sickREDsierra

iTrader: (17)

damnit! is there anything i can do to quiet this down?

ever since i changed the cam, it has sounded like a dadgum sewing machine..... i didnt figure that should happen with this small cam .522/.529 212/218 on 114 LSA... it has LS6 springs with manley hardened 7.4" pushrods...

it gets louder at certain rpm's while cruising, sometimes you cant even hear it... then sometimes its loud after i spray it at the track, but then it quiets back to normal sewing machine sounds...

i have pulled the valve covers and checked the torque on the rockers about 5 times, checked that the pushrods were in there correct pivot points with the rocker arms.... its making me paranoid.

WTF???

black4.8

iTrader: (1)

that cam and springs shouldn't make much more noise than stock cam, i wouldn't think. if the rockers are torqued right than you should be fine.

Gator

Did you set the pre-load between .075" to .125"? remember the base circle on after market cams are .050" smaller then stock..you may need longer PRs..
with the lifter on the base circle of the cam with zero lash you want between 3/4 to 1 1/4 turn to seat the rocker arm. then you torque the bolt

WFOsierra

iTrader: (1)

explain this preload stuff a lil bit more Gator, when i reinstalled my rockers i ran them down to snug with a 1.4 drive ratchet and then i tourqed them down to 22ft lbs...thats basically the way ur sayin isnt it? i also used a set of chromolly 7.400 pushrods...u sayin those are to small?

TouchOfEvil04

iTrader: (13)

mine is loud as hell and even on my stock motor rcsb i can hear the damn things like a quite sowing machine lol.
not as loud as the 6.0 but i can still hear it.

Gator

Preload is the amout you compress the lifter plunger while on the base circle of the cam....and the way i set it is to pick a valve that is easy to reach...let say number 1 exhaust valve....position the the cam so that # 1 exh valve lifter is on the basecircle....while spinning the push rod between two fingers start tightening the rocker arm bolt very very slowly... the instant it's stops spinning your then at zero lash (no preload) now from that point on while tightening the rocker arm bolt this is where your getting the preload..you want between 3/4 to about a turn and a half for the rocker arm bolt to seat...(or you can use a dial indicator and measure for .075" to .125") Now once you have that set and between the range above then you can torque the bolt to spec...if you don't have enough preload then it's going to be noise as hell, too much and it will run bad and could damage a lifter, push rod or even the cam...
If you don't have enough preload then you will need longer push rods and shorter if you have too much.

Actually it's very simple to do...but kind of hard to explian in words...hope this has helped a little

budhayes3

iTrader: (19)

The rockers on the GENIII motors aren't set this way, they're just torqued to 22 lb/ft. If the preload is off, you have to get a different size pushrod. A pushrod length checker is only like $12.

FWIW, my valvetrain is noisy as hell too, and I've been living with it so far. A 7.425 pushrod may help, but I'd check first. I know it sounds wierd, but valvetrain noise after cam swaps seems to be accepted as a "characteristic" of the engine.

jephs422

iTrader: (3)

yep, mine's loud too with the GT2-3. mostly only at first start up when the oil still needs to get there. but after it's warmed up, it quiets down a bit, but it is still way louder than stock. I've been told too that different push rods would help, but it doesn't bother me enough to worry about.

WFOsierra

iTrader: (1)

i am going to be tairing into mine ina few days to change the springs so ill check all this out....i am going to buy a pushrod length checker and see if i could go any longer, maybe help my noise alot.

Gator

Thats my point your not setting anything your checking to see if you need shorter or longer push rods....and yes a push rod checker is another way and a very good way.....