The ported PI heads are more than a match for the SVO heads. Even if you port the SVO heads you can put a bigger exhaust valve into the PI heads. SVO engineers moved the intake valve away from the chamber wall to unshroud it. This severely limits the size of the exhaust valve. In fact, the SVO exhaust valve is the same size as the stock '96-98 valve. The PI heads will accept much larger valves. The ModMax oversize stainless steel valves along with some well executed porting will allow the PI heads to run over the SVO units.
Next you run into the problem of compression ratio. The PI heads (in stock form) will bump the compression of the '96-98 engines to 10.5:1. Not good for boost! With a few hours spent modifying the combustion chambers I can lower the compression ratio to a more boost-friendly 9.25:1 compression. If you do this mod and remain normally aspirated you will lose some of the added horsepower you would have gained but you will still have a very tough street engine on your hands. Better ports, better cams, larger exhaust valve.
In my honest opinion, the PI heads are a much better "bang for the buck" deal than the SVO heads. Also, the Bullitt intake can be had fully ported and ready to bolt on for $1500. The new pricing on the SVO Hi-Flow Intake from Ford is over $1600 and that doesn't include the installation kit.
For your car I would do the following:
Ported PI Headswap Kit
Headers (shorties are easy, longtubes make more power)
DTA Regrind cams or Crane regrind cams (the SHM cams suck......the stock PI cams feature more lift)
3.73 or 4.10 gears
Stock throttle body, MAF, injectors
Aftermarket H-Pipe with cats (H pipe works better for torque on these engines than the X pipe does)
Three chamber Flowmaster Delta Force mufflers (no 2700 rpm drone)
The SHM cams will kill low and mid range power and throttle response due to the large duration number on the intake side along with the wide centerline. You want cams with good lift numbers (.540-.550) with intake duration no larger than 222 degrees at .050" lift. Lobe seperation angle of 110 or 112 degrees.
The parts you listed will make OK power. They'll also cost you an arm, leg and one testicle. With the PI power combo I listed above you can run rampant over an SVO-equipped car for less than half the money. The headswap kit is $1500 (or $1300 without the intake) and the Bullitt kit is $1500. So, for less than the price of the SVO heads, fully equipped, you can have a complete top end package that will put you into the high 12's with good tires and driving. Plus, I can tailor it to work with a blower if you want to do that in the future. Add a blower to this combo and you're a mid-11 second player. You don't have to mortgage the house to go fast. You damn sure don't have to rely on FRPP or SHM. Let me know if I can answer any questions you may have.
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