Hello TB!!
Like the title says -
Took a smoothly running b200ft (had a 530 with whatever cam there was, stock).
Put a 531 head w/ a VX3 cam on it.
Before that, sent the head to a shop for checking. Shop said it's heavily skimmed. Dono how much exactly thought.
The shop gave the head a refreshing - making sure that all surface are level (deck, valves, seats).
Result is a lumpy idle, pulling a steady 14"-15" vacuum (was pulling 18" on 530 head).
There are no vacuum leaks.
Pulling 21" on deceleration.
No signs of wear and tear on the cam.
Valve timing seems to be set correctly.
Can this be caused by the elevated static compression? Due to a heavily skimmed head?
OR
Should I start suspecting that the head shop did a poor job of verifying that all surfaces are level? May be caused by valves that do not seal/sit perfectly?
If so, any way to test for it w/o taking the head off?
*all vacuum figures above are in - hg/in.
Thanks in advance!!
Matthew.
Like the title says -
Took a smoothly running b200ft (had a 530 with whatever cam there was, stock).
Put a 531 head w/ a VX3 cam on it.
Before that, sent the head to a shop for checking. Shop said it's heavily skimmed. Dono how much exactly thought.
The shop gave the head a refreshing - making sure that all surface are level (deck, valves, seats).
Result is a lumpy idle, pulling a steady 14"-15" vacuum (was pulling 18" on 530 head).
There are no vacuum leaks.
Pulling 21" on deceleration.
No signs of wear and tear on the cam.
Valve timing seems to be set correctly.
Can this be caused by the elevated static compression? Due to a heavily skimmed head?
OR
Should I start suspecting that the head shop did a poor job of verifying that all surfaces are level? May be caused by valves that do not seal/sit perfectly?
If so, any way to test for it w/o taking the head off?
*all vacuum figures above are in - hg/in.
Thanks in advance!!
Matthew.