Ford Mustang Forums banner

1 - 5 of 5 Posts

·
Registered
Joined
·
401 Posts
Discussion Starter #1
Not sure if they are tremendously better for performance or not? Was going to ask for some opinions?

Is the compression go way down on a 4.6?
Are these Tumble ports? ...
and would I have to run a newer intake (99+)?

OR should I keep my current heads and port them? Want a stock look (car is Mystic).

Thanks!
 

·
Registered
Joined
·
776 Posts
Navi Heads

I have a set that are Extrude Honed. They are tumble port like 99 Cobra heads, compression is the same, and the intake ports are larger than the 4.6L Cobra heads. You can use a 99-up Cobra intake "ONLY" if you hog out the ports to match the larger intake ports on the heads. Get with Educan911 for pictures of his custom ported intake to fit those heads. -John

Edit - not sure but Boss330 might have did this custom intake.
 

·
Registered
Joined
·
174 Posts
NX,

Thanks for the reply. Are the heads on the car yet. If so what kind of power are they making. Of course if you had before and after #s that would be great.

Thanks
 

·
Registered
Joined
·
776 Posts
Educan911 might be able to get you dyno numbers, but he is ProCharged. Not sure if he is runing the same boost to compare HP increase either. My 5.4L Navi heads are for my 5.4L DOHC project im swapping in my 97 GT. It will be mid-summer before it's complete because im going to college full time and can't get to it at the moment. -John

ps I have pictures of the heads if you want to see, so pm your e mail.
 
1 - 5 of 5 Posts
Top