The DOHC gain a lot from porting. Racers have them done all the time.
The thing with the B heads is that the intake ports have so much volume it kills velocity. This makes for great high RPM air flow and HP,.. but kills it for lower RPM grunt. So unless your packing a 88mm turbo for that thing,. I would leave the stock porting alone. At most I would just remov the IMRC plates.

Here are some picks to help me show you the B head compared to the later C heads.

93 - 98 B heads.




And here is 03/04 Mach1 and Terminator heads.




Here are the head data charts. I scanned these from Sean Hyland's book also.





You see on the volume chart where the B heads have 107cc on the primary port and 115cc on the secondary port. Thats a TOTAL of 222cc intake port volume for a little 281ci engine. Thats like taking an AFR 225 head and slapping it on a 5.0. The 302 would need to spin to 7000 to make any HP and have nothing down low. A DOHC B headed motor has similar issues but not as badly matched as AFR225 on a 302. The 96 - 98 Cobra engines have no problem spinning to 7000 RPM (AND BEYOND). And thats why they keep pulling and are making good power all they way to their redline. If your a seat of the pants racer like me (dont really watch the tach) you'll hit the rev limiter every time between shifts on a B headed motor. Its incredible how that motor responds to RPM's.

But on the flip side,.. look at the flow chart. The B heads dont flow any better then the smaller port in the 03/04 Terminator heads. Dont let the chart fool you. DOHC cams dont have a lot of lift. They dont need it to make power. But,.. B heads do flow very well after porting. Turbo guys love B heads because they make gobs of HP at high RPM's and are arguably better at high RPMs then the 03/04 Terminator heads.

Sorry for the hijack AB,.. but you probably found that interesting also.

Hurst