283 year valve covers

I picked up a 1958 283 for a project Im doing . It has side motor mounts,I believe 58 was the first year for that. Has the staggered bolt pattern on the valve covers. Ive got differant info on that some say 58 and up they were straight across others say 58 still had stagered any one know for sure ? Thanks

 

are you sure someone didnt put a 265 in it. by late 56 I think they were all even across ?

 

55-58 were staggered. 59 up straight across.

 

I'm going with 58 as being the last year for staggered. I sold probaly 20 pair of those on ebay back in my ebay days... always listed them as 55-58 and never had a complaint.

 

We used to hear March 1959 was the cutoff date ...

 

Some real early 59's had staggered bolt heads. All 58's for sure.

 

Nope according to casting numbers and motor number below pass head comes up 58 283. Thanks

 

Thanks to all for the fast responses. Im now sure of what I have and can move ahead,found a set of OLD finned valve covers for stagered bolts will be snatching them up. Has a 2 bbl manifold ,I have an old cast 4 bbl manifold but looking for one with the oil fill tube,gonna try to look old school. I havent seen any new manifolds with the fill tube ,probably just find an old one and if I have to use a square bore adapter its going in my 64 6cycl S.S. Nova ....

 

I recently sold a pair of '59 power pack heads with a January 14, '59 casting date and they still had staggered valve cover boltholes then. As far as the intake goes, look for an old Edelbrock C4B, C3B, or C3BX; they all had the hole for the oil fill tube.

 

Mid '59 for sure! DD

 

Another vote for mid-59 as the change-over for staggered to straight across valves cover hold down bolts. Butch/56sedandelivery.

 

I need more info on determining my year model engine, from what I can tell I have staggered bolts for the valve cover and with this install I have hardly any clearance for casting I D. Are there more ways to confirm year of MFR and cubic inch?

 

If you remove a valve cover, the casting date code and casting number on the cylinder head would be of some help, but 60 plus years after the fact, any block could have ended up with any set of heads on it.

 

You can look at the numbers stamped on the block(flat spot/pad) pass. Side below head, that will usually give you an idea, but need the ones buried against your firewall...

 

I have a nice 283 a bud gave me, freshened it up with Hastings cast rings, Fed Mogul rod & main brgs.
Son #1 gave me a new Edelbrock cam & hyd. lifters, and pal "Stormin' Norman" laid a pair of 265 heads on me!
I have some single point 283 heads, but guides are worn and I'd have to fire up my Sioux valve machine to do a valve job.
Now, "Stormin" just did a nice valve job on these 265 heads, and gave me a perfect pair of staggered Corvette valve covers with the heads.
I have a small port intake (3 X 2) that would fit nicely... I want to use the 265 heads. What do you think?
High compression, small valves, speed up the incoming charge... Or do the single point?
-distressed in Atwater

 

Mike
They say don't choose your camshaft from the bottom of the page, I say "road apples".

 

If your pal gave you fresh ‘56 Power Pack heads consider that they have 55cc chambers and will bump the compression up. Having the valve job would be a plus for me and I’d use them, what would the compression be, maybe 9-1? If the cam your son gave you is the 2102 I’d say you’re good to go with a nice combination.
The 283 heads will have the same valves but slightly bigger ports and I think a few more CC’s. The disadvantage with them is they need guides and a valve job.

 

I go for 59 In 1970 or so I bought a wrecked 1959 wagon for the engine it had staggered valve cover bolts.

 

The block casting number will give you a "kind of an idea" as to the year but isn't an absolute. I've found that aiming my phone or my small digital camera down behind the left head (US drivers side) and takeing some shots usually will get a usable image after a few tries.
The Suffix number as Hollywood- East took the effort to point out is probably your best bet for finding out what the block left the factory in and when. = Small block chevy suffix decode will get you to info on that.
Popping a valve cover off and getting the cylinder head casting number and searching that will give you the info on the head.

A good pair of power pack heads, a mid 80's Z28 cam and a decent intake will help it run pretty decent.