BogusSVO
Well-known member
Oil port mod #2 for 4G63T
The head is a 2g head going on a 1g 6 Bolt short block.
This head has had oil port mod 1 done.
click
The head bolt holes have been reamed for the 1g head studs. To prevent any issues with oiling issues in the head, I have reamed the bolt hole that is in the path of oil flow to .500 the bolt hole was .470 the ARP head stud being used is .465 Leaving only appox. .005 total or .0025 clearance on either side around the head stud. I feel the addition .030 will alleviates any problem with oil into the head.
All ten head bolt holes need to be enlarged to .500
The head is a 2g head going on a 1g 6 Bolt short block.
This head has had oil port mod 1 done.
click
The head bolt holes have been reamed for the 1g head studs. To prevent any issues with oiling issues in the head, I have reamed the bolt hole that is in the path of oil flow to .500 the bolt hole was .470 the ARP head stud being used is .465 Leaving only appox. .005 total or .0025 clearance on either side around the head stud. I feel the addition .030 will alleviates any problem with oil into the head.

All ten head bolt holes need to be enlarged to .500