DETROIT_AREA_00_SS

iTrader: (7)

Rod knock? Stuck/broken lifter? Broken double valve spring?


Ls2 70k miles
229-236(.624/.617)-112
.650 double valve springs
American Racing 1 7/8 catless
Vararam

Mustang dyno tuned at 449rwhp about a month ago. Noise started during normal driving, not hard driving.

65Chevelle

iTrader: (3)

loose spark plug? Find using automotive stethoscope.

DETROIT_AREA_00_SS

iTrader: (7)

I hope it's something that simple...

Crf450r420

iTrader: (1)

If it is internal it is most likely a lifter. You can put thicker oil in and if the lifter pumps up you can keep running the oil and or choose to change the lifter. I think that most of the lifter issues where the displacement on demand style. Like the first post check or the simple things. You can use a two by four to heat or a long socket extension. Valve train noise is more rapid than crank and rod knocks.

DETROIT_AREA_00_SS

iTrader: (7)

My lifters have always been noisy in this car, beyond the typical LS valve train noise. I have had 7 or 8 LS motors and this one has been far more noticeable. A well known LS specific shop said it was still normal though.

I will start tearing it in a week or so after checking some simple things.

DETROIT_AREA_00_SS

iTrader: (7)

I've never heard rod knock first hand though so I don't know what it sounds like.

handyandy496

iTrader: (9)

how is your oil pressure?

handyandy496

iTrader: (9)

sounds like valve train. performance still ok?

handyandy496

iTrader: (9)

all of that noise could be taken out with longer pushrods possibly. recheck wear pattern on valve tops and roll your pushrods on a flat surface you could have bent one or more.

DETROIT_AREA_00_SS

iTrader: (7)

When I did the cam they put in hardened pushrods, comp I think. I didn't miss a shift or over Rev, that's why I don't think it's the pushrods.

Oil pressure hasn't changed. 38psi at idle. Oil temp is normal too.

I literally just finished an oil change, put in 10w-30 Dino.... Slightly quieter but still very noticeable.

DETROIT_AREA_00_SS

iTrader: (7)

Performance feels normal but obviously I haven't gone WOT or even over 2500rpm.

LS1MCSS

iTrader: (18)

To me, it just sounds like the pushrods are too short. Get someone to check for the correct length and then check yours to see what they are.

Anthony Phillips

first id pull valvecover and check for broken outer spring in the valve ,happens kinda regular...don't beat on it though(engine)def in valvetrain though possibly short pushrods as well!!

Anthony Phillips

while valvecover is off check for rocker play

DETROIT_AREA_00_SS

iTrader: (7)

I don't think its pushrods because it has run very strong for 15k miles since cam/springs...etc were done. I am out of town for 2 days, I'll yank the covers when I get back.

DETROIT_AREA_00_SS

iTrader: (7)

Back in town....

So I started it today and the same noise was obvious... Drove it 15 miles to friend's house and now the noise is few and far between.

I am going to pull vavle covers tonight.

newschool72

iTrader: (12)

Sounds like a header leak, coming from the bottom of the header flange . I would check that first.

DETROIT_AREA_00_SS

iTrader: (7)

Update! It was a lifter. Cam is ruined too.

Jimbo1367

ouch. Might want to cut the oil filter apart and check for metal debris.

DETROIT_AREA_00_SS

iTrader: (7)

I'm going turbo so I am yanking this LS2 and throwing in a forged shortblock and turbo friendly cam. I don't want to take the risk leaving this shortblock in with all this metal floating around. The cylinder walls have some vertical lines as well.

Oh well....