matthew20061

iTrader: (4)

Not sure how this happened, a new L92 rocker arm is on order for a temporary fix to see if everything is going to be okay. I think it was just a freak problem. 1-2 Shift=6500 RPM, 2-3=6400. I installed the entire L92 top end about 800 miles ago and the truck has only seen very minor wide open throttle time. Two passes and just a couple runs on the street nothing else but just cruising around time. Two weeks ago I did a quick 1-2 shift and it wound out and ran awesome. Seemed to run fine afterward but last week I went to start it up and noticed a misfire and found this:

stock48

iTrader: (16)

I can't see very good on this phone but be sure and make sure the keepers are seated against the valve right.

silver-mod-o

iTrader: (15)

That **** will cause a misfire just about every time hopefully like you said, it's just a freak thing. Hope you get back on the road shortly

smokeshow

iTrader: (16)

Did you use new valve spring seats? I had a friend who put new springs on his GTO and didn't replace the seats, and was breaking springs and rockers all over the place.

Mangled03gmc

iTrader: (95)

Push rods the correct length?? That is alot of lift on the cam.. Possibly coil bind??

silver-mod-o

iTrader: (15)

.6teens is well within the limits of that spring... over .600 isnt a big deal really until you get over .650ish... then it gets a little more hairy.

iamkeniff

iTrader: (16)

Ouch...im scared now lol

matthew20061

iTrader: (4)

Everything was new including the seats.

Yes I believe the pushrods are the right length, I know another guy with the exact same cam and heads on a 6.0L and hes running the same ones and has not had any problems.

Gadgetized

iTrader: (9)

Always check PR length on any build, especially when there has been milling, decking, new cam, valves, seats, rockers, or head gasket. It is too easy to check, and then you know it is set up properly.

Is there a chunk missing out of the retainer? Are any rockers hitting the retainer? What does the tip of the valve look like when you wipe the oil off? There should be a uniform pattern on it. Are the tips of the rockers centered on the tip of the valve? Can you flip over the broken part, and take a pic of the foot (where the tip contacts the tip of the rocker) after you wipe the oil off? It is hard to tell from the pic, but are those offset rockers? Do not run it with the new part until you get this resolved, it will only cause more damage.

skeet

iTrader: (18)

that one retainer looks like it spun, the rocker scraping it? it'lldo it if the rocker isnt properly torque

i run a 621 lift now and have ran a 624 lift. that one retainer doesnt look like its seated properly.