Nastardly

Hello, my dad has a 1958 Chevrolet pickup that he bought with a 350 from a '77 Cutlass. We're having a hard time finding the correct valve cover and gaskets, his 3A heads have 5 holes, all the valve covers and gaskets we have found have 10 holes, which corresponds to my '64 Jetstar 88's 330. Any advice is appreciated.

Fun71

They use the same gasket. The cylinder heads on the 77-later engines are drilled for only 5 of the 10 holes, but the heads have the same shape with 10 "humps" where the bolts go.

Nastardly

Thank you. Are 5 hole valve covers available?

69CSHC

Out of curiosity what valve covers etc came on the engine when you guys bought the vehicle ?

The valve cover gaskets as well as the valve covers are shared across so many years and engine sizes for Oldsmobile V8 that 10 bolt is the default. So my guess you may be hard pressed to find them, unless your going OEM etc.

Here is an original 1979 Oldsmobile 350 with factory 5 bolt valve covers.



http://www.2040-parts.com/1979-olds-...gine-i1409842/

svnt442

Anything aftermarket will have 10 holes, otherwise it would limit fitment.

Gpc1

I have a set with 5 holes, and only 1 hour away from you . I’m located in Martinez.
pm if interested. Thanks

Greg Rogers

Aren't 3A heads from a 307? Maybe i'm wrong but I thought heads for a 350 would be 5 6 7 7a 8 ? Then lower #s over again for 80's 307's?

joe_padavano

Sorry, but you are incorrect. This is one case where the data in the Olds FAQ is actually correct. 77-80 350 motors used lightweight castings with windowed main webs and 3A heads. 403 motors used 4A heads. 307s used 5A, 6A, and 7A heads, depending on year and application.

Nastardly

The engine was in the truck when purchased, it came with 10 hole valve covers. I also noticed this hole in the head, are these incorrect heads for this block? The 330 in my J88 doesn't have this. I really appreciate your help. I have been telling my dad all about you guys, especially Joe Padavano who knows everything about oldsmobiles for the last few days.

joe_padavano

People always worry about this, despite the fact that the engine has run fine for decades. The "hole" is just a pocket to reduce weight. The 1977-up Olds motors used block and head castings that had excess metal left out to reduce weight for better mileage. They also have windowed main webs.

Nastardly

I just wanted to make sure it wasn't engine parts cannibalized together that shouldn't be. Thank you.

olds 307 and 403

Just use RTV to fill the extra holes for now and done.