yes it is high compression... though obviously adjustable with pistons. also, if you don't want to do an expensive all motor build, the rods, pistons, crank and head internals are more beefy than a h22, the cams are more aggressive and it has iron sleeves - in general, a much more sturdy motor for boosting if you don't want to do expensive upgrades to make the parts hold up. plus, i hear you can make turbo work ok with high compression - just takes some know how and a great tune. it's not high enough to make turbo impossible - static compression is 11.0 stock. i think flat top pistons with a 1.1" compression height would bring you down to about 9.7 compression which would work just fine for boost - though it would make for even worse low end power until it spools up.