WARNING LS3 Recall about to happen

[Immortality]

I'm gonna leave this here

 

[426Cuda]

Well the stock shocking steel rocker with friction tip is 8.2 grams and the ultralite roller tip I have as shown above is 7.8 grams.
The max spring pressure is 400 pounds, which is fine, you know for street legal sub nitrous sort of stuff!
The engine builder who recommended these services more than a dozen LS3 engines to race spec every couple of weeks.
Like I said, more speed, better lubrication, stronger, safer, less friction, less noise.
At least do the springs and pushrods at same time mate, you know you want to!

Are you sure the stock ones are pressed steel? I'm no machinist or metallurgist, but these look cast to me.

I also highly doubt a stock rocker is just 8.2grams. That's ~ 122 rockers : kg! It's an importa t point, because weight of roller rockers is a big downside compared to stock. Can you check your source on this one?
Like GVMSS said, everything I came across online said stock rockers were best, unless going ballistic with cam specs or revs etc. Mainly due to them being lighter, and sufficiently strong. Apparently the inertia is less too, as very light at the tip. So less of a drain on power, compared to roller rockers.
As I said in my other post. I'm very interested in the rockers you're using mate. But only if they're lighter than the stock arms, which are mated to the lightweight valves. Otherwise it's probably an expensive urge overkill. Stronger, but, heavier and greater inertia = less power (all other things equal). Mind you, I reckon the change in power either way would only ever be usefull at a dyno comp or in competition racing. Coz it wouldn't be much. I could be wrong though...

 

[revster]

Having the rockers replaced today, just wondering if the engine oil is replaced during the work. Car has done 5700km mostly country driving and just wondering if it would be wise to have the oil changed while being serviced.

AS Cuda said no, no oil is lost.

 

[426Cuda]

I should say for the benefit of most people who didn’t know what a rocker arm was before this recall, that switching up to a lighter roller rocker arm vs stock will give you minimum 20 horsepower, cooler running and less fuel consumption from the frictional benefit alone with stock tune. Greater potential to support tuning.
There are no downsides just a great opportunity if you want a set-and-forget way to ensure operational longevity and add efficiency.
Versus money spent on headers and exhaust or CAI, swapping rockers enables a genuine bolt-on power increase to the stock tune.
Apart from changing to flex fuel, the next simplest way to add significant volumetric flow is to up-spec the rocker arms to increase valve lift. To accomodate the change you need better valve springs and shorter pushrods (shot peened, nitrided beehives and chromemoly rods are best).
This uprated upper valvetrain works with the LS3 cam and hollow intake valve to safely increase the rpm, so with literally dropping in springs and rods with the rocker swap you will see minimum 25 kw, possibly much more with FBO and a tune.
All reversible, personally recommend after 200,000 miles with this simple upgrade.

Sounds good. I'm very interested.
Can you post up the brand etc of the rockers, springs and pushrods please.
Also, ballpark cost of the parts. Always a factor unfortunately.
I'll be getting my stock rockers replaced, as I want a full set of good ones to keep. But, will upgrade to full roller rockers, springs and pushrods when I get the cam installed. I'd rather go with something proven, like yours, rather than rely on the workshops advice and supplier bias.

 

[monstar]

Are you sure the stock ones are pressed steel? I'm no machinist or metallurgist, but these look cast to me.
View attachment 197034

Chi-co-ree Auto Cat! Cast for sure (and a bit wonky going by that pic), weird that they are often called pressed steel. But however manufactured, they are heavy, cumbersome, prone to stress failure, badly mounted for NVH and... the needle bearings are cageless.

 

[426Cuda]

Chi-co-ree Auto Cat! Cast for sure (and a bit wonky going by that pic), weird that they are often called pressed steel. But however manufactured, they are heavy, cumbersome, prone to stress failure, badly mounted for NVH and... the needle bearings are cageless.

Thanks Motormouse. See my edited post re weight please.

 

[426Cuda]

I'm gonna leave this here

Very interesting. Thanks.
So, while not an LS3, the comparison proved that the stock rocker (pressed steel non needle roller trunion), made more power than all the standard ratio non oem rockers. The only one that made more power was a higher ration 1.6:1. Even then, it was only able to do this due to other upgrades to stock, including heads with a greater cfm capacity than stock.
This attests to other stuff I've read re stock LS3 rockers (cast, with capped needle roller bearings), ergo the stockies make more power than same ration roller rockers. They may also add to longevity (i.e. less wear over time)and or reliability (i.e. less prone to causing other valve train component failure) of other parts e.g. cam lobes, lifters, push rods, springs, valve tips, faces and seats, as they are lighter and have less interia? Sometimes upgrading just one component, even if better than stock, can add to the risk of premature wear or sudden failure of other components. Particularly at high revs.
As, I said in my other posts, I'm interested in upgrading to the right higher ratio roller rockers, springs etc. But, only with a cam install. I'm not convinced of any tangible benefits over stock, with the same ratio and other stock components. The opposite in fact, i.e I think the cons outweigh the pros.
I'm happy to be proven wrong in my assessment, based on limited past experience, and current research.
Thoughts?

 

[monstar]

Sounds good. I'm very interested.
Can you post up the brand etc of the rockers, springs and pushrods please.
Also, ballpark cost of the parts. Always a factor unfortunately.
I'll be getting my stock rockers replaced, as I want a full set of good ones to keep. But, will upgrade to full roller rockers, springs and pushrods when I get the cam installed. I'd rather go with something proven, like yours, rather than rely on the workshops advice and supplier bias.

This is what I settled on, there are other combos for sure.
Rockers
Yella Terra (Whipple) ~$950
Sold overseas under many brand arrangements, Aussie Yella Terra is at the top of its game.

Stock rocker ratio geometry 1.7:1 is what most cams up to Gen IV (except the LS7) have used. Yella Terra PN YT6667.
LS7, Gen V and later engines use 1.8:1 to eliminate the inevitable cam face / lifter roller wear of LS builds, an alternative to achieve >0.550" lift with control and lower friction vs previously small base circle and aggressive cam lobe ramp. Yella Terra PN YT6668.
I kept AFM with revised lifters from the Gen V, so the base circle of the AFM cam is larger than most Gen IV, meaning lobe lift is just 0.300". So with AFM cams the standard 1.7:1 rockers (0.300" x 1.7) give 0.510" lift at valve, OK from an old school standpoint but not ideal for performance. 1.8 gives 0.540", and 1.85:1 (actually 1.865) gives 0.556" lift (bit more than LS3) with the later AFM cams. Yella Terra PN 6685.
There is a bit to explain the other main benefit - being increased cam size - per the time/area duration of the valve opening. Suffice it to say the start and end points of the opening (time) are of course the same duration but increased acceleration and extent of the valve opening (area) is increased which affects the effective time/area duration like an extra one degree duration per 0.5 increase in ratio.
So with 1.8rr Stock LS3 cam spec effectively becomes 206/213 117.5-2.5 LSA 0.583"/0.556" lift. Which is bloody great.

Springs
Peterson American Corporation (PAC Racing Springs) ~$400 with locks and retainers
The shortlist is PAC 1211x, 1511x, 1219, 1519 and Comp Cams 26915. The PAC 12xx series is a cheaper less treated version of the 15xx series. this is my worksheet:
View media item 436I also have Ferrea hollow stainless valves and so I chose PAC 1511x shot peened nitrided race springs with hardened steel valve locks / collets & Manley chromoly retainers.
View media item 250

Pushrods
Manley LS Chromoly ~$200
It's advisable to check pushrod length and replace with hardened lighter rods with less diameter. My geometry is different in order to get a raised compression and stuff so I went with above after getting sized properly.
View media item 437
Then the labour charge for (less than) five hours, ranges $500 to $900.

 

[monstar]

Very interesting. Thanks.
So, while not an LS3, the comparison proved that the stock rocker (pressed steel non needle roller trunion), made more power than all the standard ratio non oem rockers. The only one that made more power was a higher ration 1.6:1. Even then, it was only able to do this due to other upgrades to stock, including heads with a greater cfm capacity than stock.
This attests to other stuff I've read re stock LS3 rockers (cast, with capped needle roller bearings), ergo the stockies make more power than same ration roller rockers. They may also add to longevity (i.e. less wear over time)and or reliability (i.e. less prone to causing other valve train component failure) of other parts e.g. cam lobes, lifters, push rods, springs, valve tips, faces and seats, as they are lighter and have less interia? Sometimes upgrading just one component, even if better than stock, can add to the risk of premature wear or sudden failure of other components. Particularly at high revs.
As, I said in my other posts, I'm interested in upgrading to the right higher ratio roller rockers, springs etc. But, only with a cam install. I'm not convinced of any tangible benefits over stock, with the same ratio and other stock components. The opposite in fact, i.e I think the cons outweigh the pros.
I'm happy to be proven wrong in my assessment, based on limited past experience, and current research.
Thoughts?

I actually resent that I pay to get this crock of crap show as part of my Motor Trend video subscription, cheap LOLs after a few drinks watching the half-arsed backyard bullshit spewing forth from most of them.
The engine is thirty years old, the results are always shocking, never as up-to-date as using LS-specific components, stuck at the back of the class mired in Old Skool.
As a matter of course I speak to engine masters (not these tosspots but pro LS engineers and race scrutineers at the top of their game) on a regular basis and this fluff is... sensationalist at best.
Anyways, only trying to help with some real world experience over seven years and 200k miles of reasonably constant research and development, but of course if you find a serial nutbag video segment which on the face of it says stick with the stock stuff then hells yeah, cheap way forward aye!
PS these guys also proved that the size and shape of header design doesn't matter at all either.

 

[Immortality]

Very interesting. Thanks.
So, while not an LS3, the comparison proved that the stock rocker (pressed steel non needle roller trunion), made more power than all the standard ratio non oem rockers. The only one that made more power was a higher ration 1.6:1. Even then, it was only able to do this due to other upgrades to stock, including heads with a greater cfm capacity than stock.
This attests to other stuff I've read re stock LS3 rockers (cast, with capped needle roller bearings), ergo the stockies make more power than same ration roller rockers. They may also add to longevity (i.e. less wear over time)and or reliability (i.e. less prone to causing other valve train component failure) of other parts e.g. cam lobes, lifters, push rods, springs, valve tips, faces and seats, as they are lighter and have less interia? Sometimes upgrading just one component, even if better than stock, can add to the risk of premature wear or sudden failure of other components. Particularly at high revs.
As, I said in my other posts, I'm interested in upgrading to the right higher ratio roller rockers, springs etc. But, only with a cam install. I'm not convinced of any tangible benefits over stock, with the same ratio and other stock components. The opposite in fact, i.e I think the cons outweigh the pros.
I'm happy to be proven wrong in my assessment, based on limited past experience, and current research.
Thoughts?

Yep, that test kinda debunks the myths about roller rockers been more efficient because they reduce friction. The only reason the extra power was made was because the ratio increase.

It really was interesting to see the stock ratio roller rocker loose power at the top end compared to the standard pressed steel rocker.

I have no doubt that full roller rockers improve longevity of parts and it's very interesting to see that GM have gone with a roller bearing in the trunnion put maintained the standard friction tip, you have to wonder if this was done to keep the rocker tip weight to a minimum? Then there is also the argument of how a roller tip Vs friction tip and how each effects lift. This was debated quiet vigorously around the MACE high ratio roller rockers and what constitutes a roller rocker....