Engine Looking for advice on a cobra swap into a gt

Hi everyone, I have a 2002 mustang gt with a manual trans, fairly stock except some new suspension, cai, and mufflers I've put on it.

Anyway, I've got a friend willing to sell me a 97 Cobra engine that's been bored to 289 and has a rebuilt bottom end that I plan to swap into my mustang. I'm just curious on things to watch out for, like whether or not I'll need to build my transmission or need a new hood, things like that. I figure the harness and ecu from the 2v won't work with it, and since the older sn95's used an analogue gauge cluster (I think, or at least a different one than the 99-04's) I might have to change something there.

Any advice helps, thanks!

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I won’t say for sure (cause I don’t know) other than some sensor locations (may be in different spots) and one engine being coil on plug (02) and the other having coil packs/wires (97) it should be a direct swap.
Fairly certain you will have to retain the ‘02s intake and maybe accessory drive, possibly the exhaust manifolds (good time for headers) but a 4.6 is a 4.6 (right?)

Now with all that mostly useless stuff I said outta the way, my question is why ?

If that rebuilt motor is just a bored out ,stock style piston, stock crank and cams rebuild- I don’t know that it would be worth all the effort and expense for a barely noticeable power upgrade-unless your current motor is just plain ole wore out :shrug:

Also- Welcome to Stangnet
If it is an original 97 cobra engine - that would be a teksid aluminum block.... if you have the money and patience it is a great way to get the best / lightest 4.6 block. Your Ecu and the wiring harness (minor mods) will work.

here is a list of things to get started on:
New gaskets
Exhaust is different
The fuel lines are different
The oil pan is different
The oil pickup tube needs to be modified
The throttle cable and cruise cables are different
The radiator hoses are different
Your wiring harness will need to be taken apart and one side of the coil plugs lengthened
You will need to use some of your original vacuum lines and some from swap.

See here:

If it is a short block you’ll have to change out the pistons to 2v pistons and will have to eval the oil and coolant lines. Easy swap otherwise.
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Hey guys, thanks for the great input (and the warm welcome!). First to answer why I want to do the swap: the lightness of the aluminum block, and it's an extra 45 hp at least (or that's what I figure anyways). One of the long term goals for my car is to handle well, and I figure it's a good way to hit that 300 hp mark I want, and lose some of that cast iron v8 weight at the same time. At this point I'm still just toying with the idea, but if he gives me a good enough deal for it then I might consider it further. . .

Thanks again, Daniel

P.S. I should add that the ecu and wiring harness may be included
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This swap would be a little more straight forward than my 5.4 DOHC swap. The T3650 is good for about 400lbft of torque. Dark04GT mentioned that the oil pan, pickup tube, fuel lines and exhaust are all different. While this may be true, they should be direct bolt ins with any SN95 platform. The oil dipstick is in the same place as the 4.6 SOHC as well.

Depending on the pistons that your friend used for the overbore, the engine might make a bit more power than the stock 305hp. You can use the stock 2002 PCM, however it will need to be tuned, especially if the pistons increased the compression ratio. You might also have to run E85 or Premium fuel. Be aware that the 97 Cobra PCM will work, however PATS will throw a fit and will have to be disabled.