hey guys, i just recently got some headwork done on my 420a and replaced the rings and seals in the block. I also gt a stage 1 clutch from clutchmaster and a fidanza flywheel. so how should I be breaking in the engine and the clutch? I hear alot of conflicting methods and dont know which to believe. Also, i figured i wont have a crazy amount of hp seeing as how im n/a but how much hp do u guys think i have with a 3 angle valve job, a slightly milled head, port and polish job on the head, cai, dc sports headrs, lightened crank pully, fidanza 8lbs flywheel

 

If you want a full guide how to break in an engine and WHY it is that way... look here: http://www.mototuneusa.com/break_in_secrets.htm

Now... for the clutch. You want to avoid any kind of racing, aggressive shifting, agressive launching for roughly 300 miles for the best results.

I will tell you now... thats the way to break it in. I have built many small 4 stroke 250cc motors for competition go kart racing and my engines come out with roughly 31-32hp and the otehrs can be as low as 28. This method is proven and i will gladly stick my neck out for that.

 

Sebb is right on for the break in info. For the hp, greather then 140 bhp and no more then 190 bhp, my guess 170ish.

 

really? when i saw that article i thought the guy had been sniffing fumes or something..... so running your car super hard right after a rebuild is good for the car???? i'd like to try it but at the same time if something goes wrong i'm completely screwed and have just wasted my money rebuilding my bottom end.

 

well your only supposed to drive it hard for like 20 miles or so right. Just to get a better seal. Then after that go back to normal driving

 

Yes exactly.

You just ened to put load on the engine and let the engine decelerate on its own without using the brake. 3rd is a good gear to use.

Also changing your oil as frequant as possible will also resuilt in better life.. like... after the 1st 20 miles of driving.

 

aight good to know.... i'll give it a wirl when i rebuild my engine. thanks guys.

 

i appreciate u showing me that article. im following its advice exactly so we'll see how it goes. i have 500 miles put on after the rebuild so once its all done ill put in on a dyno and tell u guys what hp it put out

 

yes please do i'm VERY curious to find out!! i wanna know what to expect when i get mine rebuilt

 

There will be lots of white and blue smoke then you do that break in method.. so dont worry.