Well, your 4runner has a 2.7 liter in-line 4-cylinder (not V4):
ENGINE
2.7-liter, 4-cylinder, 16-valve, dual-overhead cam,
EFI, cast-iron block with aluminum alloy head
Bore X Stroke (in): 3.74 x 3.74
Displacement (cc): 2694
Compression Ratio: 9.5:1
Valve Train: 4 valve/cylinder
HP (SAE Net): 150 HP @ 4800 RPM
Torque: 177 lb-ft @ 4000 RPM
Ignition System: Electronic
Fuel System: EFI
Recommended Fuel: 87 Octane Unleaded
Emission Control: Closed loop TWC
It is a good 4-cylinder truck engine.
Here is link to the complete specifications of your 4runner:
http://pressroom.toyota.com/photo_li...=19994runner_s
I believe there is a TRD supercharger for your engine...however, it will cost you about $1500-2000 from Toyota. You can change little things (ex: air filter, intake, exhaust, etc.); however, these changes will not make much difference.
I would not recommend any more engine mods to your 4runner. You would likely just waste money. It's a rough-and-tough truck...it is not meant for speed. If your friends say that your truck is slow, just tell them to follow you thru an off-roading place...they will then have much respect for your 4runner!:gaptooth:
Hope this helps.