Vanir Tech. is a great site for the 4.0, or should I say use to be a great site for the 4.0. I know Sven Pruett, owner and operator of Vanir, and he has all but completly shut off the public side of their operation. They still have a few things on their page but if you'll notice alof of stuff is missing.
Now not to endorse my own site or advertise, please let me know if I'm over stepping my bounds here guys, but I'm in developement of my own 4.0 internet business. I have over 9 years of experience working with, on, and modifiing not only the OHV 4.0 but the SOHC as well. In order to keep the peace I won't post the URL of the site but its coming along nicely.
As for the parts you listed here's my take on that.....
I have the roller rockers, they suck!! I've sold 4 sets of these and every set I've had to send back and even then when I got them back they had to be modified to make them work properly. For the $400 your gonna pay for them you can get a set of reworked stock rocker arms with hardened tips for about $150 less that will bolt directly on.
The camshaft is really a application type deal. If your gonna drive it every day and are just looking for improved torque through out the RPM's range and not looking to have a chip then go with the Comp Cams 49-410-8 or as I call it the 410 cam. Now if your looking for an all out performance camshaft and also plan on having a custom chip made then the 49-422-8 or 422 cam is a good selection. The main thing with it is is requires a bit more computer modification, not to mention it doesn't idle as well.
Now both of these camshafts require longer pushrods so you'll need to contact Smithbros. pushrods to get these, they're around $75-$95 depending on what grade you select. I like to use them because they've done alot of work with Sven on the 4.0 pushrods and know what your looking for rather then just some pushrod company.
Also don't forget that with the 410 cam you may get away with using the stock valve springs for a little while but you'll really need to upgrade to dual springs. With the 422 it's a requirement.
Porting a polishing is a great improvement for the 4.0 on the cylinder head but you really need to address the lower intake first. This is one of the great bottle necks of the 4.0. If you do port the heads on the pre-98's don't remove the exhaust bumps in the ports, you'll find holes underneatht them
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Most importantly for anyone, don't overlook the basics first. If your wanna do a camshaft or port work then make sure your engine can use it. Do all the bolt on's first, mass-air, TB, headers, free flowing exhaust, you know the basics. Then address the internal components. Also you'll need to address the condition of your engine. If you have 170,000 miles on your 4.0 then its probably not too benificial to install freshly worked heads or new camshaft only to blow out your rings. Think before you mod!! haha, Later Doug904.
