Stock rockers and 3/8 pushrods?

[T.mollergren]

Can stock rockers on a 68-69 383 handle 3/8 pushrods, thos sitting there today is 5/16, but new head and lifters want 3/8, will it work or do i have to change the rockers too?

And is there any adjustable rockers for Hydraulic Flat Tappet cam and lifters?

 

[lewtot184]

you can use a 3/8" push rod but it needs 5/16" ball tips. you can get 3/8" adjustable push rods with 5/16" tips if desired. there's a variety of adjustable rockers out there to fit your needs.

 

[Yatzee]

Can stock rockers on a 68-69 383 handle 3/8 pushrods, thos sitting there today is 5/16, but new head and lifters want 3/8, will it work or do i have to change the rockers too?

And is there any adjustable rockers for Hydraulic Flat Tappet cam and lifters?

They are not really necessary with hydraulic lifters and neither are 3/8 rods. You'd have to have some pretty stout valve springs and lift to go 3/8, like 1000+ HP. Clearance through the rod ports in the head could also be a concern especially at the extremes of valve opening and closing where the rockers push the rod to and aft.