Want to swap a 03-04 Svt Cobra motor into my 69 Mach 1

[montys69mach]

Hello there everyone!! I am new to this forum and not sure if this swap has been dicussed before. I am a previous owner of a 69 Sportroof, with a 71 Boss motor (351C 4V), and a 70 Mach 1. I just recently purchased another Mustang. I found a nice original 69 Mach 1. Its a windsor 2V with a FMX. I plan to take the original drvetrain out and wrap it, in case I want to put it back to original. Lets face it, you can make tons of power with a new cobra motor. Has anyone performed this swap, or can you give me some information on how I can get things started? I want to go with a T-56 as well. I have a 9" with 3.00's (stock). I plan to go with 55's or 73's. With the 6 speed do you think 4.11s would be too much for daily weekend driving? Thanks in advance for your help and advice.

Anthony

 

[Route666]

You can see from http://home.att.net/~marksmoore/Weights.htm that even the aluminium blocked DOHC weighs as much as a 351W, and by the looks of it, (compared to 302 with aluminium heads) that is with iron heads.

The shock towers need a little massaging to get the motor to just fit, it is apparently 1" wider than a BOSS 429.

You can get parts for 302s and 351s pretty cheap these days, so combined with lighter weight, especially with alloy heads, and less modification required to the car to get it to fit, it isn't that smashing of an idea. It's been done before, several time, so it's not really an original idea either.

If you want to do something a little special, get an aluminium 351 block, with a 408 stroker kit and a supercharger. It'll probably cost slightly more than a mod motor, be easier to put in, and most likely give a much better power to weight ratio, even if it didn't weigh less.

So that's my opinion, I've looked at the swap, to find out the same things you wanted to know, and found that just for DOHC it isn't really worth it. You can stick fuel injection and superchargers on a Windsor.

 

[3spd on floor]

If you put an 03 cobra motor in a 69, you can never go back to original. It requires cutting up a lot of metal. i believe fostang is putting a DOHC 4.6 in one of his mustangs, he can tell you more about the swap. i wouldnt cut up a "nice original" mach 1, but its your car and you can do what you please with it.

 

[DarkBuddha]

I'm not aware of any finished versions of this swap in a '69 or '70, but it's probably been/being done. By all accounts, it will require some shocktower modifications at a minimum. This means the car won't ever be completely "stock" again, but you would be able to eventually swap the original drivetrain back in again if you wanted.

Ultimately, we have discussed these types of swaps occasionally when one of us gets the bright idea and a good deal on a donor car. But as Route666 mentioned, if you do the math, you can get comparable performance/efficiency from a properly built pushrod motor for the same or less money and no shocktower modifications. However, I figure if you've got the coin and time and the skill, I say go for it and let us know how it turns out.

Good luck.

 

[Route666]

I believe with the 69 and 70 bodies you only have to ummm "persuade" the towers out a little in the lower regions. Because the 429 just fit, and this is a little bigger, it just needs tweaking.

I didn't mean to sound like a downer either, sorry if it came across like that. If you want to do it, go for it. I used to like the idea, but now my heart flutters more at the thought of the most advanced of the original type components. I'm also an efficiency maniac, efficiency of every quality, not fuel. Weight is a big one, less weight accelerates faster, takes less fuel to push around, and brakes and turns better.

Anyways, enough blabbering. I should have told you about www.dvsrestorations.com in my first post too. Good place to start looking at this swap.

 

[DarkBuddha]

I believe with the 69 and 70 bodies you only have to ummm "persuade" the towers out a little in the lower regions. Because the 429 just fit, and this is a little bigger, it just needs tweaking.

Just a reminder, but the Boss 429s used special shocktowers that were smaller than stock Mustang shocktowers. The cars were shipped to and modified by KarKraft with shorter upper a-arms and smaller shocktowers. That is the only way the Boss 429 motor would fit.

So, as I said before, I still believe you'd need to modify the stock shocktowers to make the DOHC Cobra motor fit.

 

[87gn2]

#1 Unless you get a great deal on a junkyard engine, a new Cobra motor will cost you close to 10 grand.

#2 There are many small block turbo/supercharged Mustangs putting out well over the paltry 800hp the Cobra is currently at (with a KB 2.4 supercharger, that is), with 150lbs less weight.

#3 I hope you like working in tight spaces...

4.11s with a 6 speed should be fine.

 

[Route666]

Just a reminder, but the Boss 429s used special shocktowers that were smaller than stock Mustang shocktowers. The cars were shipped to and modified by KarKraft with shorter upper a-arms and smaller shocktowers. That is the only way the Boss 429 motor would fit.

So, as I said before, I still believe you'd need to modify the stock shocktowers to make the DOHC Cobra motor fit.

Oh yes true true, so there would be some rather drastic modding needed.

 

[montys69mach]

Thanks for the advice. My only concern was if the cobra motor would fit without cutting the shock towers. I'm not into choppin up an original mach, that is fully functional. With that said I will most likely be looking for a complete stroker motor stroked to 408-427ci. I will consider forced induction probably a turbo. I'm not sure if your fimilar with Greg Smiths Mustang from JBA racing, it was seen in Hot Rod and on Speed, it sports a turbo'd 408 with a T-56. Looked like a nice combo, but after inquiring about the set-up, I didn't think it was worth the 25 grand. Would you recommend buying a crate stroker motor or have one built from a shop? If you suggest buying a crate motor where do you suggest I get it from? Thanks again for all your help.

 

[3spd on floor]

ok, we are talking about making TONS of power, so i have to ask what kind of experiance you have with cars of this degree? also what are you wanting to do with the car?

if you build a boosted 408w you can easily make well upwards of 700hp. now your problem will be getting that power to the ground, and i think you'll find that this will be a hard task to accomplish without "cutting up" or permanently modifying at least a few things.

 

[StangDreamin']

#1 Unless you get a great deal on a junkyard engine, a new Cobra motor will cost you close to 10 grand.

#2 There are many small block turbo/supercharged Mustangs putting out well over the paltry 800hp the Cobra is currently at (with a KB 2.4 supercharger, that is), with 150lbs less weight.

#3 I hope you like working in tight spaces...

4.11s with a 6 speed should be fine.

Hey Andrew!!!! Long time no hear- from!