0

I am building a 450-500 hp honda civic with a d16y8 head, i purchased brand new valves , and i was wondering how do I get these valves to seat and seal the chamber for combustion? Is lapping the valves effective enough to ensure the head will hold compression or do I have to go the extra mile and get some precision machine work done??

0

If you lap them in and get a proper seal then machining is not needed.

If the new valves are supplied without the final surfaces angled correctly i.e. as a “blank”, then they need machining.

| improve this answer | |
  • Have a shop grind the seats and the valve faces for proper fit. You'll never get a good seal using new valves and old seats just with lapping compound. – user9181 Apr 24 at 18:40
  • 1
    @user9181 I had, perhaps erroneously, assumed that the head was new and the OP does state clearly that the valves are new... – Solar Mike Apr 24 at 18:44
1

Since it is high performance, I would let a reputable automotive machine shop do a 3 angle valve job. Better flow and performance and everything gets checked, including checking for cracks in the aluminum head. Have it surfaced for a good head gasket seal also.

Find a machine shop that has experience in performance work.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.