Not mine they run pretty quiet, you running guide plates and have the proper rocker arm geometry ? you might need to check and make sure the geometry is correct. i take it is a hyd cam ?


Cole
imp:

 

Another thing what heads and what valve springs any work been done to the heads ?


Cole
imp:

 

Hi Cole,
Im using raised guide plates on a hyd flat tappet cam,the heads are new procomps, im using +100 pushrods and +100 valves,I didnt check geometry
they are quiet when the oil is cool then start getting a bit "tappity" when the
motor warms up, They are cheap roller rockers though! I will get rid of them if
thats the reason!
Thanks Dave

 

I have run roller tip rocker arms and my current setup is Comp full roller rockers and I find them to be a little noisey and like you, I questioned 2 different engine builders that I know and they said that they will be a little noisey compared to the stock stuff. I have checked my valve lash a couple of times and everything is fine. My engine is a 406 chevy with Dart Pro-1 aluminum heads and I verified my geometry and pushrod length and all was good. The engine has been together for just over 3 years and runs really good now that I put some miles on it. If everything checks out on your engine, I wouldn't be concerned, jmo..

 

Thanks for that,this is what I mean some say they are quiet and some say
they are a little noisey,I checked valve lash as well,they seem noisy when
the motor is hot!

 

im running comp high energy aluminum roller rockers 185$ a set from summit and they are quiet as can be.

 

347 stroker,Alu roller rockers, guide plates, hydraulic mild flat cam, edelbrock performer RPM heads. Very quiet running and when the oil temp is hot a slight mechanical noise can be heard which would be the lifters bleeding off a little quicker. A little over a thousand miles with no lash adjustment needed.
Al.

 

I have been a drag racer for a long time. You need to be careful using the procomp stuff. It is cheap junk and you would be better off saving your money and getting a quality product. I would rather use old wore out cranes than new procomp.

 

Dave - this is generally how I do mine and it assumes you have 3/8"-24 threads/inch studs:

A 3/8-24 thread which is actually the "pitch" and is also 24 threads per inch.

1.000" divided by 24 is .0416 so this is your preload at 1 turn. Divided .0416 by 4 and you get .0104 for a quarter turn of that polylock/nut. Therefore .0104 X 3 is .0312" for 3/4 of a turn. This then figures on a 24 threads per inch 'pitch' is .0314 as your lifter preload. This will put you within normal lifter preload for most cases and is where I leave mine - and the rockers have only a very minor 'tick'.

A 7/16-20 thread/pitch is figured the same way, but that same 3/4 turn is a bit more(~.006)

1.000 divided by 20 = .0500 for one full turn divided by 4 is then .0125. Three quarters of a turn would then be .0125 x 3 = .0375".

I also use a dial indicator to give me cam opening and closing events and the Comp Cams instructions, which while about the same as my Crane's, are easier to understand while standing with your head under the hood with lousy lighting trying to figure out what some tech writer thought was coherent.

What I found was the hardest was to get all of the slop out of the push rod as quite often they would stick in the lifter and give a false reading and it's start over time.

Another test you should consider is whether that rocker tip roller is centered on the valve tip. You need to pull one or two each, intake and exhaust, clean that valve tip then color it with a dry erase marker. Reassemble, readjust the preload, then roll the engine over 3-4 revolutions. Remove those test rockers and check the contact area. It should be on or very nearly centered - mine are off by about .010. This will determine whether the push rods are the correct length (alternate to using soft springs and a special push rod checker)

Oh and the spark plugs - they need to be out for ease of turning that engine via the crank bolt.

Confused yet??

Dave W

 

Try a diffeent oil. There is a big difference in the vet viscosity of different oils as they warm up
in the running engine. This has a big effect on the hyd lifter bleed down rate at idle at different running temps.
and the valve train noise at idle.

Comp extreme energy hyd cams and other fast action hyd cams are noisyer than other more tame ramp hyd cam lobe designs. They are (a bit) more noisey at idle. especually when other factors stack up.
Mine is as noisey or noiseyer than some solid lfiter cams at idle.
(not near as bad with a better thicker oil)

Some roller rockers are just plane noisey at idle. I found the Scorpions are quiet.


GM hyd lifter are high quality. The ones with the steel foot are the best.

Push rod tip radius to rocker cup radius mismatch will create noise.

Start with a different oil. 15w-40 rotella works for me. A good bit quieter than 10w 30 oil in my 406
with ex hyd cam, standard hyd lifters and stock type HD ball stud rockers.

Remember the fast ramp design of the XE, Voodoo cams etc is going to be a bit more noisey at idle them
a stock cam hyd ramp. There is no free lunch.

Change the oil and reset the hyd valve train while hot and running. Give it the preload it wants.
If it want 1 full turn give it that.
A crappy roller rocker just amplifies any fast action hyd valve train running noise.
As stated correct valve train geometry is critical ( push rod length)
Basic lifter to lifter bore diameter clearance is a factor.
engine bearing clearance is a factor (hot idle pressure at idle)

SBC distributor body dimention size is a factor. Forms part of the right hand lifter oil gallery
Can create excessive oil pressure leakage resulting in low(er) oil pressure at idle in the right hand lifter oil gallery.

Is it noisey at 2000 RPM?

It is hardly noisy at 2000rpm and does not sound noisy when the motor is cold.
Thanks for the information just working down it.
I only changed to new heads,left the cam and lifters as they were!
The stamped rockers were very quiet.I used full roller rockers on new heads
and guide plates.
I did however put the distributor back in differently,I had number one
on the cap originally close to number 7 cylinder,When I reinstalled it
I had number 1 close to number 2 cylinder if that makes any difference
to the oiling ??
Thanks again

 

Thanks everyone for your ideas,and yes irelands child you did confuse me!
But I do apreciate you trying to help me!
thanks again

 

Where the distributor is pointed makes no difference in the oiling of the engine or how it runs. As long as the wires are hooked up correctly and it's timed correctly, it should run good.

Keith