409 with Scorpion 1.75 lifters

[Red 409 63 impala]

Just wondering if anyone has had strange metallic sounds with these rocker arms. 409 with a hydraulic camshaft. (not sure of make). When I start it sounds like the rockers are hitting the valve cover. They are the Edelbrock aluminum covers. I removed them and no sign of them being hit. I then removed them and started the engine still heard the noise. (metallic sound)...the engine was rebuilt just before I purchased it, but not run for years, still has the break in oil in it. The valves are adjusted correctly.

 

[MRHP]

Yes, my Scorpions make noise until they get flooded with oil. Acoustical signature would be a good description.

 

[409newby]

My car has the same rockers would make a rattle/clicking noise, original valve covers, put 3/8 spacers on end of problem

 

[scott hall]

Which heads do you have. The small port heads the end rockers will hit front and rear. Doesn’t on large port. There is like a good size difference in valve cover rail height on the heads. I used two gaskets to get then to clear on some 817 heads with stock or offenhouser covers. Both hit. Also a solid roller cam so noise I heard was valve clearance.

 

[MRHP]

Mine has aluminum covers and do not hit. I even asked the same question a few years back. I believe the side motion on the rockers is what makes the noise. Once it has run for a minute or so, and the rocker is flooded with oil, the noise nearly disappears. Mine has been doing it for 16 years. Rockers are still like new.

 

[Ishiftem]

Where is the altered?

 

[W Head]

I have Offy valve covers and had to use double stacked cork gaskets to keep my rockers off the valve covers.

W Head

59 Impala 409-2,4s

 

[MRHP]

The altered is in the trailer Dan.

 

[Ishiftem]

When are we going to the grove?

 

[Ishiftem]

I'm bored!

 

[4speedman]

I have the scorpion rockers and they make quite a noise but i have over 5000 miles on this engine over about 16 years an have not had a problem and i use stock valve covers and they don't hit the covers.My cam card says set the valves at .030 and i did that them tried .028 and it made no differance in the noise.I have gotten used to the sound and kinda like it.

 

[MRHP]

As soon as it’s done Dan. SOON!

 

[Red 409 63 impala]

I pulled the valve covers, and I have the 690 heads. The engine was rebuilt professionally. Is there anything to look for.

 

[Red 409 63 impala]

Another thing I noticed is the rockers are 1.75 ratio. Why would this ratio be selected? I noticed you can buy them with different ratios.

 

[Phil Reed]

That was the factory ratio for 348 and 409 engines.

 

[models916]

1.75 factory

 

[heddrik]

Are we there yet?

When are we going to the grove?

 

[Ishiftem]

If "there" is crazy then yes, we have arrived. In fact I think I was early.

 

[Iowa 409 Guy]

If "there" is crazy then yes, we have arrived. In fact I think I was early.

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