squeeking VS ecotec roller rockers

[Immortality]

Most factory rockers have roller bearings in the trunnions, it doesnt make them roller rockers.

modern rockers have roller bearings in the trunnions, such as the ecotec/alloytec V6 models and gen III v8's. before then the standard friction style rockers were still used such as the buick V6 models, so up until 15 years ago, even holden continued with the standard friction style rockers on the 304 until they were phased out in 98

Bullshit

ouch, someone still a bit sore from the last V6 thread

 

[nalchlan]

youd think they wouldnt produce them at such a ratio if it pushes your valves too far onto the seals :/ and yeah i thought it could have been the push rods rubbing, i forgot to mention the front left hand pushrod looks like it rubs on either the gasket or part of the head...im not sure what. whats the best way to fix this? i put in the new pushrods that came with it..but i didnt check any markings on them so i dont know what they are..if youre still reading MACE what are the push rods the rockers came with? thanks to everyone for offering actual advice...and in regards to the roller rocker debate. in the diesel world (where i work) the roller rockers are roller tipped on the camshaft side...i guess the term is thrown around a bit with no one definition. i should have looked at the picture haha

 

[Brett_jjj]

Just because some rockers have needle roller bearings in the pivot,doesnt make them roller rockers,I remember years ago when everyone was fitting yella terra roller rockers to their red 6's etc,and even the car mags at the time ran reviews on yella terra roller rockers and heads,and the big deal was made over the roller at the tip,not the needle roller bearings used in the pivot.Yeah,the needle roller type are probably better than the old slide seat type,but it still not a true type of roller rocker without the roller at the tip..The roller at the tip apparently stops a hell of a lot of the friction and valvetrain vibrations that the normal solid tip ones generate,especially at high revs.A lot of engine builders found that they had less valvetrain failures when roller rockers were fitted.I remember reading that a lot of engine builders were very impressed with them.

 

[Andrew426]

modern rockers have roller bearings in the trunnions, such as the ecotec/alloytec V6 models and gen III v8's. before then the standard friction style rockers were still used such as the buick V6 models, so up until 15 years ago, even holden continued with the standard friction style rockers on the 304 until they were phased out in 98




ouch, someone still a bit sore from the last V6 thread

Car and truck manufacturers have been putting roller bearings in rocker trunnions for 30+ years, IMO holden came to the party pretty late.

I pulled the heads off a TL-11 leyland on monday that had rollers in the rocker trunnions, doesnt mean it was anything special. Still a POS.

 

[Immortality]

on the issue of roller tipped rockers, there were manufacturers that made rockers that only had a roller tip but still used the standard ball/seat friction type mount on the main pivot point. is that a true roller rocker?

also, if you compare the old pressed steel type rockers Vs the newer factor style roller trunnion rockers you will see that the newer rockers have a much smaller tip of parabolic design Vs the pressed steel style rocker which have a very wide contact point which leads to high side loadings on the valve stem and wear on the valve stem tips. the modern factory style rockers with parabolic tips are much better.

 

[soop]

I don't doubt your point about the Higher side loadings with the old style rockers. Mainly because I've no evidence to the contrary.
But as for wear, I've pulled apart engines with 400k on them and there's no visible sign of wear on the valve stem.

 

[Immortality]

maybe not on the valve stem, but plenty of wear in the guide in the head. this isn't so bad in stock applications because of the relatively small lift that most stock cams run, however if you were to run high lift camshafts with aggressive ramps and/or high ratio lifters the you would notice accelerated valve guide wear unless you went to the trouble of fitting bronze valve guides. i just stripped a pair of buick heads, with the old style rockers, valves won't pull out unless you clean the stem tips with a stone to get rid of the burr on the edge from the way the rocker works over the valve stem tip.

 

[MACE]

Amazing how this topic crops up every so often. Makes my job easier as all I have to do is copy and past what I written over the years

Yes our rockers are based of the factory items, which are a roller rocker as they do run a rolling element bearing in the trunnion/pivot. We don't make the rules in this regard and it’s the reason why they are classed as a roller rocker as there is a rolling element bearing in which the rocker "rocker's" about. For arguments sake, if the rocker ran a plain bearing in the trunnion/pivot but a roller tip on the end, it could still technically not be classed as a roller rocker, as the location of the roller bearing is not causing rocking

Case in point crane cam rocker arm in the link below, which runs a roller tip but a plain bearing

Crane Cams Rocker Arms - Circle Track Magazine

An EXCELLENT competition rocker BUT can it be classed as a roller rocker? Reading the article makes no mention that it is, I’m guessing because of the bearing style it’s running in the trunnion…

So people may argue here that it is or it isn’t a roller rocker, the fact that it uses a rolling element bearing on the tip to “reduce” friction I can understand why people would. I’ve fallen in to this school of though of late I mean lets face a roller bearing in a rocker arm gives you a roller rockers whether it’s a “true” roller rocker or not.

In all fairness what is a “true” rocker arm anyway? I mean 99.99% of the roller rockers on the market are still relying on effectively a plain bearing between the pushrod and pushrod cup? Yes, depending on the rocker arm design a bearing can be put on the end of a push rod cup to make it a “true” roller bearing, it’s just too hard…

Anyhoo we’ve never hidden the fact they they’re not roller tipped items, as can be clearly seen by our adverting pics and the feedback I’ve personally given over the years on numerous forums and emails etc.

As for the purpose of not having having a roller tipped rocker, two main reasons,

• they reduce the amount of un sprung mass the valve spring has to control given the reduced valve tip weight reducing chances of valve float. Meaning valve springs are less likely to be changed to control increased mass/inertia. In bolt on applications where people are looking at ease of installation this is a big plus.
  
• The effective ratio of a non roller tipped item increases while a roller tipped item decreases. Basically you get more lift out of a non roller tipped rocker then you would a roller tipped one based on the same static ratio, meaning more power per given static ratio. In bolt on applications where people are looking for power this is perfect.

Don’t get me wrong I have no problem with recommending roller tipped rockers in builds that run highly aggressive cams or very stiff springs as the serve a valuable purpose in certain applications. However to believe that roller tipped rockers are the messiah when it comes to saving guides or valve train stability on ecotecs I can’t hugely agree, two main reason why

Firstly the geometry of the fixed tipped ecotec rocker has more of a tendency to rock over the top of the valve stem then to drag like earlier rocker designs meaning that the force component perpendicular to the side of the valve steam is very minimal. Long story short there is less of a bending moment put on the valve stem reducing both friction forces at the top and radial loading on the valve guide of the bat. Sure rolled tipped rockers have less in this regard but…

The second reason is that the force distributed across the valve retainer, which contact the valve spring, induces a bending moment regardless of rocker type radial loading of the guides as can be seen from the valve stem bouncing around from side to side, even with a roller tipped rocker, from the link below.

YouTube - Short Valve Float Movie

Given by how much the valve stem deflects from side to side this force is definitely not an insignificant one!

The way to reduce this component though would be to keep the top of the guide as close as possible to the retainer, conical type valve spring with the smallest mirror diameter as possible accompanied by appropriate retainers.

Hope this clears a few things up for people

Cheers,
Steve

 

[MACE]

on p-plates so i cant get a v8..or id have one, and dont wanna get a cam because i cant be bothered getting a double row timing chain.

haha yeah i know some vs drivers too..but it wasnt bouncin off the limiter it was just a bit of gravel, it was just a spin for about 10 metres.

never heard of it happening before mace? i dont want to send them back i just want to find the squeek, and yeah i got the new push rods and theyre in. i made sure they were seated right, one thing i didnt do was rotate the engine to a certain so its not compressing the spring? and ive looked them over theyre ok, not meaning to say your rockers are bad... another thing i thought is if the guy who owned my car beforehand got a different head gasket and its scraping on it?

If it’s a genuine VS engine, with only aftermarket head gaskets then that may be your problem. The clearance the overhung gasket you could try and break it off with a set of long nose pliers. It would be unlikely that the skinnier supplied pushrods would be rubbing otherwise. As for sending them back up am happy to pay for postage.

youd think they wouldnt produce them at such a ratio if it pushes your valves too far onto the seals :/ and yeah i thought it could have been the push rods rubbing, i forgot to mention the front left hand pushrod looks like it rubs on either the gasket or part of the head...im not sure what. whats the best way to fix this? i put in the new pushrods that came with it..but i didnt check any markings on them so i dont know what they are..if youre still reading MACE what are the push rods the rockers came with? thanks to everyone for offering actual advice...and in regards to the roller rocker debate. in the diesel world (where i work) the roller rockers are roller tipped on the camshaft side...i guess the term is thrown around a bit with no one definition. i should have looked at the picture haha

What delcowizard has mentioned would not be the case! If it was it would be making more of a ticking sound not a squeaking one. As for trying to help you out a quick phone call or email would have it sorted out in about 5 min. I mentioned this to you in this thread on the 8th, when you wrote the above on the 11th

I'll be honest with your it's the first time I've ever come across this problem based on the many sets we've sold

If the rockers are a fault then it's no big deal as they come with a lifetime warranty. Shoot us an email or give us a call. Were you supplied with different push rods?

Cheers,
Steve

If I had not done a search for “MACE” on the site I never would have know of the problem, but I took the time out to approach you of your problem.

On this note if people are really concerned to get an issue with one of our products sorted all they need to do is email, PM, call or post in our section of the forum. I’m no minder reader (if I was I would be doing that for a living LOL) if people have a problem they need to let us know directly. I genuinely enjoy helping people, which is at the expense of my own time away from my family, if people let us know.

Cheers,
Steve
1300 466 223
[email protected]

 

[soop]

So what does that count as?