clatter/clatter

The sound of my motor is driving me nuts. I've got a 2275 SCAT motor with a street racer cam and lube-a-lobe lifters that make a valve train noise that is not the high performance clatter I want to hear. I've got a A1 exhaust system with a nice sound, but the rattling of those valves is all I can hear. They are not out of spec adjustment. I was told that the SCAT motor has steel pushrods and that makes the valves bang around, but I don't really hear other big motors being so noisy. I saw some really cool roller rockers, are they any better? Any ideas for a fix will be appreciated.

What have you set the valve lash at?

With chromoly steel push rods, you should be running the valve clearance at .002" or so (I wouldn't go any looser).

The Raby Type IV engine I had was set at zero lash cold ( chromoly push rods)and would open to 006 when at operation temps per Jake Raby

I just bought a set of Pauter rockers, I'll let you know how they sound.

Dennis,

Some of the performance engine builders use a straight cut cam gear. If you have one you are going to get some noise, screech, squeal or whine. Check your build sheet and let us know.

Karl

thanks for your help guys. Sorry I've been out of town so I didn't get back to you sooner.
SCAT the builder sets the lash at 002" and I had them set tighter last service. It helped a little. Yes the pushrods are chromoly, but the valves rattle when cold also. Karl I don't mind whine, screech, or squeal, it's the rattle like a old worn out VW that is fouling my beautiful speedsters image.
David I don't know what Pauter rockers are, are they roller type. Let me know if they are quiet. Those machined roller rockers really look good and I'm all about looks and sounds.
Any other suggestions will certainly be appreciated.
Thanks again.
Dennis

Are you sure the problem is not the A1 exhaust. TIger told me that it is so quiet all you hear is the "sound of the engine". That would drive me nuts so I opted for more exhaust tone to muffle the engine noises. If I cover my exhaust tips my 1776 is pretty noisy. Of course you have a majorly pumped motor and is no doubt much louder than mine.
Good luck.

Dennis,
Chromoly pushrods are aways noisy. Those things weigh a ton. If you don't need that bullet-proof pushrod set up, try aluminum push rods. They'll make the valve train less noisy than chromoly.

Greg B

Greg; I understand that aluminum pushrods might not be able to take the brunt of a larger motor such as Dennis'. It would be a good idea to verify that before jumping in.