It is going to be between 9:1 and 10:1. It's impossible guess better than that without taking the engine apart.
Here are some 100% accurate guide numbers for you base on your motors current Bore and stroke. Here are the CC numbers ( total volume ) you will need above the piston at TDC get a certain compression ratio. For example . 9.5 to 1. 99.43 CCs 9 to 1. 105.73 CCs 8.5 to 1. 112.7 8.0 to 1. 120.7 Basically if for example you had a total of 112.7 CCs, then every change up or down of 6.5 CCs will change the compression ratio by 1/2 point in regards to you motors current Bore and stroke.
