Very recently, VTEC has lost its edge at 4700 rpm, I actually feel the car slow down. It feels normal as far as I can tell through the RPM range up to 4700. I did plugs/wires, cap/button about 4000 miles ago. Pulled my plugs yesterday, and they're aleady wiped out, just put in new plugs this morning, VTEC still sucks. Sorry if theres already an answer to this, the search is F-ed! This isn't a swap, stock engine, 112K, only have short ram intake. One thing that may be a contributing factor is a cracked exhaust mani. could this throw off my A/F ratio? I have a replacement on the way with the o2 still in it, which hopefully helps. I really appreciate any pointers...