Ordered and recieved a K&N clamp on from HyperRacing.com, but still waiting for HPD to unveil their pipe. Called them last week and they said it should be this week or so, but I'm not holding my breath. Anyway, I'm wondering if it would do me any good to put the K&N on with my stock exhaust? Anybody notice any gains at all from this? Did you have to mess with the jetting? Thanks in advance!