dyno'ed today, and the car was very low. 465ish. did a compression test and they are all ok. one was in fact pretty high, and on that cylinder, then exhaust rocker was broken. as some of you may recall, an intake rocker failed on me a bit ago. all intake rockers were replaced, as those are offset and a more aggressive lobe.

watch your ls7 rockers guys!

time for the harland sharp conversion. that or jesels, eeks. $$$

 

geez, that really concerns me...guess I'm going to have them rebuilt and reinstalled while in away overseas! Can't believe that....how many miles thus far? I've put on 1200 miles already...

Adrian

 

Have you considered that the failures might be due to you BIG *** VALVE SPRINGS!!!

Anyways, the springs you are using are beefy mothers, so they will put a ton more stress on the rockers, obviously. Does Harland rebuild LS7 rockers?

 

Harland Sharpe conversions are the shiznit Good question on if Harland Sharpe would do LS7 rockers... I don't see why not... isn't the trunion area the same as the LS1 style?

Bill

 

Harland Sharp confirmed on friday they can do the LS7 rockers.

My springs aren't that crazy, IMO. My buddys AFR 205's with Comp 921's have more pressure than mine.

I have about 2200 miles on the motor. First rocker let go about 2000. 2nd at 2200

 

Do you have the conversions? If so, could you take a picture? I'd like to see them.

 

Bummer about the broken rocker Greg. Keep us posted on the Harland Sharp rebuilds if you go that route.

Richard

 

Are you the only one breaking them Greg? There has to be a harmonics issue with your setup thats rattling them apart. I have dozens of packages out there from 540-620 rwhp and not one reported rocker failure in 10 months, including 2 race cars.

 

What length pushrods are you running? Is it an LS1 block?

 

I do not have pics... best description is a beefy trunion with external clips. I know of a place that has the rockers but they are not a sponsor anymore. I would call some of the forum vendors and ask. Shouldn't take you too long to locate them...

Bill

 

I have 2 sets of the stock rocker with the harland sharp mod. One on my LS6 and a set for my buddies ls7 we are building. They do it. Call Nate@ Nasty performance. Its about $260 for the mod. I can get you guys a pic of them Tuesday. Since I am @ work now and wont be back @ the shop untill then.

 

I am running a resleeved 5.3l alum block. I dont recall the pushrod length exactly. I'll have to check.

 

Cool, those are mine!

Do the LS7 rockers spill their bearings too when they go?

 

Yes, they do

 

Yes they do. Thats why we did my buddies and those were the only pics I could find on the net. Hench why I said tuesday I would post the pics of the LS7's with the mod on them.

 

I have seen comments about the HS rebuild of GM rockers before but have never really known what they do or what the advantage of the rebuild is.

I had been told somewhere, it may have been a tuner, that GM had needle bearing problems with the earlier rockers but had corrected it in later years. True or not? Then again is this something that only shows itself with higher spring pressures?

What does HS do to the stock rockers and how does it help.

 

http://www.harlandsharp.com/bolton3.htm

go to the ls1 rocker arm conversion kit for details.

 

Thanks for the link.

So apparently is is a problem introduced by accelerated lift rates, higher lift and high spring pressures. I wonder where the limits of the stock units are?

 

hi guys,

the problem i had was that the tip titanium of the intake valves where the rockers are in contact wear out, and i mean wear out fast like in 2 hours of operation. exhaust is fine. any ideas.

 

are you using a lash cap? the ti intake valves are not hardened, and will wear out very quick. you MUST use a lash cap.