint (36spline/3/4"DD)
Borgeson 36 Spline steering shaft (8")
Borgeson 36 Spline female to female coupler

The Dipstick is another place where you will run into an issue. With the MarkVIII engine, the stock dipstick won't clear the new manifolds. We also had an issue with a mach1 dipstick hitting the VIII Motor mount. (trial and error will dictate how you get around that.)

That's all *I* have at this point. I'll add more as we go along.

Mike

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Not block blocking. Wasn't there a long ago thread on a member cutting up two driver side manifold to make on driver side manifold to fi.
 
I have a few photos of Jeremi's install and that shaft looks pretty much identical to what he used. He never mentioned anything about the dip stick tube, although knowing him, he probably had a fix worked out in a few seconds. ;)

I have a set of the 03 Cobra manifolds as well and am really confused about how the shaft goes together. Doug, can you please post your pics again and maybe explain how the telescoping part of the shaft works? Do you lose it when you replace this part of it? Is it better to use the splined shaft as opposed to a DD shaft? I kind of figured the DD would be better for drilling for the set screws.
 
you replace the collapsible lower part of the shaft and stock rag joint with the shaft pictured above and the flaming rivers joint.

Jegs parts numbers:
898-FR1715DD
153-313434
153-409208

When working on the dipstick tube, the info I got from ford was that 93-96,97, and 98 mark viii's all have a different tube number. I ordered an 03 tube, which cleared the manifold but hit the mark viii motor mount. In the end I bent the 97 mark viii tube that I had.

Jeremy helped me with this alot after i ran into problems. He has my thanks and should get the credit for this. Jeremy didn't recall any dipstick fitment issues from his install, but wasn't sure if he used a Mach 1 tube or the 98 mark viii.
 
Great info.
Thanks Mike.

So I understand non-terminator cobra manifolds have smaller ports but look identical to 03/04 manifolds.
Anyone know how much smaller?
Is it worth the effort for NA marks to go with pre-terminator manifolds?
 
Doug, can you please post your pics again and maybe explain how the telescoping part of the shaft works? Do you lose it when you replace this part of it? Is it better to use the splined shaft as opposed to a DD shaft? I kind of figured the DD would be better for drilling for the set screws.

As requested.

A complete (slightly modified) stock steering shaft is in the first pic, and shown disassembled in the second pic.

The upper shaft is at the top of the 2nd pic, the lower at the bottom.

Normally, the upper shaft fits into the lower, as a slip joint, and you get a few inches of play in the length of the overall shaft.

Using the new shaft as diagramed, you'd connect the new joint to the right end of the upper shaft in the 2nd pic, and then attach the new splined connector to the steering rack stub.

I'd recommend using a portion of the old lower shaft as a sleeve over the upper shaft above the new joint so that the original plastic sealing tube could be retained.

Just in case anyone is wondering why I modified my steering shaft, it was to gain a bit of header clearance on my SC (3rd pic). And yes, the Thunderbird and Mark VIII steering shafts are the same. :rolleyes:

HPIM1769s.jpg


HPIM1750s.jpg


HPIM1798s.jpg
 
DLF, that is really close. Are there any clearance issues?

Nope, the engine rotates away from the shaft when I put my foot in it. :cool:

Remember, that is my SC, not my LSC. ;)
 
Thanks Doug. So what is the purpose of the telescoping joint in the OEM configuration? I guess I'm trying to figure out what effect losing it has on things. Crash protection? And back to one of my earlier questions: can you use a 3/4" DD shaft instead of the splined shaft?

Finally, assuming money is no object, can the FR vibration resistor joint be used instead? I don't see any dimensions, so I don't know if size is an issue.
 
Thanks Doug. So what is the purpose of the telescoping joint in the OEM configuration? I guess I'm trying to figure out what effect losing it has on things. Crash protection? And back to one of my earlier questions: can you use a 3/4" DD shaft instead of the splined shaft?

Finally, assuming money is no object, can the FR vibration resistor joint be used instead? I don't see any dimensions, so I don't know if size is an issue.

I would guess that the telescoping joint allows for ease of installation and accomodates production variances. Crash protection is accomplished by the breakaway joint at the top end of the upper shaft under the dash.

You need to use 3/4" splined shaft to connect to the steering rack stub. If you used DD shaft instead, then you'd need a DD to spline adapter at the rack, why bother?

You could probably use the joint that you linked, but again, why bother? I don't get any unwanted vibes using a solid joint.
 
Yeah, I posted too soon. I thought they had couplers with DD on one end and splined on the other but they don't.

So let me get all this straight... The car has one rag joint and we're replacing it with a U-joint. Basic geometry says two lines (the shafts) intersect at a specific point. Since we can't alter either shaft's angle, the U-joint is going to be in the exact same place as the old rag joint. So what's the point of doing this? I understand we need a smaller diameter to clear headers, but we're talking about manifolds here. In the pic of Jeremi's install, the U-joint comes nowhere near to touching the manifold.
 
The ONLY issue I have with the solid joint, is that I can hear the hydraulic system through the steering wheel.

Once the new exhaust goes on.....it may not be an issue.
 
No, The new joint is closer to the firewall with this mod. The column attaches to the rack with the 36 spline sleeve coupler.
 
So let me get all this straight... The car has one rag joint and we're replacing it with a U-joint. Basic geometry says two lines (the shafts) intersect at a specific point. Since we can't alter either shaft's angle, the U-joint is going to be in the exact same place as the old rag joint. So what's the point of doing this? I understand we need a smaller diameter to clear headers, but we're talking about manifolds here. In the pic of Jeremi's install, the U-joint comes nowhere near to touching the manifold.

On this new shaft, the "rag joint" isn't in the same place. It's moved up along the line of the steering rack stub about 8". That would change the angle of the upper shaft coming through the firewall.

Please bear in mind that I have never done this, so it's all just an intellectual exercise for me. ;)
 
In order for the joint to move, you have to be altering the angle of either the shaft coming out of the rack or the one from the steering column. I'm guessing the column, as you don't want to have the one going into the rack cockeyed, however slight.
 
In order for the joint to move, you have to be altering the angle of either the shaft coming out of the rack or the one from the steering column. I'm guessing the column, as you don't want to have the one going into the rack cockeyed, however slight.

your altering the shaft from the column to the rack. We tried using just the flaming rivers joint on the rack side, with no luck. Removing the short piece of shaft from the column and putting the fr joint on that location moves the shaft up which alters your angle and gives you the clearance that you need. You need the splined shaft and coupler to then connect the fr joint/steering column to the stub on the rack.
 
Just in case anyone is wondering why I modified my steering shaft, it was to gain a bit of header clearance on my SC (3rd pic). And yes, the Thunderbird and Mark VIII steering shafts are the same. :rolleyes:

DLF, a quick question for you. In viewing pic 3 with the headers on your T-Bird, and would assume the same goes for the Mark, would it not been easier to just notch the header tube at that very location? I keep picturing taking that header tube and cut a notch out, flip the notched out piece and weld it in. The amount needed for clearance would not be sufficient enough to disturb flow.

Just a thought on all this, I know it has no relevance to manifold swap but to header only swap.

Thanks
 
DLF, a quick question for you. In viewing pic 3 with the headers on your T-Bird, and would assume the same goes for the Mark, would it not been easier to just notch the header tube at that very location? I keep picturing taking that header tube and cut a notch out, flip the notched out piece and weld it in. The amount needed for clearance would not be sufficient enough to disturb flow.

Just a thought on all this, I know it has no relevance to manifold swap but to header only swap.

Thanks

Mess with a brand new $800 set of stainless steel headers vs. a little cutting and welding on the shaft? :eek::confused:
 
Some had asked about the size of the 99 vs 03 cobra. my 99 manifolds are a few hours away but I have my 03's and a 93 stock Mark VIII here at the house.
The 93's look close to the same size but choke down quickly in the port, 03's are straight through; if I remember correctly the 99's look better that the stock Mark VIII but do choke down more you follow the port through to the outlet.
I measured width and length of the 93 then 03. 93 is on the left in the picture.

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Some had asked about the size of the 99 vs 03 cobra. my 99 manifolds are a few hours away but I have my 03's and a 93 stock Mark VIII here at the house.
The 93's look close to the same size but choke down quickly in the port, 03's are straight through; if I remember correctly the 99's look better that the stock Mark VIII but do choke down more you follow the port through to the outlet.
I measured width and length of the 93 then 03. 93 is on the left in the picture.

Thanks!
I do have a set of 99's in the garage, I can measure them and compare them to the 03's.
I think we need to get together so we can see how much, and were the 99's choke down in the port compared to the terminators.

Food for thought, do you think it is worth port matching the manifolds to the b heads when installing?
 
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