So i did something stupid. Long story short, i cliped a turbine blade and broke one. So now im in need of a new turbine wheel. Is the MHI 9 blade a direct replacement for the MHI 12 blade in a greddy td05 18g? Any machining of turbine housing needed? Any benefits?

 

Depends upon the 12 blade used. You have to concern yourself with *snicker* shaft length /width. The 20g turbine wheel should fit. Check with kinugawa. They should have them

 

It's just the stock 12 blade in the greddy 18g. Kinugawa has the 12 and 9 blade versions for the 18g. Did some reading on the 9 and "they" say it reduces turbo lag and improves response time also it's lighter in weight. But I'm sure that there's a "gotcha" somewhere in there...

 

The 9 blade is for the TD04L line, which is much smaller than the 18G. What you're seeing as the 9 blade was more than likely the turbine shaft that would fit the TD04L 15G from GReddy. Not the 18G.

You have to remember that the 18G was a Mitsu/Garrett Hybrid turbocharger and although used a 12 blade for the TD05H, used Garrett turbine housing..

Your "gotcha" is that the 9 blade is a different shaft width and use for the GReddy 15G and not the 18G. Not interchangable.


Get your caliper out and start re-measuring your turbine wheel / shaft sizes that fit into the turbine housing.

Here's what you need.

- Inducer: 55.8 mm / 2.19 inch
- Exducer: 49.1 mm / 1.93 inch
- Turbine Shaft OD: 9 mm / 0.35 inch

If they match up, winner, winner, chicken dinner

 

You are a winner winner who deserves chicken dinner. Seriously, thanks man.

 

will he need to re-balance the shaft? I would think so

 

Yes. He'll have to rebalance the entire assembly. He doesn't have to necessarily use a VSR balancer, but it does help.

 

The 9blade turbine is available for both TD04HL and TD04L. I would always go with 9 blade as the TD04 series turbos all have small turbines and are not able to flow enough exhaust gas at higher rpms. More flow= More top end lower EGTs And EBP. Win win. Also all MHI Turbos are Prop/component balanced already. You just have to line up balance marks on both wheels.