It looks like my 400 will need boring. Is it safe to bore it out to accept 430 pistons? I search for the info but couldn't anything. Thanks Harvey
Yes, the 400 will take 430 pistons. In fact, in the Poston and TA catalog, they recommend doing that. :beer
Hold up!!!!!!!!! :shock: '67 and early '68 blocks are a thin cylinder wall units. There was some documentation around about 10 year ago on this, but I can't remember where I found it. (Not sure if it's 100% true, but you never know!) I have a late '68 block that I was able to safely bore .085 over and put Ross light weight pistons in. Making it a 416 CID. Remember blocks were cast at different locations, so before you jump in, get it checked by a GOOD knowledgeable machine shop. B&J Auto Parts in Port Coquitlam is good and a few of us Buick racer use them. Talk to Grant he is the machine shop manager there and really knows his stuff, including Buicks. Pete
Hmmm... From what I have been told by some reliable sources is that the 400 cid's are just underbored 430's, Kenne-bell has said this. What do the two Jim's say about it? are the 400's underbored 430's or not? Thanks
Personally, I have not seen a 400 block that will not go to a 430. They have some really masively thick cylinder walls in those things. Jim Burek
Harvey, your talking about your 67 block right???? Make 100% sure first. It's your money!!! Get it checked! We can all tell you it will be OKAY,but remember once you start..... :eek2: Remember everyone thought it was no problem boring a 455 - .060 over, then they found it was hard to keep it cool enough to drive on the street. Also Pop Kennedy was building these in race cars, so he didn't have to worry about this type of cooling problems. Racecar are way different than street cars. Pete
so what do the jims say about the 430 block? i've got two and it would be nice to be able to build them as straight up 455s.... :Brow: obviously, i understand that all advice is subject to checking cylinder wall thickness on my particular blocks. :Smarty:
We carry Wiseco light weight racing pistons to bore 400s to 430s. They include rings and pins for $681.81. They are currently on sale for $649.95.
The only experience Ihave had with punching a 430 to a 455 was with a 69 block. The earlier 430's I have cjecked did not have enough wall thickness to do it. Jim Burek