lol it took me a while to realize what you were trying to say and then I thought "Oh, he must have meant 'street value'."
In 96 the cars got a 5 HP increase but I don't know if that's because of heads, intake, cam, engine or computer. The intake manifold has a different bolt pattern than 95 & lower, but I don't know if there's any internal changes (i.e. runner length/size). I don't think that those manifold are by any means rare so I would think the value would be maybe $75-$125.
As far as I know the increase in power on the 96 and 97's was primarily attributed to the exhaust manifold change.
Very good point. I forgot about that, even though I have those "new" manifolds.
Edit: I've been thinking, and I'm wondering if anyone knows why Ford even changed the heads/intake to accept fewer and smaller bolts. I'm talking about the intake manifold-to-head bolts. Was there any particular reason?
I've ported several sets and IMO the Pre-96 lowers are better then the 96-98 lower intakes. The 96-98's I've done seem to suffer from core shift alot and leave nasty casting flash in the runners that require alot more work to smooth the flow.