Diesel Tuner's Blog

Drop-In Turbo Option for LLY, LBZ and LMM

Posted by Paul Wilson on Mar 7, 2017 1:00:00 PM



Duramax VVT Upgrades:


The 2004.5-2005 LLY was the first model Duramax to be equipped with a Variable Vane Turbo (VVT).  VVT  technology provides quicker spool-up, better EGT control, and better overall boost control.  This is also commonly referred to as a VGT or Variable Geometry Turbo. 

To understand the basics of a VVT or VGT technology take a look at this VIDEO on YouTube.

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The stock Duramax VVT turbo from 2004.5 until 2010 is similar.  Slight changes to each model (LLY, LBZ and LMM) were made in compressor size, aspect ratio, blade profile and other features.  Despite these changes, you will find the same peak power potential of approximately 530 RWHP.  As a Duramax performance enthusiast this is probably just not enough power to keep your interest for long. 

There are many upgrade options on the market.  Deciding which one is the best for you can be tough.  An endless amount of forum threads and user stories makes it challenging to decipher fact from opinion.  

Stealth 64 Turbo Product Links:

Stealth 64 VVT:


The Stealth 64 VVT project has taken a stock appearing LLY/LBZ/LMM turbocharger and overhauled it to meet the demands of the Duramaxtuner team.  

stealth 64 vvt.jpg

The stock LLY/LBZ/LMM  turbocharger runs out of air at about 530rwhp.  It has trouble controlling egts on extended pulls past 400HP.  The Stealth 64 VVT extends the useful power curve of the engine out another 120HP to 650rwhp.  Furthermore, the Stealth 64 VVT is much better at controlling exhaust gas temperatures under sustained load when towing up long grades at high power.  This is accomplished through the use of a specially designed billet compressor wheel which is matched to a higher flowing turbine assembly.  This match represents the best balance between quick spool-up response for driveability and overall compressor flow for peak power for truck owners looking to make 650rwhp. 


 Stealth 64 613 HP.png

The Stealth 64 VVT is an easy to install upgrade that spools up quickly, controls EGT's under heavy load, allows to turbine braking during towing scenarios, and kicks ass when leaned on. 



Will it work for you?

This turbo is perfect if you have a built transmission or if you plan on building it soon.  The factory Allison found in these trucks can hold 400 - 430 RWHP.  Although you can run a Stealth 64 VVT with the stock transmission, you will not use it's full potential unless you can put the power on the ground.  

We also find it is a good match on stock injector trucks.  Stock Duramax injectors are capable of producing 600 RWHP when healthy and properly tuned.  They just need a turbo like this to get there.  A lift pump will help support your Cp3 (high pressure fuel pump).  

No plans on building the engine? Although this unit can be matched in a twin turbo application to make over 900 RWHP most guys running them want to keep the engine together.  

 - Street Truck, Daily Driver, Weekend Warrior

 - Towing on a regular basis

 - Stock Replacement but want a little more

 - Base for big Twin Kit down the road

Josh Wright LLY.jpg


If you got done reading this article and think you might be able to handle the awesomeness of the Stealth 64 VVT hit the button below. 

Request More Information about the Stealth 64 Turbo



Topics: LLY, LBZ, Turbo, Stealth 64, Stealth, LMM