Tired engine

[turbo400ex]

Have a 1999 400ex with a tired engine. What can I do on a standard rebuild to increase HP with a budget of approx. $300 ? Labor and shop time is free. Already have jet kit, air filter and pipe. Want to get the most bang for my buck.

[zlam27]

big bore kit - $250
cam - ($125-$200)

either one of those should give you some great results

[tater_kamik]

i definately agree, an piston and an cam, spend some time porting and polishing, maybe shave the head down a little, take the choke plates out of the carb, and you should be running like a new quad!

[bwamos]

Bore out the sleeve.. 0.020 or 0.040 over (mainly because of the wear) and go with an 11:1 compression piston. The added compression is HUGE. ;)

If you have a little extra cash left grab a cam. With the cam because of the age.. you will need to replace the rockers. Web you will need to get your existing ones hardened. Web + Hardened Rockerswill definatly be your cheapest option at this point on the cam side.

You will not be dissapointed. :D