T-Bird 4.6 SOHC to DOHC swap...

[clowe1243]

I am plaining to do a 4.6 SOHC to 4.6 DOHC (Cobra) swap in my t-bird. Not concerning with hood clearance, flywheel, or bellhousing...has anyone done this swap already or know of any literature that will help out? I'm great at fabrication and engineering, and have heard and seen this swap done in pictures, but do not know of the difficulty I will be getting my self into. What modifications will I have to get done to the motor / left powertrain of the car before I can begin this project? I'm told I can use a Mark VII harness? How long would it take to set that up if you've done this before?

Hey, If you know anybody that does a good job on this swap, let me know!

Chris

[olddog]

I was not aware the 4.6 ever went into the T-bird. What year T-bird? What is the Cobra out of (year and modle)?

Most likely ECU that originally ran the engine would be the no brainer approach. The Cobra has larger sized injectors. Depending of year, it may require a different fuel system. Mass air flow meter may be different.

[clowe1243]

Yes sir...the tbird came with the 4.6 from years 94-97? It was the considered option since the performance package was a superchargered 3.8. The Cobra engine is out of a 99 Cobra 4.6 DOHC w/ 5 speed.

What I was wondering was, how long and how would the tbird's wire harness change over? If it is too complicated the 5.4 SOHC would be the way I go since it just bolts in for the most part!

[olddog]

You never answered, which year the T-bird is.

1999 was the first year for the coil on plug technology. These are the years that they switched from the EEC-IV to the EEC-V. Different cars switched in different years. You are going to need some expert advise, and I'm no expert.

I don't like the 5.4 for a high performance engine. Too long a stroke for the bore in my opinion.

I would like to have the 99 cobra engine myself.

Good luck!

[olddog]

Oh by the way deck hieght on the 4.6 is 8.937 the 5.4 is 10.079. So the 5.4 engine is about 1.142" taller and wider. It may not fit as well as the 4.6 32v.