59 Heads

[John Farwell]

Would a car built the first week of June, 58 have 550 or 465 heads? 550 was early and 465 is late. 550 have staggered holes. 465 are straight for the valve covers. When is the cut off date? Anyone know?

Happy Holidays and thank you in advance.

Cheers..John

[Jerry C.]

Re: 59 Heads

Are you shure you don't mean June of 59 as no 59's were built in June of 58. The change from 550 to 465 was between May 5th and May 19, 1959.

[John Farwell]

Re: 59 Heads

Thanks Jerry. Yes you are correct...i meant to say June of 59 not 58. So it looks like I need a 465 head.

[Jack H.]

Per the JG Book....

"The earlier (staggered) type heads will appear n cars assembled as late as June or July of 1959...."

This means it was a running change without a clean cutoff date and the factories (both Saginaw/Flint engine and St. Louis final assy) using up what inventory was on hand with the change over being randomly interspersed on final production, out-the-door, cars. So, the choice of which to use is your personal restoration call.

I can tell you, finding a set of '770 heads is going to be easier than finding a set of '550 heads. Why? There were more '770 heads made (longer production run) and Corvette engines switched rather abruptly to the '692 casting in 1960. This makes the effective run of '550 heads relatively small/scarce....