New Engine Running Bad Please Help!

[tatersalad25]

Ok so I just got done swapping in my 6.0 and fired it up today, ran horrible. Would not idle, had to hold the trottle down to keep it going and got code for multiple random missfire several times. Its a stock rebuild lq9 a 208/212-.554/.558 115 LSA comp cam and Harland Sharp 1.7 non adjustable Rocker Arms and the heads had .010 shaved off.
After the engine finally warmed up I got a ticking noise out of the rocker arms. Come to find out the a few rocker arms were hitting the bolt bosses on the valvecover and theres some aluminum shavings all over the top end of my valvetrain. I already ordered a pushrod length checker and a dial indicator to verify I am installing the rocker arms correctly.
What I am wanting to know is your thoughts on this as well as how do yall suggest I remove the shavings, can I wash the top end down with oil and then change the oil to remove. (it wasnt alot of shavings but enought to make me concerned)
That and will a tune help it, any reason other than incorrect pushrod lenght cause the engine to run rought, and yes I already checked for vacume leaks and the obviouse stuff
Sorry so long but I am really worried about ruining the engine.
What do yall think???

[AFSP1211]

To my knowledge you're 6.0 will run like poo on the 5.3 tune, so yes, a tune will probably help a little. Are you using the stock push rods? if so, that might be part of the problem? did you change valve springs with the new cam?

[tatersalad25]

I have the tune coming I was just too impatient to wait lol. I am using Trick Flow pushrods but they are the stock 7.4 lenght. And yes I did change valve springs I put in a set of the LS6 Yellow springs. Thanks for the input.

[RedHeartbeat]

The injectors may be clogged or stuck if they are from the salvage yard. Injectors dont like being dry after gettind deposits on them.
they stick shut many times.

[farmtruc]

I'm not saying you have the wrong springs or that they won't work, or others haven't done it, but here's what I just ran into with a 99 fbody.
Customer said he's been through 3 starters and they keep breaking so he wanted us to install the starter.
Right away, I knew something was up, especially since he hasn't driven the car.
Found out that a cam and springs were installed.
The kid used an aftermarket cam and ls6 springs. I never got the full specs on the cam, but according to the serial number on the back of the cam (yes we pulled it and looked it up), it was about a 568 lift.
The car ran terrible and would back fire and hardly run when it was brought in. After we inspected, it appeared that the coils were binding.
Anyway, we tore the heads and cam off.
Most of the valves were bent along with pushrods, some lifters damaged; cam was installed correctly by the kid though.

Since everything was kind of screwed it's hard to tell, but when the engine was turned over by hand, it appeared the coils were touching and no room for spring compression.
Does this sound feasible?
Anyway, got new valves and the heads redone, same came and new 918 lunati springs; everything was fine after that.

Just check that and be sure, hopefully everything is ok.


As for the shavings, I've seen some Harland rockers hit some valve covers and clear others, if it's hitting, you'll have to grind the covers down, I know pita.

Do a quick compression test to ensure everything is ok before you go racing.

[tatersalad25]

thanks for the info, I am off tommorrow afternoon and when I go in to verify pushrod length I will check the springs while I am in there, so how much room should I have inbetween the coils when they are fully compressed?

[molitor]

When I replaced the lifters in my 4.8L recently, i ran into a problem with a shop not grinding the valve stem tips when they did the valve job.(this is a whole other story that is really bad in its own right) Anyway, most of the lifters clattered like crazy when i got the heads put back on and the engine fired up. I ended up getting a set of .025'' shorter pushrods to solve my problem. After that, the lifters were nice and quiet. So I would check pushrod length, coil bind, and run it with the valve covers off to see if the noise is maybe just the rockers hitting the valve covers. By the way, if you didn't wash the rockers thoroughly with solvent when you got them, they would most likely have Al shavings on them from machining and assembly.

[Tank]

I've had some valvetrain issues with mine since the cam/spring swap and valve job... Everyonce in a whille i get a certain valvetrain noise that gradually gets louder and louder... then fades out...
stock pushrods

And i've seen guys run LS6 springs with XER lobes (.581 lift).

[tatersalad25]

Well I measured the pushrods and ended up needing 7.350 length Pushrods so as soon as they get here I will install them with my new computer from Nelsons and hopefully wont have any more problems.....fingers crossed....