Yes it can be done I saw it in a magize. but I dont know how
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95/5.0 Long tube headers, xpipe, flowmasters, with dumps, 9mm plugg wires, msd cap and rotor, 70mm tb, trick flow intake manifold, under drive pullys, smog elim kit. summit coil, subframe connectors, summit double roller timing chain, and a cam not sure what for cam bc it was in the car when i purchesed it!
You will need a set of DOHC complete heads. I believe some of the accessories brackets have to be changed. A Cobra upper intake, TB, and intake from fender to TB. You can use your harness but it would be better to get a cobra harness and computer. Exhaust manifold/header.
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1998 GT Saleen replica
New forged internals w/cobra crank, TEA CNC ported heads w/ comp cams XE270AH, AccuFab throttlebody and plenum, Spec III clutch, TKO 600 trans, aluminum drive shaft, 3:73 gears, BBK long tube headers, 255lpm intank fuel pump, Dyno tuned, Polished Procharger D-1sc 12psi, 3 core intercooler. SVO hood and 18in Budnik wheels w/toyo tires. Caster/Camber plates BBK lowering springs. Car web page
Comp cams XE262AH,T-45 with tri-ax shifter for sale
It all matters on what kind of deals you can get. A set of cobra heads flow more then a set of ported PI 2v heads. If you can get a good deal on everything then I say its a good investment now and for later. I believe that their is a compression lose when do this cant say how much a point or so. How much power are you wanting and how much money you want to spend?
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1998 GT Saleen replica
New forged internals w/cobra crank, TEA CNC ported heads w/ comp cams XE270AH, AccuFab throttlebody and plenum, Spec III clutch, TKO 600 trans, aluminum drive shaft, 3:73 gears, BBK long tube headers, 255lpm intank fuel pump, Dyno tuned, Polished Procharger D-1sc 12psi, 3 core intercooler. SVO hood and 18in Budnik wheels w/toyo tires. Caster/Camber plates BBK lowering springs. Car web page
Comp cams XE262AH,T-45 with tri-ax shifter for sale
It all matters on what kind of deals you can get. A set of cobra heads flow more then a set of ported PI 2v heads. If you can get a good deal on everything then I say its a good investment now and for later. I believe that their is a compression lose when do this cant say how much a point or so. How much power are you wanting and how much money you want to spend?
4V heads on a stock PI shortblock= 8.5:1 compression
4V heads on a stock NPI shortblock= 9.1:1
As stated, look for a complete engine. I got a 99 C head engine for $800 complete. Deals are out there. Do realize that parts are much more expensive for a 4V, because they have twice hte number of valves. A bolt on 4V can make 340rwhp N/A easily.
4.6 SOHC conversion to DOHC 
