Yeah, i agree with Peter, headroom is a problem for 4runners for the longest time now, including the new 4th gen 4runner.
The 4.7L V8 engine is a piece of art. It is ultra-smooth (at all RPMs) and extremely bullet-proof. There has NOT been ONE recall on it since 1999 (when it was a brand new design--see below)! It has great low-end torque. HP is a bit low, but this is because of the torque rating. Off idle, the engine makes at least 80% of its torque! It is efficient (above average fuel economy). It is really clean for a truck engine (ULEV rated). This engine has been around since 1998 or 1999, when it first appeared on the Land Cruiser. Since then, it has received praise from around the world as being one of the top truck engine.
FYI, this engine has it's roots from the Lexus LS400 4.0L V8 engine. This is why it is so darn smooth and quiet. However, Toyota went ahead and made total revision to it for truck duty. This included lowering the compression ratio and enlarged it to make more low-end power (but losing some HP in the process). They also changed out the aluminum block in favor of IRON block for durability/toughness. (Of course, this is great if you ever get into supercharging because iron block is damn strong!)
For 2003, most of the Toyota SUVs with the 4.7L V8 engine get a 5-speed auto transmission. This transmission has a stronger first gear ratio, allowing for better off-the-line acceleration, better towing, and better off-roading (higher crawl ratio). It's overdrive gear (5th gear) is about the same as the previous 4-speed auto transmission...thus, fuel economy on the highway remains good.
As for 0-60 mph, the 4runner V8 is probably the same as the Jeep GC V8, but is a tad slower than the Overland model with the HO engine.
BTW, if you look at the Jeep's 4.7L V8 engine (both regular and HO), then you will see that it's torque curve is not very good. The torque curve is NOT flat, but rather peaky (most in the midrange RPMs; not so good at low end). The Toyota's 4.7L V8's torque curve is flat as Nebraska's flatlands! Torque is available at all RPMs in the Toyota engine.
As far as room is concerned, you have to decide that for yourself. There's always the Lexus GX470, which has more headroom and a bit more legroom than the 4runner. It is also more $$$$.
The 4runner is a bit too new for any significant mods, especially off-roading stuff. However, TRD does have a supercharger for it if you're in the mood.
Hope this helps...and good luck in your purchase.
