Ok so I removed my evo 8 head because I knew I had at least valve damage. I later found that I had 2 pistons that had wear from the valves hitting them. They were on the 2 right cylinders. I know I have to replace the pistons now but what is the possibility that anything below the pistons got damaged? Im sure someone has been in my shoes before so just let me know thanks.

If any questions I have a fully built 2.0 With AMS/Ross pistons.

 

How do you plan to remedy the piston/valve clearance issue? Why did your engine have the interference anyway?

 

All I plan on doing right now is replacing stuff. I really dont know what caused the issue except maybe the 33PSI I was running. I wont be doing that again for sure lol. I also put in bigger cams went from HKS 264's to Tomei 280's. Im guessing the valves didnt get bled or just that the duration was too big for the set up. I really dont know at this point.

 

It's unlikely that the valves hitting the piston would cause any damage to the bottom end (besides the piston damage of course) but you need to find the cause of the interference so the problem doesn't happen again. Things to look for are;

Deck height. How far is the piston sticking out of the block?
How much was the head milled?
Valves could have been floating/bouncing.
Weak/incorrect valve springs. High boost levels can overcome the spring pressure and hold the intake valves open.
Cams out of time. Did the intake and exhaust valves make contact with one another or was it just the intake valves hitting the pistons?

 

After AMS built the motor the head was never touched and it was stock when they got it, so I dont think the head was milled at all. I do think though that the valves were not bled correctly after the new cams were installed.

I will measure the piston height thanks for that idea, I got a fully built head also but if the valves we floating wouldnt they do that on all 4 cylinders?

 

bump?

 

you cannot bleEd valves kimo.....

 

You need to check your piston to valve clearance. This can be done by putting clay on the crown of the piston, then putting the head back on and rotating the assembly. This will give you a starting point. You should have over .100" clearance (some run it a little tighter). If you don't have enough clearance, now you should find out WHY. See the message above by Jackson Auto Machine for potential problems. If you find you have enough clearance, then your valve springs may not be sufficent. You will need more spring pressure to keep the valve from floating.

Check everything before you put it back together (including cam timing) to save yourself the hassle in the future!