I have a 1960 Pontiac 389 that I want to put 2x4 intake on. Offy list a few but I have been reading stuff and 60 is a strange bird. Some stuff is telling me it has to be 55 to 60 only. Then if you look at the Offy stuff on their description they are saying 55 to 64. So when it comes to Offy stuff is it the same from 55 or 64 or is it 55 or 60 and then 61 to 64? Offy 5604 is calling from 55 to 64 as is 5162. Only one calling for 55 to 60 is 5029 Good luck finding that one. So what is right? I just don't want to drop $400.00 + on an intake and find out it's not a bolt on.
In general as I recall. Most will only work 55-60 and then 60-64. Some aluminum aftermarket intakes would work for all years. The Offy stuff will work all years. You can find them for less than $400.
Does anyone know what the difference is from 60 to 61? If factory doesn't fit how would Offy? Someone has to know.
As I recall the water ports are different. The aftermarket intakes were made with ports to go either way. As I recall......
WvenField is right, it's the water passages that vary widely. Aftermarket manifolds typically have round holes so you can put a freeze plug in the unused holes. The width and gasket surface angles are all the same '55 - 64+. The ports may need massaging but you should port- match whenever changing manifolds. Sent from my iPhone using H.A.M.B.
My understanding is the exhaust crossover ports are different from 55-60 and 61-64. I can't verify this as I never mess with the "late model" 61-64 heads/intakes although my 370 Pontiac has 65-up heads on it to take advantage of the larger valves, ports, screw-in rocker studs and pushrod guide plates but that's a whole different kettle of sheep.
You can swap heads and intakes from all years. for example you can install 400 heads and a 400 intake on a 55 -287 and anyV8 engine Pontiac made except the 301. But to just change the intake only with factory parts its 55 thru 60 . 60 thru 64 and 65 and later. I once installed 400 heads and the matching Qjet intake on a 64 -389. The 55 thru 59 have reverse cooling. and the 55 oiled the rocker arms thru the stud's rather than the pushrod's
I hesitate to nit-pick Old Wolf but Pontiac V/8s oiled through the hollow rocker studs AND the pushrods from 55 to 64. I blocked off the oil galley passage from my '57 block and used 65-up heads. Made no other changes and it now oils the rockers through the pushrods. Seems to make plenty of oil at the rockers.
in 1955 they did not oil thru the pushrods. You can install later hyd lifters and pushrods and convert them but the factory stock 287 don't oil thru the pushrods. I own a 55 GMC with the factory 287 Pontiac engine .
The same way rocker arms on things like a Y block ford did. The rocker fills with oil and there is a weep hole that allows the upper push rod to get oil. It apparently wasn't ideal because by 1956 they had Hyd lifters and pushrod oiling. for all I know some late 287.s might have the dual oiling or it might have been performed under warranty. I know my 55 GMC doesn't oil thru the pushrods. Its a solid lifter engine with a 318 trans. I would like to find a 59 -389 to install in it. A 60 would also fit but I kinda want a 59 engine because it retains the reverse cooling and has those vent holes drilled into the intake valve guides thru the head. The vent holes where to prevent excessive vacuum from drawing oil into the combustion chamber thru the valve guides. the 58 -270 engine also had the vent holes.
Actually, not correct. The rocker balls oil through the hollow studs, and the push rod cup oils through the hollow push rod. Rocky is correct. All nitpicking aside for a moment.
I have also run into interference issues with the rocker arms when using '66 valve covers on the '67 & up heads. The rocker arms punched tiny dents into the older valve covers.
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