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97 850 overbored

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I have a 97 850 B5254FS bottom end that I took to a machine shop to have cleaned up.

We found that the block was slightly out of round. Decided to bore it out slightly. The original bore is 83.0mm (3.268") We bored it to 83.5mm (3.287")

Unfortunately after having it bored and honed with pistons in hand, my machinist found that the pistons we had were not going to work on this build.

So now I am stuck with a bored block and no pistons to go in it.


My question today is do you folks have any solid aftermarket internal engine component stores you frequent?

there isn't any reason I am boring it over sleeving it. If I can find pistons that will work for what I have bored already, I would like to go that route, otherwise I will have to sleeve it and use original equipment.


Thank you for reading, Volvo for LIFE!


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You bored a factory 83mm block to 83.5mm? If so I would just throw the block out and get a new one, or Darton sleeve it. The 83mm block is already prone to cracking, and with a .5mm overbore it will be even more prone. 

You said you might sleeve it so you can reuse the stock pistons? A proper sleeve job will cost well in excess of $2000 and will leave you with a block that can support more than 1000WHP. The forged pistons you have now will barely make it past 500WHP. You could just get a 2.3L block, hone it and put in forged rods and have a stronger engine overall. 


If you want to waste your money on 83.5mm for a stock sleeve block wiseco can make you a set. 

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