Ok I just picked up a 2001 400ex last week with a blown head gasket. Got new gaskets and was putting it together and noticed 2 of the 4 holes on the cylinder for the head to bolt to are stripped. Guessing this is why the head blew. So, I'm gonna replace the cylinder and ater looking around ebay I found I can bump up to a 440 kit for not much more (around $400 for cylinder and wiseco or JE piston). Includes all gaskets etc... The quad already has a stage 1 Hot Cam. My question is will my stage 1 cam be OK with this set up and what exhaust do I need? Would like to keep price as low as possible. Thanks in advance for the help!

 

I ran that set up for years with no problems.

440 kit
stage 1 hot cam
HMF clamp on a full sys. is better.

the one on left has an Curtis sparks full sys. and cam the one on right has the stage 1 and hmf