i've heard that the 3k has flat top piston so the chamber is in the head where as the 4k has dished pistons so the chamber is in the piston ... does this mean if i put a 3k head on a 4k i will lose lots of compression.

Edited April 12, 200719 yr by aidaniel

No, Most 4Ks have flat tops. So by putting a 3K head on it will raise compression.

er... well i'm rebuilding a 4k and it doesn't have flat tops, its got dished pistons, what will hapen there? ... also what is a head off a 4k with dished pistons like on a motor with flat tops?

If you use a 3K head on a dished piston 4K you will lower the compression ratio.

A 4K Head from a dished piston motor on a flat top motor will give a huge unusable compression ratio and would probly have problems with valves hitting pistons.

 

If your doing a rebuild, i would just convert to flat tops and a shaved 4K head.

Edited April 9, 200719 yr by Robert

righty oh ... when i shave the head what would be the right amount to remove in mm from a stock head? coz i'll be doing it myself at work. i found out to get a shave and regrind job was going to cost near 300-350 dollars and i can't afford that while I'm still in school