Hello, I am in the processing of assembling my 76 .030 455. About a year ago I enlarged the main oil feed oil on the block. One of the mod's was to enlarge the oil feed hole that goes through the oil pressure sending unit through to the number one cam bearing . I beleive that I enlarged it to one half inch. This was a year ago. I remember reading that this particular size (if I am correct) would allow you to enter the feed oil without any damage to the threads on the sending unit. That is what I did. No damage to the threads. My question is, I drilled all the way through to the number one cam bearing. I did not see any instructions that said otherwise. I have read post's that have said that it would serve no purpose drilling just shy of the cam bearing journal and that going all the way through would be okay. I drilled the angle correctly and had no problems. The journal and the oil hole cleaned up fine. Is this acceptable? I also installed ta's fully grooved bearings. Thank you, Jon Thomas Alamo Heights, TX. jthomas1248@satx.rr.com
Jon I think that was a 7/16" hole, because the drill bit I had was a bit short, so I used a .440" reamer (which was longer) to finish the hole. But the important thing here is to RECHECK the latest oil mod recommendations. I'm not sure of the specific diameters, but it was also recommended to drill from the mains to the cam bearings, and another hole on the timing cover. You can do a search here, or go to buickperformance.com (I think they have the latest rec's. And as for the question about drilling all the way thru, yep, I did it too.ou: As long as you are using the dual groove bearings, you should be fine from what I have heard. Then again, what else can you do about it now?o No:
Jon I posted a thread about this awhile back. See Jim Burek's post(buick535). http://www.v8buick.com/showthread.php?s=&threadid=14415&highlight=oil+passage
I think Jim means 5.25 inches deep on #1 and DO NOT go thru the journal. On #2,3,4,5, go thru with a 23/64. Jim, if you're out there, is this correct?
oil mods To all of the 455 guys and gals that have drilled out the oil passages in their motors, how hard was this to do? Was it worth the aggravation? Also, once upon a time there was a thread refering to drilling and tapping of the passenger side oil galley on the back of the block to attach the oil gauge or sending unit there. Does anyone have any pictures or instructions to do this?o No: Help! Tony
