Hi ! If I want to install 1968 430 cylinder heads (1382091) on 1972 455 block (1238861). Do I use the 455 pushrods, and plug the oilchannel on the 430 heads? I remember I needed to plug something, but can't remember if it was the heads or the block. Is there any good guide out there how to do this? I noticed that TAPerformance sells adjustable pushrods. And hybrid for oil thru the pushrods but still early style rockers. Do you guys recommend me to buy these? Thanks
I just plug the hole in the block driver side,..aluminum stock drove down in there,..bolt shank,..thread and tap
https://www.diyauto.com/manufacture...55-block-id-prep-and-oiling-mods-by-jim-weise You have to scroll down a lot, so here is the parts you need,
I think he's saying he wants to use the 430 heads on the 455 block. If thats the case there should not be any hole in the block to plug. Just use 455 rockers , lifters and push rods.
Yes there is Briz. All 455 blocks have that hole, JUST on the Driver's side. Read JW's description I posted.
My over site but now I wanna know why Buick continued to cast blocks with a oil port that was not needed. Inquiring mind!
This is not the proper way to do it but I simply filled the hole in the cylinder head with RTV and bolted the rocker shaft on.. no leaks or issues. This is on a 430 with later rockers on it...
Which holes on the 430 heads did you fill with RTV? i am looking to do the same 430 (69cc) heads on a 455 block.
Why would you do that when post #3 shows you the proper way? There is only one hole to plug on the 455 block.
The bolt holes for the rocker shaft have the oil feed for the rockers. Its the first rocker bolt on the left side and and the rear most bolt on the right side. Look at the head without the rocker shaft and its obvious. Fill the hole as much as possible and your good. I did this 10 plus yrs ago and probably 20k miles ago. Undoubtedly this is the proper way to do it. No arguement there at all. But, after the conversion to pushrod oiling i found there is very little oil pressure or volume at those feed lines. After all there are 16 pushrods bleeding off the top end pressure. Those feed holes would be sealed with your finger if it was possible. I don't think it's an issue at all. Hell the factory left the driver port open without consequence. It's not a plaguing oil leak on 70-76 455s..
Agreed, probably not a problem in most cases as the head gasket will seal it (maybe not if you step up the oil pressures). As JW explained it, the factory left the driver's side open because they had to.
The 350 blocks have the same hole, the "oil thru the pushrod" heads do not have a "receiving hole" to the #1 rocker tower. Buick relied on the head gasket to hopefully seal a potential leak being the oil still passed thru the hole in the gasket but was stopped at the head, as Larry said, 38-40 psi stock pressure it was marginal, but at 60 plus, its probably going to weep unless its stopped at the block by tapping and screwing, aluminum rod, or RTV.
