Turbine Wheel Blade Count Variances
We’ve already covered the pros and cons of different blade counts for compressor wheels, so if you have not already read it and are curious, you’re welcome to check it out on the other post.
Compressor wheel is actually more of the main lead as it affects the amount of air intake, however, turbine wheel can be a big plus if matched properly with the compressor wheel. Kindly note that blade pitch/profile also have influences on the performance, to not go that far, we’ll only be discussing about the blade counts here.
We will compare between turbine wheels of 9 blades and 12 blades. The 12-blade turbine wheels spools faster as there are more blades to grab air, therefore it has a better lower end punch. However, more blades have a disadvantage of being heavier.
One of the advantages of a 9-blade turbine wheel is having better top end, it has a higher turbine flow due to less surface area on the wheels, this lead to higher boost and is easier to make bigger power than a 12-blade turbine wheel. However, it takes time until it spools up.
When upgrading turbine wheel, it is strongly recommended that you also upgrade the compressor wheel that matches properly so that you see significant improvement on the performance.