View Full Version : Head?'s

05-20-2003, 06:28 PM
Just curious if there is a difference in the heads between a SC 3.8 vs. a NA 3.8. ie cc size ect... also if anyone has tried using the mustang 99 up heads.
thanks, Steve

Duffy Floyd
05-20-2003, 06:42 PM
Yes the SC heads have redesigned water passages as well as increased boss area in the region of the head bolts for 2 changes I know of. Also to go to the split port.....what advantage would there be with a box plenum like is installed on the SC engine?

05-20-2003, 06:50 PM
so the 99 up heads are a different style?...im not very famiar with them but i am needing a set of heads. i dont want to get a set of NA heads and it ping etc.... due to the compression ratio being higher.

05-20-2003, 07:12 PM
To help identify, the SC heads are stamped "SC" in the corners of the heads. It would take some custom work to get the 99+ heads to work.

05-20-2003, 07:46 PM
I did the splitport swap in my 94 LX. To install the SC on these heads, you'd have to make an intake. The heads have two intake runners per cylinder, where as the singleports only have one per cylinder. I've attached a couple pics of a spare set of 99+ heads I have. The second pic is of the intake ports.