chevy head question

What are the difference to staggered valve cover bolt holes and the non staggered bolt holes other than the obvious staggered and non staggered valve cover bolt holes?

Are the non staggered holes earlier heads?

 

Staggered holes (top two holes are closer together than bottom two holes) were used from 1955 to mid 1959 production, then they were all "straight" holes.

so only early heads have staggered holes

 

There are many differences in the staggered hole versions by themselves without comparing them the the "straight" holes.

 

I got a 283 long block in a trade and never noticed the holes for the valve covers until yesterday when i bought some staggered hole cal custom finned valve covers. Now the search is on for staggered heads

 

Look for a set of power packs with the little triangle on top of the rectangle on the end. That is the minimum you want for a good little street engine.
They came on four barrel equipped cars.

 

Hey, I have some of those.....


although the last pair I sold went for about five bills

 

I have heard people saying power pack. Never knew the distinction. I will keep my eyes open more, and my wallet open. Thanks guys

 

Are 333882 heads worth getting for $50? I am building a 283 and found them on cl

 

they're not what I would use on a 283

 

What is the difference between the powerpack and the double hump heads?

 

They're both the small chamber design, but the powerpack has smaller ports and valves than the double hump. Powerpack is the high perf head for a 283, double hump is for a 327.

although you can put any head on any engine, mostly

 

Don't put heads with 2.02" valves on a 283, the bore is not large enough...

 

That might be true, fortunately there are very few original Chevy heads that came with 2.02 valves

 

Thanks Jim. I will hang onto my 50 bucks for some 997's if i can ever find a set