I am so confused, a 3.9 is a ....?

[jjtbird]

I read a post recently that said the 02 through 04 engine is a variation of the Jaguar 4.0 used in the Lincoln LS as a 3.9, however the 2005 is not the same base engine but rather a de-stroked 4.7 ? My friend has a 2005 and I have had a 4.7 in the past but to me they just dont look related to me.

Just curious.
Thanks

This page contains affiliate links for which I may be compensated. As an eBay Partner, and Amazon Associate I may be compensated if you make a purchase at no cost to you.

 

[PhilD]

I have an 02 and yes its basically a jaguar XK engine and transmission with a lincoln ls body base. Don't know about the 05's unfortunately as I don't have one so just concentrate on what I need to know.

 

[frank1353]

I read a post recently that said the 02 through 04 engine is a variation of the Jaguar 4.0 used in the Lincoln LS as a 3.9, however the 2005 is not the same base engine but rather a de-stroked 4.7 ? My friend has a 2005 and I have had a 4.7 in the past but to me they just dont look related to me.

Just curious.
Thanks

The 2002 3.9 engine does not have variable cam.
The 2003-2005 Tbird and 2003-2006 Lincoln ls is the same. The Jaguar 4.0 is only one mm more on the bore and has the boss for the Supercharger. I think the heads are a bit different also.

 

[Quickdraw]

Frank1353 knows his onions.. he is even correct about the heads too....

 

[captrick]

The 2002 3.9 engine does not have variable cam.
The 2003-2005 Tbird and 2003-2006 Lincoln ls is the same. The Jaguar 4.0 is only one mm more on the bore and has the boss for the Supercharger. I think the heads are a bit different also.

The 2002 3.9 engine does not have variable cam.
The 2003-2005 Tbird and 2003-2006 Lincoln ls is the same. The Jaguar 4.0 is only one mm more on the bore and has the boss for the Supercharger. I think the heads are a bit different also.

Frank1353 knows his onions.. he is even correct about the heads too....

The 2002, 03, 04 are all rated at a lower HP due to the cam timing and the intake manifold. The 2005 is a few HP higher due to variable cam timing and an intake manifold that is very much like the 2004 Cobra motor. The difference in the manifolds are the 02, 03, 04, all have the air intake in the back of the manifold, in 05 the air intake is in the front of the manifold and has a different layout of the runners. The 3.9 liter and the 4.0 liter Jaguar motor are the same motor. The transmissions and other parts are all interchangeable. Back in 2005 Ford still owned Jaguar and was trying to make the brand more dependable and bring up sales of the company so they used the modular V8 design which has been proven very dependable since 1996.
You can take a 4.0 liter Jaguar motor which is Supercharged and rated @ 430 hp and it will bolt into the T - Bird. I have taken my 2005 T - Bird and installed a tune to the computer and picked up 2 more miles per gallon on the Highway and got better performance out of it. Experts have told me with that tune the motor is probably rated just over 300 hp. I hope that this helps to clear up any confusion that one may have.

 

[clyde]

Will the AJ89909. Harmonic balancer bolt will fit the 3.9

 

[Pcrpete]

The 2002, 03, 04 are all rated at a lower HP due to the cam timing and the intake manifold. The 2005 is a few HP higher due to variable cam timing and an intake manifold that is very much like the 2004 Cobra motor. The difference in the manifolds are the 02, 03, 04, all have the air intake in the back of the manifold, in 05 the air intake is in the front of the manifold and has a different layout of the runners. The 3.9 liter and the 4.0 liter Jaguar motor are the same motor. The transmissions and other parts are all interchangeable. Back in 2005 Ford still owned Jaguar and was trying to make the brand more dependable and bring up sales of the company so they used the modular V8 design which has been proven very dependable since 1996.
You can take a 4.0 liter Jaguar motor which is Supercharged and rated @ 430 hp and it will bolt into the T - Bird. I have taken my 2005 T - Bird and installed a tune to the computer and picked up 2 more miles per gallon on the Highway and got better performance out of it. Experts have told me with that tune the motor is probably rated just over 300 hp. I hope that this helps to clear up any confusion that one may have.

Hi Cap
Can you publish what that tune is that you programmed?
Thanks

 

[sscharfman]

The 2002, 03, 04 are all rated at a lower HP due to the cam timing and the intake manifold. The 2005 is a few HP higher due to variable cam timing and an intake manifold that is very much like the 2004 Cobra motor. The difference in the manifolds are the 02, 03, 04, all have the air intake in the back of the manifold, in 05 the air intake is in the front of the manifold and has a different layout of the runners. The 3.9 liter and the 4.0 liter Jaguar motor are the same motor. The transmissions and other parts are all interchangeable. Back in 2005 Ford still owned Jaguar and was trying to make the brand more dependable and bring up sales of the company so they used the modular V8 design which has been proven very dependable since 1996.
You can take a 4.0 liter Jaguar motor which is Supercharged and rated @ 430 hp and it will bolt into the T - Bird. I have taken my 2005 T - Bird and installed a tune to the computer and picked up 2 more miles per gallon on the Highway and got better performance out of it. Experts have told me with that tune the motor is probably rated just over 300 hp. I hope that this helps to clear up any confusion that one may have.

What tune did you have done?

 

[clyde]

Will the jag 4.0 harmonic balancer bolt AJ89909 fit the 3.9, i am in desperate need of this information.