Shelby heads on a 4.6?

[pmot]

I am just curious to see how much something like this would cost, Im probably not interested in doing this swap. I have found shelby heads for $1600. I know that the heads will bolt up to the 4.6 but is there a intake manifold out there that would make it work? also what changes would have to be made to get it to wire up correctly.
Thanks for any help you can give me.

 

[Jrgunn5150]

Yep, any cobra intake

 

[DropTopPony]

What are you starting with?

If its a 2V you have lots of parts to find.

 

[Jrgunn5150]

Yep timing cover, chains, manifolds, throttle cable, tb, etc etc. Tuning blah blah blah. Shelby heads are the best though.

 

[DropTopPony]

Now what I am curious about is are they that much better then the 4V C heads that you would drop an extra $800 or so more for them on a street car?
I've seen C heads go for $500-800 so the money you save would be cams money or Intake etc.

The GT500 are the same as the GT heads aren't they?

 

[Jrgunn5150]

They are the same as GT heads, supposedly better thaan FR500 heads, worth twice the cost? Not unless you are pushing the envelope imo.

 

[pmot]

What are you starting with?

If its a 2V you have lots of parts to find.

It is a 98 cobra.

 

[pmot]

Now what I am curious about is are they that much better then the 4V C heads that you would drop an extra $800 or so more for them on a street car?
I've seen C heads go for $500-800 so the money you save would be cams money or Intake etc.

The GT500 are the same as the GT heads aren't they?

Your probably right it wouldn't be worth the money on a street car but Im still curious. they are the one of best heads you can get though. they flow about 275cfm @ .5 and the cobras only 230ish they also are far better designed.

 

[pmot]

Yep, any cobra intake

Are you sure? I have looked in a lot of places and most of the time i heard that the intake ports are different along with the bolts won't line up.

 

[DropTopPony]

So you have a B head 4V. Thats helps cut the cost some but I believe you still need a C head intake from a Cobra or Mach/Marauder etc.

 

[pmot]

I heard those intakes wont bolt up?

 

[pmot]

I think I found an answer to the intake manifold question.
I read this at http://www.sullivanperformance.com/yvs450/tech/tech1.htm
There are several different castings available for the DOHC heads. 4.6L & 5.4L heads will physically interchange, but the ports on the 5.4L heads are much bigger than the 4.6L heads. Neither the Cobra or Lincoln intake manifolds will work with this swap. If you were able to get the intake to bolt on, there still is not enough material around the ports to enable port matching to the larger navigator heads. Our single plane 4.6L intakes were designed with enough material to allow for this swap.

It is obvious that a 5.4 manifold would not fit but they also say 4.6 manifolds don't have enough material to make them work either. In that paragraph it didn't say anything about Mach/Marauder manifolds but it did say the cobra manifold would not work. I assume that the same applies or the Mach/Marauder manifold.

Now I am more curious about the 03 cobra head swap. Is there an article somewhere that explains it step by step?