Guys I am looking to see how many guys have had failures and how many have had no problem. There are alot of threads about failures that has me nervous. Although no one posts up when they have a good working set or how long they have had them. Looking for a little help as I have a set from 08 and have been running with no issue. I am about to change my set up and the. Vendor I purchased my heads from recommended not running them and going back to the stockers.

 

I've been using them for years and never have had any go bad on me. It's all about setting up right geometry on them.

 

Also looking for some input on the rockers.

 

OP, are you running bronze valve guides? if not, I wouldn't think that there's any real advantage to running roller rockers. if you're worried about it, swap back to stockers.

this. you can't just throw a high lift / aggressive ramp rate cam, extreme pressure springs, and flimsy 7.400 push rods in there and call it a day. in addition to the overall setup and component matching, initial setup is critical as well - checking wiper pattern and shimming if necessary, rocker arm clearances, setting the correct push rod length, verifying your springs have the appropriate clearance from coilbind at peak lift...etc etc.

the older revisions were designed in the early 2000's - long before the cams of today were common (lifts > .600", aggressive lobe shapes). the springs required to control a cam like that have too much open pressure for the early design - it's a case where the hobby outgrew the initial design of the rockers.

since that time they've been redesigned to support some of the additional loading - what is known as "Revision 3" - I have not heard of or seen a reported failure of these yet. I wouldn't exceed ~420lb open pressure with them (there's no real reason to exceed that anyway on 95% of setups), though the design is supposedly capable of handling up to 500lb open pressure. For longevity I would also be very selective with what lobes you're running with them as well.

For reference (borrowed from another thread):

- According to YT AUS, the after 2010 upgraded new and last model (for now) Ultralite's are stamped ON THE RIGHT DIDE

- The before 2010 model (the one's breaking more than usual...) are stamped IN THE CENTER

- The before 2007 model are stamped one are stamped ON THE LEFT SIDE.

Rev 3. Note the additional meat surrounding the trunion area.


Non-rev 3

 

I have about 3k on mine. Center stamp.
Carefully set up, wipe pattern correct. Good pushrods. AFR heads, the springs are right at 400lbs open.

To be honest, I'm waiting for one to break. I believe it's just the number of cycles, and a matter of time.

If there is a better solution out there, short of the high dollar jessel setup, that fits under the stock covers, I'm all ears.

If, I could change the heads to iron guides, I'd do that, but don't think it's an option.

Ron

 

I'm really curious as to why no one has developed a lightweight steel 1.7 roller rocker (that don't cost a fortune). an open spot in the market that would address the fatigue / weight issues inherent to aluminum rollers. If that were an option and the price was comparable I'd be running those, no doubt about it.

 

There was a thread not too long ago where someone had the newest model and had a failure.

 

i bought a set in late 2009. they last almost a year before one broke. Yella sent me an entire new set to my door expedited from Aussieland and now almost 3 years running on them with no issues yet (not on wood). honestly if I had to do it all over again I would get stock rocker arms with the Trunnion kit.

But hey if one breaks let me know and I will send you one of the 15 Yella Terra's sitting in a box in my garage!

 

Was that the guy running the 1.8's?

Unrelated....does anyone know anything about these rockers? http://www.prwonlinestore.com/stainl...t-0234611.aspx

 

I know a lot of the problem is guys probably running too much cam and not checking the geometry or open pressures. Above its stated not to run over 320 lbs open pressure. Half of the valve spring companies out there are over this with their dual kits?????? I know there are a couple that are not just wondering why so many have such high open pressures? I will have too pull my valve covers and see what version I have. Most of these break and they don't cause much damage and people get lucky although I seen a thread on here last week were the roller tip of the rocker broke off and destroyed the cylinder head and piston. People blamed the rocker but it seemed like the valve stuck or bad set up. Just looking to see how many people are running them with no issues. Thanks guys

 

I'm not sure. I just remember reading it.

 

I have used Yella Terra rocker arms on a bunch of builds on several different applications. Big block chevy small block, ls1, ls3 and ls7. I have never had any issues with them. Of course when I plan a build, I use a combination of parts that will work together. Also, Yella Terra has different models for different applications to match with cams and spring combos. Not a lot of people know that they have the ultralites for the light build, Yella Terras and the Platinum series for the high spring pressures on the more serious builds. Most everyone has been using the Ultralites. If you are going to step up the spring pressures and aggressiveness of the build then you need to step up to Yella Terra's Platinum series rocker arm. Use the right rocker arm for for the right application. Also, you need to make sure your geometry is correct. That is the only way to ensure the longevity of your build.

 

PN# 6645 - Yella Terra non-adjustable ultralites, 1.7 ratio

PN# 6638 - Yella Terra adjustable ultaralites, 1.7 ratio

PN# 6640 - Platinum series, adjustable race series, 1.7 ratio

At what point would you say the platinums are necessary? From the info on the website it seems that those are for solid roller setups.

 

Been running mine since 2008 without issue. As stated above, the setup is a key aspect of running any rocker, including stock. The beauty of the YT's is the narrow wipe that can be attained when set up correctly. Improper setup will not only accelerate guide wear, but loads within the rocker. I set up my wipe pattern on the work bench and spent several hours doing to to minimize the width. In the end I got it down to 0.045".

The new ones are even stronger.

 

The Platinum series are not just for solid roller set ups. You see most of the info leaning that way because they are good for up to 1000lbs of open pressure. Yella Terra recommends the use of the Platinum series on any build using 450lbs plus of open spring pressure.

 

There is a set upjust like you described...they are called GM stock rocker arms...if you want an upgrade do the trunion modification to them...I've been using stock rockers for over 260,000 miles and they work like a champ..

 

Installed TFS 215 heads & #6645 1.7 Yella Terra Ultra Light rockers back in March 2009. Cam was a LG G5X3 114. So far I have about 15000 miles on the Yella Terra rockers. And the TFS springs have 450 lbs open pressure.

I just installed a EPS 234/242/.600/.615/117+2 camshaft, and changed the valve springs to Brian Tooley platinum springs/titanium retainers. They have 395 lbs open pressure and his retainers weigh 9 grams vs 11 grams of the TFS retainers that also are titanium.

Also I've never used the so called new car formula oil. Used 15w50 Mobile 1 until I switched to 10w30 Joe Gibbs 2 years ago.

Russ Kemp