i think the pushrod cup is secondary damage, was the poly lock tight or loose
Going to make an assumption that these were not new to start with? I would take a close look at the rocker stud too...
GT
brand new set of pro-comps.....studs look good.
geometry looks good. roller is centered on the valve stem at all times...no binding.
pro-comps
when priming the motor....i got good flow to all 16 rockers
no obvious weird wear marks...what should i look for?
And there's your answer. Pro Comp is cheap Chinese junk.
brand new set of pro-comps....
I know this sounds stupid but it looks like it was bolted down with the inner sleeve up side down. They only go on one way. Also. I would step up to shaft mount rockers. You will pick up around 10 hp. eliminates play from side to side you will get a tad more lift. you also don't have to run stud girdles with them and personally their all around better. Ill never go back to em after having the shaft mount ones.If it wasn't a 1k investment on a cruiser motor it would be the best route.
Also clay smith has the strongest studs Ive ever seen. way stronger than arp. check them out there bad ass.
If it wasn't a 1k investment on a cruiser motor it would be the best route.
Shaft mount IS the way to go though.
-beerjet-
YOU START OUT WITH CHEEP JUNK YOU END UP WITH JUNK
THEN YOU ANT DOING SOMTHING WRIGHT ?
CHEAP AINT GOOD AND GOOD AINT CHEAP
I agree , but I think these rockers are on a stock-ish cruiser motor .
Yea but a good set of roller rockers is about 500-900 $ plus another 200 for girdles puts you at, or over the 1k mark
I would step up to shaft mount rockers. You will pick up around 10 hp. eliminates play from side to side you will get a tad more lift.In and of itself, simply switching to shaft mount rocker arms over stud mounted rocker arms will neither garantee more lift at the valve nor will it garantee more horsepower.
The pushrod cups give the impression that there is a poor heat treat on the rocker arm bodies, but this presumption cannot be made only by looking at pictures. Poor valve train geometry can also cause rocker arm failure. By the way, technically speaking where a roller rides on the tip of the valve has nothing to do with geometry nor is using the "roller-tip-in-the-middle-of-the-valve" technique during vavle train setup a garantee that correct valve train geometry will be established (although given the fact that most rocker arm manufacturers design a body for a specific valve train will usually enable practicing that method and gettin geometry in the ballpark). :-\
Trying to use cheapo parts in an exotic engine build will often end up costing you more money than had you used properly suited parts in the first place.
LO...With all do respect.....I disagree with you...The rocker MUST ride in the middle of the valve tip...Please explain..It is ..ballpark :sly:
LO...With all due respect.....I disagree with you...The rocker MUST ride in the middle of the valve tip...It has been my observation that this is a common misconception, that the roller "MUST" ride in the middle of the valve. To most people it seems to make better sense intuitively that the roller tip must be centered on the tip of the valve. That is not the case. But....you first ;D : Why do you think the roller "MUST" ride on the middle of the valve tip?
Please explain.."It is ..ballpark"Truly sorry, I type fast and move from forum-to-forum, sometimes with an inadequate proof-read....I'll try to re-write the statement in a more easily readable context:
I know this sounds stupid but it looks like it was bolted down with the inner sleeve up side down. They only go on one way.
i had another one fail....didnt break like the one pictured, but had the cup wear like the other.
i will be putting a new set of rockers on order today. in the mean time....what do i need to do to check my geometry so i know its not the setup, but cheap parts and im not going to run into this problem again on a more expensive set of rockers.
i had another one fail....didnt break like the one pictured, but had the cup wear like the other.
i will be putting a new set of rockers on order today. in the mean time....what do i need to do to check my geometry so i know its not the setup, but cheap parts and im not going to run into this problem again on a more expensive set of rockers.
B, no rocker is that "cheap" that it comes apart in a couple hours. You have another problem. Check the stuff Glen outlined and you'll prolly find some bind somewhere
Are these the same rockers that have been on this motor for X number of years? Or were they part of the new valve train?
thats the plan...i will be going through the valve train when i drop on the new rockers...checking the things glen outlined. better safe then sorry...dont want to junk another set of rockers.
what do you guys think about the comp cams ultra golds? http://www.summitracing.com/parts/CCA-19021-16/
In and of itself, simply switching to shaft mount rocker arms over stud mounted rocker arms will neither garantee more lift at the valve nor will it garantee more horsepower.
LO
Sorry bud but your wrong. Here's the proof.
I read the attachment/advertisement. Twice. I had to read it twice because, 1) I didn't see anything written in the advertisement about horsepower gains that applied specifically to shaft rockers in general, and, 2) the claims that I did see about hp gains were not rocker shaft specific but were actually design related...design specs which can be applied to any roller rocker, be it a shaft system, a stand system, or even a stud system.
Sorry bud but your wrong. Here's the proof.
Hello Lakes..... if ya want my opinion ...I will give ya it... ;DAnd there-in lies the most common misconception about why the roller tip must be kept around the middle of the valve....because "the valve guides will prematurely wear if the roller tip is on the outer (or inner) edge."
This process is essential to prevent v/stem wear among other issues as we both know.
Your turn Boss ;)
the application here in discussion is a pretty much stock bottom end hardin marine bbc with 990 heads that were gone through and valves/springs setup for the cam that came with it (solid flat cam). i set the valve lash to the cam card (.021) and the boat doesnt go over 4k @ 62mph
this isnt a full blown race application....its just a lake boat motor in a day cruiser.
has anyone ever heard of "miller mid-lift"We are the west coast distributor for Miller Rockers.
so with that being said (the application in question)
do i really need to spend $270 on a set of full blown race roller rockers?
or can i go with some comp cams magnum rockers for $140
http://www.summitracing.com/parts/CCA-1411-16/
battle of the builers eh? this is starting to look like a hotboat thread.. boys lets tone it down and keep this a freindly forum.
Brad, FWIW those are the exact rockers I have in White Trash, been through a catastrophic cam failure (due to a cam thrust problem), three different builds and still work like new, this 468 runs to 5200 RPM and never even farts funny......BTW, I bought them at a swap meet for $50.... :screwy:
You cannot go wrong IMHO..
Sorry dad.. ;D
GT
I just got home, I cannot make the string test work for me...As the arm goes up/down, the string moves too and fro....The valve stem is not physically represented in this excercise, it must be imagined. The string represents the diameter of the roller tip (dia = from the fist [axle] to the weight at end of the string [roller diameter]), which moves slightly to-and-fro across the (imaginary) tip of the stem that it rests upon. Also in this excercise, we are using gravity (the string being tensioned by the weight on the end) to represent the linear force that pushes down on the (imaginary) valve stem as the rocker arm moves through its radial sweep. Because of the roller tip, the force exerted on the tip of the valve stem stays linear and in-line with the valve stem. With a traditional shoe rocker there is just 1 pivot point (where the pad contacts the stem tip), but with the roller tip there are 2 pivot points ( the roller axle and where the roller's diameter contacts the stem tip).
The valve does not do that...(intentionally anyways) what am I missing? :-\
I was told the roller tips were for greater valve tip contact that never hits the same place twice.This is certainly a benefit of a roller tipped rocker arm. I wouldn't say that it is the primary reason for it's application/integration into a rocker arm.
I am curious to find out where all this fits in with a 350 HP cruiser motor though... :sly:I didn't know we were still on this thread's topic. :D
I use Comps roller tipped steel rockers, I will explain why...All fine. Also, see my reply to Brad's inquiry about trunnion ball roller tipped rocker arms.
I do not run stud girdles in my toy motors, too much of a ball grinder to set up, too damn expensive, unnecessary and don't forget overkill...I run ball hinged roller tips because they are cheap, they work, they take mere minutes to verify setup and will work even if you bend a rocker stud...Most importantly, the dyno will not be able to tell you if they are there or not (under 5K)...The difference was like 2 HP (got more gain than that just switching over to synthetic oils of a lighter weight). :sly:
To add further, there is a little less valve train harmonics in a ball hinge type rocker because of the added contact within the rocker...These can be minimal at much higher RPM with full rollers, which is where they (full rollers) really start to shine from a performance perspective...I can't reply with much personal experience in this area, but my speculation is that there is always some level of valve train harmonics in any vavle train but that the combination of parts/rpm/etc make up where the harmonics manifest, not if....regardless of rocker arm type used.
so with that being said (the application in question)Generally speaking, most of the standard ball-trunnion (aka ball fulcrum) rocker arms (whether roller-tipped or shoe-tipped) aren't intended be used for valve lifts beyond about 0.550". While the quality ball-trunnion rocker arm bodies might be strong enough to handle much more lift and spring pressures (since they are usually made from steel), the nature of ball fulcrum rockers by their design limit applications to ~0.550" lift max. More than that and you may begin to see premature wear of the fulcrum balls (because of the associated spring pressures).
do i really need to spend $270 on a set of full blown race roller rockers?
or can i go with some comp cams magnum rockers for $140
http://www.summitracing.com/parts/CCA-1411-16/
battle of the builers eh? this is starting to look like a hotboat thread.. boys lets tone it down and keep this a freindly forum.Battle??? Tone it down??? This is a friendly discussion, not an arguement. If you are a moderator then I am laughing at your post right now. And I'm confused by it.
Crap than link didn't work rite Ill copy and paste.Enough already with all the copy & paste; we all read the internet too, you know.
Battle??? Tone it down??? This is a friendly discussion, not an arguement. If you are a moderator then I am laughing at your post right now. And I'm confused by it.
The valve stem is not physically represented in this excercise, it must be imagined. The string represents the diameter of the roller tip (dia = from the fist [axle] to the weight at end of the string [roller diameter]), which moves slightly to-and-fro across the (imaginary) tip of the stem that it rests upon. Also in this excercise, we are using gravity (the string being tensioned by the weight on the end) to represent the linear force that pushes down on the (imaginary) valve stem as the rocker arm moves through its radial sweep. Because of the roller tip, the force exerted on the tip of the valve stem stays linear and in-line with the valve stem. With a traditional shoe rocker there is just 1 pivot point (where the pad contacts the stem tip), but with the roller tip there are 2 pivot points ( the roller axle and where the roller's diameter contacts the stem tip).
Thanks LO, been working like a dog lately an could not get my head wrapped around that...looking like a dumbass with a bunch of string and shit everywhere in the living room...Thanks for the visual, I am laughing so hard over here. :D
GT
Thanks for the visual, I am laughing so hard over here. :D
p.s.: "Hey Moe! Watch me simulate rocker arm travel with a big washer and a spool of twine! Nyuck! Nyuck! Nyuck!" ;D