Ok, as posted previously I will be installing an Air-Gap intake and 600 Performer carb on my 360 (actually should have been done by now, but chit happens). Well, now I'm thinking that since I'm going to have the top of the engine apart and I have a lifter knocking when cold, why not go ahead and do a cam/lifter/timing set upgrade at the same time. Of course, if I do this then I'll be pulling the front apart, so I might as well do an oil pump rebuild and replace the water pump. Scary how expensive things get when you start using logic isn't it?

So, here's my dilema...

My Jeep (78 Chero NT 360/Auto) isn't going to see a whole lot of off-roading, and at most will only have a 4" lift with 31's and possibly a change to 3.31 gears (stockers are 3.07). Now the Air-Gap intake is rated for 1500-6500rpm, so I don't know how well it would work with a cam designed for much lower RPM's (i.e. the Summit 8600 or Comp XE256H). Anyone know?

Now assuming the answer to the question above is "not good", I've looked at cams designed for a little higher rpm range. The two that look the most promising are the Comp Cams XE262H or their 270H Magnum grind. Both "should" work well as my highway cruise RPM with the 3.07 gears is 2300+ (2100+ if I go to 31" tires). Cam spec's are as follows:

Xtreme 4x4 XE262H Grind
Duration @ 0.050" Lift = 218*/224*
Lift (1.6 rockers) = 0.493"/0.500"
Lobe Separation = 110*
RPM Range = 1800-5800
Notes: Excellent Response, good mid-range, noticeable idle

Magnum 270H Grind
Duration @ 0.050" Lift = 224*/224*
Lift (1.6 rockers) = 0.480"/0.480"
Lobe Separation = 110*
RPM Range = 1800-5800
Notes: Best cam for 360-401 engines with stock converter. Works well with headers and aftermarket intake. Mild rough idle.

Both would require higher rate valve springs, but that isn't a problem since I'll be replacing the originals no matter what I go with. My main concern is with driveability and how well the whole package would work together.

So, what I'd like to know is if anyone is running either of these cams (or has in the past), and if so how did they work out? I'm willing to trade a little bottom end for increased top-end power but also don't want to shoot myself in the foot. This is a 5,000lb vehicle we're talking about, so I want to atleast keep the same amount of torque off-idle as the factory cam provides.