20G vs 20G

[GSRWRC]

Hey guys, thought there might be some interest in this.
Picked up some 20G bits from Kando off eBay recently to build a couple of turbos to sell on Trademe. I noticed the normal rotation 20G compressor I got this time around was a fair bit chunkier in blade thickness than previous ones I have got from him. Was up in Auckland visiting my mate Dirk, (aka agent orange on some forums) who gave me a spare 20G he got via Greensource on the US eBay store. So here are the differences:

- The thickness of the centre section of the Kando wheel is much thinner than the Greensource one. The Greensource style is much like that of a standard MHI 20G (and Evo I 16Gs), whereas the Kando 20G has the thinner centre section like an Evo II/III 16G6. The thicker centre section effectively makes the inducer a bit smaller.
- The Greensource 20G has a pronounced curve on the leading edge of both the primary and secondary blades. The leading edge on the Greensource 20G's secondry blades are also much thinner.
- The Blade thickness of the Kando 20G is almost double that of the Greensource item.

So what does this mean?
The Greensource item is quite true to an original MHI 20G, whereas the Kando item is more like the new compressors MHI made. Much like comparing a 16G to a 16G6. This certainly doesn't mean the Greensource item is worse, the blade thickness and leading edge design are superior to the Kando item. I'll weigh the two compressors at work this weekend and see if theres a difference - expect a similar result as I got for the 16G vs 16G6. The Blade thickness could hurt response, (who knows though, without a back to back dyno test I can't be sure) but I have also had Kando 20Gs with thinner blades. The reverese rotation 20G I got from Kando was a better example (Sorry, no pics of it).

If I were building these turbos for myself, I'd probably go for the Greensource item if the thickness of the blades on the Kando item were as they are on this unit.

 

[GSR]

I've come across the same thing few months ago, both wheels were from kando and differed in the same way like the two you've described.

http://www.4gtuner.com/topic/18073-20g-compressor-wheel-different-versions/

 

[GSRWRC]

Between us, Dirk and I believe there are up to 4 different aftermarket "20G" compressors out there (Not including genuine MHI). I'd hazard a guess that Kando/Kinugawa have a couple of different suppliers in Taiwan making these for them.

The thinner bladed unit you have pictured in "top1.jpg" is the pick out of the three we have pictured between us. (I'm calling our two thick bladed versions the same). The casting of the Greensource item I think is still slightly superior, but the thicker centre section in my opinion is less ideal.

GTPumps also do an aftermarket 20G - I have no idea where they are manufactured, but they are different again. They also do some work to the leading edge of the primary blades, which i'm not a fan of.

 

[GSR]

So which one would perform the best in your opinion? Or are the differences we spot small enough to not even worry about?

I've got another comp wheel thats meant to be a geunine item as it came in a genuine box, its got the thin blades, thin centre section, straight blades
(like the thicker kando version) and its the heaviest of all (only by few grams, cant remember exactly as its been a while now since I've measured them side by side). And it has letter 'C' casting mark between the blades, if that means anything lol

 

[GSRWRC]

So which one would perform the best in your opinion? Or are the differences we spot small enough to not even worry about?

I've got another comp wheel thats meant to be a geunine item as it came in a genuine box, its got the thin blades, thin centre section, straight blades
(like the thicker kando version) and its the heaviest of all (only by few grams, cant remember exactly as its been a while now since I've measured them side by side). And it has letter 'C' casting mark between the blades, if that means anything lol

View attachment 8805 View attachment 8806 View attachment 8807 View attachment 8808

Hrmmm interesting. My first impression is that it's not genuine as it has the thin centre section and straight blades. Genuine MHI units have a slight curvature to the leading edge much like the Greensource item above, and as far as I'm aware, the 20G was never updated to have the thinner centre section by MHI (Like the 16G became the Evo III spec 16G6). It's just something aftermarket companies have done themselves.

That saying, it's certainly the best of the bunch so far.

 

[milkandoj]

Very interesting. Seems like a similar situation how PTE make garret knock of wheels that are slightly different to genuine garret designs.

What I'm also interested in is the TD06SL2 wheels that many of these aftermarket turbo come with, compared to a TD06H wheel that is much larger. The TD06H wheels is pretty large compared to a 20g wheels so maybe that why it not used or its copies used on 20g very often. I also noticed there were TD06SL2 wheels some with 11 blades, some with on more of one less blade as well.
It makes you wonder, the original wheels would have been developed with so much R&D and these companies knock them off and make changes, are they even tested properly.

 

[GSRWRC]

Very interesting. Seems like a similar situation how PTE make garret knock of wheels that are slightly different to genuine garret designs.

What I'm also interested in is the TD06SL2 wheels that many of these aftermarket turbo come with, compared to a TD06H wheel that is much larger. The TD06H wheels is pretty large compared to a 20g wheels so maybe that why it not used or its copies used on 20g very often. I also noticed there were TD06SL2 wheels some with 11 blades, some with on more of one less blade as well.
It makes you wonder, the original wheels would have been developed with so much R&D and these companies knock them off and make changes, are they even tested properly.

As far as I know, the TD06SL-2 is a GReddy turbine. It should have 11 blades rather than the 12 Blade TD06/TD06H Design from MHI. Plenty of copies of it floating around (The Kando ones I've seen are reasonable). Personally I consider it a bit of a stopgap between TD05H and the TD06 based MHI wheels.