Wiseco DSM HD stroker pistons 8.5:1 not 9:1

[nastyleak]

The compression ratio listed by several DSM vendors shows these pistons with a 9:1 CR, which is not accurate according to Wiseco. This may not make much difference to most people but I actually wanted more not less compression. Wiseco pistons have an excellent reputation so I just decided to have some custom made. Please let me know if someone can confirm or disprove the CR of these pistons: WSC-K627M85. It seems impossible that the same pistons could have the same CR in an Evo and in a DSM as well.
Wiseco's online catalog shows the correct-updated information.

 

[zedicus]

you are correct that they are not really 9:1. but there are a lot of variables that go into accounting for that raiting. some builders rate based off of stock block speck, some take decking into some concideration, even the gasket can change it a point or 2.

im having wiseco cut me a set of stroker 86.5mm 10:1 pistons and i told them to error on the high side if anything. the price difference in custom cuts is not much, the bad part is waiting for a month while your turn in line for custom cutting comes up. if yours could be made out of one of their standard blanks your wait time may not be that bad. at 10:1 and this bore size and stroke mine are fairly unique.

 

[mschlanglv]

With both the block and head decked, my CR came out at 8.8:1 with these pistons. Unless you break out the buret and accurately measure everything it's only going to be an estimate and guess.