BA 5.4 V8 - 4 Valve head vs 3 Valve Head - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

jas · 11-17-2005, 01:48

Hi,
Can anyone tell me if the exhaust ports and manifold bolting pattern are the same from the 4 valve head to the 3 Valve head?

I have a 3 Valve V8, and have been given a set of 4 into 2 into 1 extractors off a GT-P, and am curious as to whether they would fit.

outback_ute · 11-19-2005, 13:08

I can't tell you for sure jas, but I doubt it. Can you see the bolt pattern on your heads?

assasinator · 11-24-2005, 14:21

they are not the same. although they are similar. "b" ports on 4v's are thicker and not as long, but they have higher volume than 3v. the exhaust ports are totally different. spacing is the same, but size is different. 4v exhaust ports are wider. bolt pattern for 4v and 3v is different also. 4v bolts are at an angle, 3v bolt pattern is straight up and down.