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Engine Stage 2
Turbo Dynamics Hybrid Twin Scroll Turbo
What is a Hybrid?
Well, taking a standard turbo and modifying it with either brand new designed parts or parts from existing turbo’s available gives the term of “Hybrid”. It’s as simple as that (well, not quite simple as regards to what has to be done, but simple as regards to explaining what the term means).
Upon receiving the turbo charger it didn’t look any different initially (to the un-trained eye) than the standard one sent to Turbo Dynamics as the donor. Whilst a number of changes can be made that are hidden to the eye (as they can be internal), the use of the generic term “Hybrid” being used you would half expect some kind of item having other parts stuck on to it. Obviously this could not be further from the truth as modifications made to units takes a lot of thought and experience to gain the required results.
Looking closer (or more importantly, knowing what to look at) it is clearly evident that a number of changes / modifications have been undertaken by Turbo Dynamics.
 The picture to the right shows the Inlet of the original Twin Scroll IHI VF36. As you can see it clearly shows 6 blades on the wheel.
 The Picture to the right shows the Inlet of the Turbo Dynamics Hybrid IHI VF37. As you can see it clearly shows 5 blades on the wheel, which are actually double edged. This changed Inlet Wheel design is to increase response, thus decreasing lag.
 The picture to the right shows the standard VF36 exhaust side. The top left hand corner is the exhaust wheel and the bottom right is the internal wastegate. Notice the "rusty" colour. This is due to the use of Octane Boosters, but nothing to worry about.
 The picture opposite shows the exhaust side of the Turbo Dynamics Hybrid Twin Scroll turbo. At first you notice that both turbos look different on the exhaust side. This is primarily due to the fact that the hybrid was based on a standard VF37, which is from the standard STi Twin Scroll car and differs slightly to the VF36 which is a Spec C specific turbo. Since the turbo was being made in to a hybrid, the donor turbo type (either a VF36 or VF37) was not an issue. The main point worth noting, although quite difficult to see on the image, is the exhaust wheel on the hybrid turbo has cut-back blades.
What did all these changes mean? Well we wanted to improve mid range response without sacrificing low down torque. So Turbo Dynamics used the latest 5 blade high response compressor wheel with a modified cover (instead of the standard 6 blade design) to improve the lowdown spool. They then modified the turbo shaft with cut-back blades to allow the turbo to breathe more easily at higher RPM. Would it work..... lets find out.
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