[squid]

If you already have the longtubes then stick them on. The point I was trying to get across is that you should match your purchases to the combination you are going to have for a decent amount of time. If you put long tubes on an engine with stock type heads your only going to see an increase in horsepower just before the heads give up in rpm. Stock type heads would need some serious porting to utilize the power potential of long tubes. If you know your goint to slap on a set of high flowing heads in the "near" future then you have exactly what you need in long tubes. The factory headers even though they seem very restrictive are not one of the bigger gains in horsepower or torque to replace when your early on in your mods.
If your going to stick with your longtubes then have that explorer intake ported, the gt40 heads really ported especially on the exhaust side , better valve springs,(or get some already done like thumper heads) slap in a custom cam, bigger meter and hang on. I hope some of this helps.