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LS Tech: How to Delete Variable Valve Timing (VVT) on an LS Engine

 
GM LS Valvetrain

(Image/GM EFI Magazine)

Variable Valve Timing (VVT) is a system that automatically adjusts valve timing.

GM used VVT on the following engines within the LS family.

LS VVT Applications

DisplacementRPO Code
4.8LL20
5.3LLC9LH9LMFLMG
6.0LL76L96LC8LFALY6LZ1
6.2LL92L94L99L9H

(Summit Racing’s Paul Spurlock and Brian Nutter contributed to this article.)

How Does VVT Work?

The computer senses engine load. It also monitors valve timing through the camshaft position sensor. It then uses that VVT data to determine the best valve timing for the current conditions.

The computer sends a signal to a solenoid on the timing cover. The solenoid controls oil flow through a special control valve in the camshaft bolt. The valve sends oil into the phaser control chambers.

The actuator rotates one way or the other, depending on the oil flow. That rotation is used to advance or retard the camshaft as needed.

How Does VVT Affect Performance?

VVT gives you the best of both worlds. It can advance valve timing for a smooth idle and low-end torque. It can also retard the valve timing for more top-end power. And, it’s all done automatically.

VVT becomes an issue when swapping a cam:

  • Piston-to-valve clearance can be a problem.
  • Your choices for valve lift and duration are limited.
  • The high spring pressure required for performance cams can overpower the actuator.

If you want to upgrade your camshaft and keep the VVT system, you will need a Camshaft Phaser Limiter.

If you want high performance from a bigger cam, you will need to delete the VVT system. (More on that in a second.)

How You Can Tell Whether Your LS has VVT

Engines with VVT will have a camshaft phaser actuator on the timing cover. They also have a five-pin connector for the VVT and camshaft sensor.

Engines without VVT will not have the actuator. They only have a three-pin connector for the camshaft sensor.

LS Gen 4 Timing Covers VVT

These are two LS engine timing covers. The one on the left has the camshaft phasing actuator, indicating that it is from an engine with VVT. The one one the right has no actuator, so it is from an engine without VVT. (Image/Summit Racing)

GM used two different actuator designs.

In 2007-08, the actuator has 62-degree rotation. GM part number 12585994.

In 2008-15, the actuator has 52-degree rotation. GM part number 12606358.

How Can I Delete the VVT on my LS Engine?

Eliminating the VVT system is required when swapping to a non-VVT camshaft. These cams offer higher valve lift and longer duration for more performance.

A VVT delete kit removes the VVT components and replaces them with standard parts. At a minimum, they include:

  • A Gen. 4, non-VVT timing cover
  • A new, 4X, non-VVT upper timing gear
  • A new harmonic balancer bolt
  • New camshaft bolts

Some kits will also include additional parts, such as:

  • A new lower timing gear
  • A new timing chain
  • A new timing chain guide

The type of VVT Delete Kit you need depends on the camshaft you are using.

1-Bolt Camshafts

3-Bolt Camshafts

Eliminating the VVT system is required when swapping to a non-VVT camshaft. These cams offer higher valve lift and longer duration for more performance.

After installing one of these kits:

  • You will be locked-in to the valve timing.
    • The computer will no longer automatically adjust the valve timing.
  • You will also need to tune the computer.
    • This will optimize the fuel and ignition curves for the new camshaft, and turn off the VVT system in the computer.
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23 Comments

  1. Pingback: Video: GM LS Cam Swap Tutorial - OnAllCylinders

  2. Pingback: LS3 Engine Upgrade Guide: Expert Advice for LS3 Mods to Maximize Performance - OnAllCylinders

  3. Norm FRENCHY LaFountaine says:

    Is there a link to INSTRUCTIONS on removing the VVT components and replacing with the VVT Delete kit?

    • OnAllCylinders Staff says:

      Hey Norm, replacing the VVT components is much like doing a cam swap. Really the upper cam sprocket is the main difference. You can find directions to performing a LS cam swap HERE.

  4. If i put a motor with vvt system into a truck model without the vvt system
    Can I just not plugging it or i need vvt cancel kit ?
    I apologize for my writing , I’m not really good in English.
    Thanks .

    • Etienne, your English is just fine.
      If you used the ECM and harness from the VVT equipped engine, it will work. If you tried to use a non-vvt ECM, the engine will not perform well because the cam would always be in the “parked” position.
      The phaser moves as much as 62 degrees, so you can imagine a camshaft being in the wrong position the majority of the time. It would be much better to install a VVT delete kit and a non VVT cam before you put the engine in the vehicle.

      • Can i put a 2013 4.8 into my 2005 Express (4.8 with 250k miles) with the VVT delete kit and keep the installed cam? (not a performance application)

        • Mike, the 2007-09 LY2 and 2010-17 L210 model 4.8s were gen. 4 engines with a 58x reluctor ring on the crank. A 1999-06 LR4 is likely what you have in your 2005 Express and it came with a reluctor ring. Those engines and ECM were set up for a 24X reluctor ring. To run the later model engine in your truck would require the ECM, Harness, and pedal to work.
          Then there is a question of whether it would work with your dash or gauges without issue. With your 24X ECM, it would be best to find a LR4 or one of the four different Gen. 3 5.3s to swap in (LM4, LM7, L59 or L33).

  5. If you use a VVT delete kit can you use say edge and diablo tuner that turns the VVT off? or do you need to send the ecm off to have it tuned out?

    • OnAllCylinders says:

      If a disabler is used, it will not need to be turned off inside the ECM. If you’re looking for added performance though, a tune is well worth the money.

  6. Is there any gen. 4 model of the ls 6.0 made without vvt or should I just go with an earlier gen motor for a c10 motor swap?

    • Joe, Gen. 4 6.0’s iron blocks will all have VVT. With VVT delete kits being fairly inexpensive, you don’t have to be too picky when a good deal on an engine comes your way.

  7. can i install a 2010 6.0 with vvt in my 2008 silverado non vvt do the vvt delete and keep the vv. cam in the motor

    • You can put the 2010 model in your 2008 with the VVT delete kit, but you will need to backdate to an earlier style cam. The VVT camshaft itself would have the wrong timing events in a standard engine. A stock replacement cam would this one from Melling.
      If you wanted to give it a bit more pop, the Summit Racing Stage 1 truck cam is a great choice. With that cam, an ECM tune is a plus, but not required and it works fine with the factory valve springs.

  8. Pingback: LS9 6.2L Engine Upgrade Guide: Expert Advice for LS9 Mods to Maximize Performance - OnAllCylinders

  9. i have 6.0 block with vvt system 2008 … i swap cam ls1 comp cams + ls1 harness .. do i need this kit to delete vvt and use standard cam sensor ?

    • The 2006+ 6.0L engines were all Gen. 4 with the 58X reluctor ring on the crankshaft. If you are using the LS1 ECM, it will not work. If you do have the Gen. 4 late model ECM (and front timing cover mounted cam sensor), you could use your normal COMP Cam and a VVT delete kit along with tuning.

  10. Nathan Polk says:

    I did a cam swap on my Chevy 2013 4.8. I did the VVT delete kit ( swapped timing gear, cover, etc). Since there is no where to plug in the ‘VVT’ plug into the solenoid, what am I supposed to do with this plug? How to remove it? It’s only purpose is the other plug attached which is plugged into the cam position sensor. and the plug that used to go into the vvt solenoid is just dangling there… thoughts? is this a problem? truck has been tuned and all. How to remove without damaging cam position sensor wire

  11. Aaron Hitchcock says:

    I have an 07 Denali 6.2 that’s losing oil pressure, can I use a cheaper iron block 6.0 and install a vvt setup on it to save some money? Or my 2nd option can I install a 6.0 without vvt and just have it tuned to keep cel off without it there?

    • The L92 is a great engine and didn’t have AFM to deal with.

      You may have done it already but if you are losing oil pressure, the first thing to check would be the small filter (p/n RNB-917-143) underneath the pressure sensor at the back of the intake manifold.

      If you’ve ruled that out, a 6.0 without VVT or with a VVT delete kit will work if the weight gain from an iron block is acceptable.

      You will be looking for a L76 Truck engine with an AFM delete kit, L96 (with your present intake manifold/injectors), or LY6 which would be the most direct swap.

      Of course swapping your top end onto a ATK HPE-SP71 415 short block and a SUM-8712 cam is always an option.

  12. Hello! A lot of good stuff here!! I have a 11 Silverado 5.3 with vvt and dod I recently switched the cam with a tsp vvt camshaft and locked out the cam phaser as well as did the dod delete , new springs, hardened rods, ls6 lifters etc. I did a get me by tune with the diablo sport tuner on mid grade tune as well as deleted the dod electronically.. my question that I can’t seem to find is. Being I locked out the cam phaser my check engine light remains on for the cam position sensor I’m assuming because my ecm is calling for more advance or retard than what it can make because of the lockout? How would I go about getting that tuned in? Is it fine like this and if so can I some how clear the code for good

    • Frank Mahlau says:

      You’ll have to have the tuner/tune change/ed the limits the cam sensor and the phaser Is reporting. I think you’re right, in that the one isn’t matching what the other expects. Is the tune you have a canned tune, or can you touch base with where you got it? My guess is it was an over site or a glitch when the new tune was made or flashed. Btw, how is that build going for you. I have a similar one planned in the near future.

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