Chevy & GMC Vans

I am thinking of rebuilding the v-6 that came out of debbies van. I wanted to find out some info on having the heads and intake ported. Such as,are their any certain specs, will I have to change the fuel system in any way, should i change the valve train and can I use the stock tbi. I could also use any info on cams. Can I put a bigger one in a v-6. Thanks for your support, and we'll leave the light on for ya.
Dennis

-if it's a Vortec (96+) van don't port the heads or have it done. High flow valves maybe, mods below for high lift and a new cam and go.
-If it's a "W" motor (92-95) having the heads ported will probably be worth it. The cam is nice leave it be.
-If it's a "Z" motor or "B" motor from 86-91 the heads are pretty lousy. Try to find a set of CPI (92-95 W VIN) heads if possible, even stock for stock they'll do you better and they're a bolt on swap. Also cam up. The old cam is heavily emissions oriented in the "Z" motors and even in the "B" motors less so but it's still a pretty tame grind.
-valvetrain work on your heads should include a new set of springs, such as the Comp 981 springs or a set of Competition Products "Z28" springs. If you keep a stocker cam go with the Z28 springs, if not the Comps provided you don't get springs with the cam. Further work will be dependent on your cam's lift and RPM range. Best to talk it over with your machinist.
-I'd probably forget having the TBI intake worked on short of a basic port matching or machining the bores for a larger TBI unit. It's just too easy to rack up machine shop $s that could very well be spent on an aftermarket intake that'll flow as well if not better and be at a better power band. Don't forget you can use a carb intake with an adapter too.
-fuel system wise it depends on the vehicle. If the vehicle has a MAF it will be a lot more tolerable to the mods done without any reprogramming. I know the 96+ Vortecs are MAF and I'm wanting to say that 92-95 vans were speed density, while all the TBI vans were speed density. This means at the very least you'll need an adjustable Fuel Pressure regualtor and a fuel pressure gauge, which isn't difficult to make or not overly expensive to buy. Another option I'd strongly consider is talking to the fellow that runs tbichips.com and having a custom chip cut based on your cam/heads/intake, or even talk to him beforehand to get a reccomendation on the cam selection to make it easier to tune. Adjustments of fuel pressure will help with the increased flow, however your'll probably still not be anywhere near as optimal as a good chip will allow you.