have a marine 455 olds engine, one of many that was built wrong. the lifter holes don't line up with the cam! bad block!! all other parts are new so what other size block can i use for crankshaft to be compatible?

Asked by Mar 30, 2017 at 09:48 PM

Question type: Car Customization

understand that i'm talking about a classic 1973 455 oldsmobile engine that
was built for jet boats. i need to know what other engine I can use with the
same 455olds parts mainly the alignment of the crankshat?

8 Answers


You mention both the crank and the camshaft which are two different things. If you have some sort of custom engine where the cam lobes don't line up with the push rod holes then the heads would also have to be custom? Maybe you can elaborate on this issue.


From what I have seen online the marine blocks were the same as the car blocks. Check out this forum ---- http://checkmate- boats.com/forums/archive/index.php/t-15660.html


Sounds like the wrong heads. They mount up but go to another engine.

these 455olds engines where made wrong! the lifter holes don't match the cam lopes! now two of the lifters have mushroomed before they don't line up its the block. So i have all these new parts and 455s are very hard to find.can i use another engine size make in to a 45 with all the parts i have.


There are 455's around still running just get one from another year or model, It may have been a bad block or is now or your putting parts in it that are not matched but any way take it or the other block you get to a machinist first (always) with your parts (if already purchased) and let them machine the block to your needs, The block should of been to a machine shop set up for this to see what was done to it before and what needs to be done now and which parts work and which will not, buy those and take to the machinist to be matched and aligned, and balanced if needed.


Do you have Buick 455 parts?


Valve train geometry, wrong rockers/push rod lengths, valve stems too long ect timing off, wrong size cam for everything else, it all needs to be measured out perfect or the wrong parts all together. If the holes for sure do not line up then either the wrong parts are in it, I hate to say bad block (maybe a bad machinist later on) I just never heard of this. If at the factory it would have been melted down and turned into something else.


You say it is a marine motor was it set up to run reverse rotation? They usually had different cams ect.

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