14 replies to this topic

[RallyRed]

Hi,
Am I correct that all LS2s have roller lifters?
And, if so they must be a solid lifter?
Or can rollers be hydraulic?
Thanks

[yel327]

Here you go, nice pictures too. I believe all or most all production LS are hydraulic.

http://www.caspeed.com/gallery11/

[RallyRed]

Ta mate.

Back inside now and can see that the manual also suggests that they are def. rollers.

Looks like they are roller hyd.  - never knew they existed.

 

Just chasing an issue on my son's LS2.

Found that #2 cyl. inlet valve does not move at all ( cranking by hand ).

All other rockers/valves move as expected.

#2 inlet rocker ok, valve opens with tool, pushrod nice and straight and ends look good. .................

Thus assuming collapsed lifter or busted cam lobe.  Built engine, super low ( but maybe a little hard,  kms. 

 

Common for LS engines?

[yel327]

Others here will be 100x more savvy on LS’s than me. I’ve owned three cars with them but never had to touch them. My mate had a VX type HSV GTS with low kM that chewed out a cam and lifters, I think it was weak springs that created the issue.

[Bigfella237]

The factory valvetrain in general is totally crap in pretty much all GEN IV engines. Valve springs, rocker trunnions and lifters especially.

 

Whoever built your engine (assuming it was done professionally) should have known this and used quality replacement parts, but who knows?

 

Unfortunately the heads have to come off to get to the lifters too.

 

They're also known for chewing out timing chain tensioners, oil pumps, and of course, piston skirts.

[RallyRed]

Who knows, but ta.
Engines come back and you assume they are as per...can't tell until you open them up.

[rexy]

Assuming you keep the right type of oil up to everything, are mechanically sympathetic and run a realistic rev limiter a factory LS should last an eternity. Most of the early LS problems were sorted out by the noughties.

[Oversteer]

Gen IV engine's are pretty damn tough, bar the usual quality control issues here and there they are the next level on a Gen3 in terms of power and reliability !

Edited by Oversteer, 17 August 2021 - 10:16 AM.

[Shiney005]

My young bloke wants to change the cam in his VE2 SS ute. It has the 6.0 litre L77, and with the car being a manual, it never came with the AFM (Displacement on demand), however I have been told that these motors still had the AFM lifters fitted at the factory? If so, I am assuming that these will need to be changed at the same time??

[RallyRed]

Not sure, I'm no expert Laurie, but in my conversation with various people this week re our LS2/L98, I am advised L98 and L77 are same. Later one with AFM/DOD.
I'm told a non DOD car can run a DOD engine, and just that the DOD will never work ( who cares?).
I guess that DOD roller injectors are just one more thing to go wrong i e sticky pin etc.
Others may confirm?

Edited by RallyRed, 20 August 2021 - 09:42 AM.

[Oversteer]

Yes the L77 was the DOD motor, has solenoids and different lifters, which are no good for performance work, so they need to go if you want a decent cam in there, pretty sure a lot of places sell a kit for the swap, cam lifetres etc to make it all work.

 

Pretty straight forward job, and if you shop around parts are cheap, google L77 DOD delete kit.

[Bigfella237]

The first 6.0L engines in Aussie Commodores were the L76, they had the DOD gear, but it wasn't ever active. The L76 was essentially an aluminum block variant of the LY6, but the Australian models didn't get the variable valve timing gear, and had an LS3-style intake manifold and a revised camshaft, which sacrificed top-end power but added low-down torque.

 

The L76 was then replaced by the L98, which did not have the DOD gear at all - I believe they said it was to save on production costs although I think there may already have been reliability issues with the DOD valvetrain.

 

Then the L77 was phased-in, on auto cars at first and eventually replaced the L98 altogether. All L77's had the DOD gear but it was just turned off in the ECU of manual trans cars.

 

The DOD system (or "AFM" as Holden called it) was active in automatic Holden vehicles from January 2009. AFM will automatically close the intake and exhaust valves in four of the eight cylinders (cylinder #s 1, 4, 6 & 7).

 

It does this by energising a series of solenoids located under the valley cover which change the flow in dedicated oil pressure galleries to allow the lifters on those cylinders to "collapse", thereby not opening the valves.

 

The upshot is, Laurie, that if you want to put a decent grind camshaft in it, you'll need to purchase a "DOD delete kit", which is basically a replacement valley cover that deletes the solenoids and re-routes the oil galleries.

 

The lifters you would replace with the camshaft anyway.

[yel327]

Don't they open one of the valves on the de-activated cylinders? So the engine is only moving a piston with no compression. That is how Ram does it I think.

[Shiney005]

The upshot is, Laurie, that if you want to put a decent grind camshaft in it, you'll need to purchase a "DOD delete kit", which is basically a replacement valley cover that deletes the solenoids and re-routes the oil galleries.

 

The lifters you would replace with the camshaft anyway.

Yep. I just had a google around and the "valley plate" needs to be replaced. Heads off too dammit.

[RallyRed]

yeah. PITA the way those lifters are trapped under the head.