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03 Cast Iron Block Swap with 97 Aluminum Block

  • Thread starter Thread starter Tim Harden
  • Start date Start date May 14, 2006
T

Tim Harden

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  • May 14, 2006
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Has anyone swapped an 03/04 cobra cast iron block out with an older 97/98 cobra aluminum block? Can it be done? Will the rotating assembly from the cast iron block work in the aluminum block? What all needs changed to make this swap work. Does anyone know of a posting that lists the pros and cons to making this swap and or details on what is involved in doing this.
 

Gearbanger 101

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First question....why? Second question....why?
 
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Tim Harden

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because the cast iron block I have has 2 broken ears on it from an accident and I have an aluminum block out of a 97
 

Gearbanger 101

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Fair enough....in that case....maybe. The parts themselves are probably a direct swap, but that doesn't guarantee that they're within tolerance. The only way to know for sure is to measure them with the pistons in the cylinders.
 

tomustang

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tig weld
 
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Tim Harden

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Took the block to 2 different professional weld shops to have the ears welded back on and they both said the one side is cracked to close to the freeze plug port so they both said it would most likely crack into the freeze plug hole, so the motor should be completely torn down the block heated then welded, so I figured why bother welding it if I could just swith blocks, and lose weight doing so too
 

tomustang

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Tim Harden said:
so I figured why bother welding it if I could just swith blocks, and lose weight doing so too
Click to expand...
you're gaining more weight, you getting rid of the aluminum block to put in a iorn block, plus the forged rods, and pistons
 

Mustang5L5

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tomustang said:
you're gaining more weight, you getting rid of the aluminum block to put in a iorn block, plus the forged rods, and pistons
Click to expand...

I think he's going the other way. He has an 03/04 cobra engine and wants to use a 96-01 teksid (sp?) aluminum block.

There is a reason why Ford changed from aluminum to the cast iron block for the Cobras. The reliability limits of the AL block are almost reached just with stock HP levels of the 03+ Cobra. Add a pulley and some more boost and you really will need a cast block, which is why Ford engineers swapped back to it.

Not a bad idea, but i don't think it's a good gamble
 

DropTopPony

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Mustang5L5 said:
I think he's going the other way. He has an 03/04 cobra engine and wants to use a 96-01 teksid (sp?) aluminum block.

There is a reason why Ford changed from aluminum to the cast iron block for the Cobras. The reliability limits of the AL block are almost reached just with stock HP levels of the 03+ Cobra. Add a pulley and some more boost and you really will need a cast block, which is why Ford engineers swapped back to it.

Not a bad idea, but i don't think it's a good gamble
Click to expand...
Thats absolutely not correct.
The Teksid block is good for 1000HP or more!
Ford switched to iron because of cost from most of the info i read.
 
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Stang2003GT

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Even if the stock aluminum block can only withstand the stock 390hp you could always sleeve the block.

Suprised anyone hasnt said that.
 

Mustang5L5

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DropTopPony said:
Thats absolutely not correct.
The Teksid block is good for 1000HP or more!
Ford switched to iron because of cost from most of the info i read.
Click to expand...

Ok then, i stand corrected
 

DropTopPony

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Mustang5L5 said:
Ok then, i stand corrected
Click to expand...

i didn't try to come off as an ass...hope it didn't seam that way.
 

tomustang

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Mustang5L5 said:
I think he's going the other way. He has an 03/04 cobra engine and wants to use a 96-01 teksid (sp?) aluminum block.
Click to expand...



And what Bob said
 

tontot77

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#14
  • May 16, 2006
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yeah, the aluminium is a great block for insane hp and Ford gave the 03/04 iron blocks was only because of cost... Using the old block is a good idea, but you might be going into uncharted territory... which most of the time produces headaches from unforeseen problems... If you do it, take some pictures of the process.

P.S. If you happen to get a scale out sometime, could you please tell me the difference in the blocks weight's?
 

Gearbanger 101

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tomustang said:
you're gaining more weight, you getting rid of the aluminum block to put in a iorn block, plus the forged rods, and pistons
Click to expand...
.....now which one of us is on glue?
 
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Tim Harden

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  • May 17, 2006
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Yes I was and still am thinking about swithing the 03 cast iron blockout for the aluminum, but still undecided. And in regards to the reliability of the aluminum I've heard it is good for 1000 hp and that ford did switch to the cast iron because of costs but heres my thoughts on that. Cast iron is going for $7 per 100 pounds and aluminum is going for around $60 per 100 pounds but the block before machining cant weigh more than 300 pounds so your only talking about $160 difference but with the aluminum there is alot more costs in machining because the aluminum has sleeves in it which could cost a few hundred more, therefore the total savings could be around $600 per motor make you wonder??? On the other hand I did read somthing about ford testing the supercharged cobra with an aluminum block and they kept cracking. Still not sure what I'm doing with it but if I do make the swap I'll posts some details.
 

Gearbanger 101

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  • May 17, 2006
  • #17
Tim Harden said:
On the other hand I did read somthing about ford testing the supercharged cobra with an aluminum block and they kept cracking. Still not sure what I'm doing with it but if I do make the swap I'll posts some details.
Click to expand...
Ford used a different aluminum block on the '99-'01 Cobra than they did on the '96-'98 Models and '93-'98 Mark VIII's. The earlier Mustang and Lincoln blocks were manufactured by Teksid (the same company that builds engine blocks for Ferrari) and are much stronger than the later aluminum versions.

Although the later aluminum blocks aren't as strong, they're still more than strong enough for all but the most serious horsepower applications. I wouldn't give strength issue a second though, if I were you.
 

Mike97gt

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  • May 18, 2006
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Mustang5L5 said:
I think he's going the other way. He has an 03/04 cobra engine and wants to use a 96-01 teksid (sp?) aluminum block.

There is a reason why Ford changed from aluminum to the cast iron block for the Cobras. The reliability limits of the AL block are almost reached just with stock HP levels of the 03+ Cobra. Add a pulley and some more boost and you really will need a cast block, which is why Ford engineers swapped back to it.

Not a bad idea, but i don't think it's a good gamble
Click to expand...


A ford rep tryied to feed me the same load of crap when the cobra first came out.
 

DropTopPony

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  • May 18, 2006
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Tim Harden said:
Yes I was and still am thinking about swithing the 03 cast iron blockout for the aluminum, but still undecided. And in regards to the reliability of the aluminum I've heard it is good for 1000 hp and that ford did switch to the cast iron because of costs but heres my thoughts on that. Cast iron is going for $7 per 100 pounds and aluminum is going for around $60 per 100 pounds but the block before machining cant weigh more than 300 pounds so your only talking about $160 difference but with the aluminum there is alot more costs in machining because the aluminum has sleeves in it which could cost a few hundred more, therefore the total savings could be around $600 per motor make you wonder??? On the other hand I did read somthing about ford testing the supercharged cobra with an aluminum block and they kept cracking. Still not sure what I'm doing with it but if I do make the swap I'll posts some details.
Click to expand...
Its about a $1,000 dollar savings for Ford to drop the Aluminum Block and use the Iron...it doesn't sound like alot but considering the 03 Cobra was already the most expensive Mustang ever sold at that time they had to cut costs somewhere. $35,000 was alot for people to swallow...but we all know that those cars are worth every penny once you own it.
 

mogs01gt

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Tim Harden said:
Yes I was and still am thinking about swithing the 03 cast iron blockout for the aluminum, but still undecided. And in regards to the reliability of the aluminum I've heard it is good for 1000 hp and that ford did switch to the cast iron because of costs but heres my thoughts on that. Cast iron is going for $7 per 100 pounds and aluminum is going for around $60 per 100 pounds but the block before machining cant weigh more than 300 pounds so your only talking about $160 difference but with the aluminum there is alot more costs in machining because the aluminum has sleeves in it which could cost a few hundred more, therefore the total savings could be around $600 per motor make you wonder??? On the other hand I did read somthing about ford testing the supercharged cobra with an aluminum block and they kept cracking. Still not sure what I'm doing with it but if I do make the swap I'll posts some details.
Click to expand...
You wont have to resleeve the block if you arent going over a .020 bore. The machining costs on my alum. block were a standard price compared to a iron block.
 
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