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Yelcamino
01-22-2007, 04:20 PM
I have a freshly built 355 Chevy, it's a basic small block w/ Edelbrock Performer heads, Performer intake, Carb Shop built Q-jet, Comp HE268 cam/lifters/pushrods/roller-tip rockers, HEI, and headers.

The problem is no matter how many times I adjust the valves or how I adjust them, they're noisy as hell! :banghead:

There's no carpet or insulation on the floor so I blame some of the noise on that, but it just seems to me the valvetrain should be a little quieter. Any ideas? Thanks.

6'9"Witha69
01-22-2007, 04:25 PM
How are you adjusting the valves?

LowBuckX
01-23-2007, 12:28 AM
Thats the High energy 268 ? flat hydraulic?

Have you adjusted them hot with the engine running?
Get engine to operating temp
shut engine off
pull 1 valve cover
fire it back up
loosen nut till you here rocker tap
tighten it till it just stops
give it a 1/4 turn more move on to next valve.

its messy so be fast. Works very well

Yelcamino
01-23-2007, 03:19 AM
I've adjusted the valves two different ways, multiple times.

The first way I did it was to get the engine to operating temp, then do one cylinder at a time with one valve on the base of the lobe tightening the nut until feeling resistance to spinning the pushrod then turning the nut about a quarter turn more. It's time consuming but no mess.

The other way I did it was with the engine running at operating temp backing off each nut until I heard the lifter tapping then tightening the nut until the tapping stops.

Either way it sounds fine idling in the garage, but once I drive down the street the valves are just as noisy as they were before. Could it be the roller tip rockers simply make more noise then non-roller tip rockers?

Yelcamino
01-23-2007, 03:23 AM
Thats the High energy 268 ? flat hydraulic?

Have you adjusted them hot with the engine running?

Yes, the High Energy 268 flat tappet hydraulic.
And yes I've adjusted them hot while the engine was running. To reduce the mess I have a steel valve cover with the top cut open.

TPI Monte SS
01-23-2007, 09:37 AM
My experience has been that roller-tip rockers are just annoyingly loud. I've adjusted the valves several times with these rockers (three times when they were on the 305, once with the 355) and they just tick. Mine are Comp Cams aluminum-body roller rockers.

Yelcamino
01-24-2007, 03:24 AM
My experience has been that roller-tip rockers are just annoyingly loud.

Considering how many times I've adjusted the valves, I'm starting to think the same thing. My El Camino has Jesel shaft rockers and they're noisy too, but not quite as noisy as the roller tip rockers on my Blazer. I guess it's something I'll have to live with.

Thanks.

Herb

USAZR1
01-24-2007, 04:25 PM
Comp's HE cams have pretty aggressive ramps and seem to be noisier as a result.

CarlC
01-24-2007, 05:08 PM
Here's what worked well for me.

Using a starter button, turn the engine until the intake valve just closes. Adjust the exhaust valve 1/4-turn past zero lash. Turn the engine over until the exhaust valve just starts to open. Adjust the intake valve 1/4-turn past zero lash. Move to the next cylinder.

My old XE268 was a bit noisy.

Yelcamino
01-24-2007, 06:17 PM
Comp's HE cams have pretty aggressive ramps and seem to be noisier as a result.

Hey Clint,

If that's the case then once the valves are adjusted, there's not much else to do.

I'm sure when I put some sound control and carpet in, a lot of the noises I hear will no longer be audible.

Herb

Yelcamino
01-24-2007, 06:19 PM
Here's what worked well for me.

Using a starter button, turn the engine until the intake valve just closes. Adjust the exhaust valve 1/4-turn past zero lash. Turn the engine over until the exhaust valve just starts to open. Adjust the intake valve 1/4-turn past zero lash. Move to the next cylinder.

My old XE268 was a bit noisy.

CarlC,

The way you described is how I normally adjust my valves except instead of the starter button, I use a breaker bar/socket on the balancer bolt with the spark plugs removed. I have electric fans on my cars, which gives me plenty of room to work.

Herb