if i wanted to put a roller cam in a midly modded 289 would i need to change the block? what other steps would need to be taken?

 

It depends.. Solid and hydraulic are two different animals with differeing requirements. A factory hydraulic roller cam isnt exactly a bolt in deal, but it can work with the existing block. A solid is a no brainer but is more of a full race type cam, and will require a fully adjustable valvetrain. The valvetrain is a good idea with the hydraulic as well, and any roller will need shorter pushrods because the lifters are so much taller than flat lifters.

 

I am in process of building a 1970 351 with a roller setup, I bought a complete kit that had cam, lifters, pushrods, and a chain kit. It did not include rockers, which I purchased seperatly.

The kit was an "oem style" which meant that I had to install a factory style "spider"in the center of the valley to maintain correct lifter alignment. This was a little tricky as it required me to drill and tap two1/4" holes tohold the spider down. It kind of freaked me outbecause thes holes were right above the cam bearings, so ICAREFULLY drilled these holes to .40 depth, and used a bottomoing tap to finish the threads to the bottom of the holes.

The rest of the assembly seems to be a straight forward affair, which I cant finish untill I get my rotating assembly.... oh well...

Depending on how aggressive you will be going with your cam, (lift) you may need to replace your valve springs & retainers, rocker arms (recomended anyway) and if rockers changed to roller rockers, probably your valve covers.

You might want to consider that your stock 5/16"press in rocker studs may not be acceptable for your new cam selection either. You will probably want to go with 3/8" or 7/16" screw in studs.

 

everyone seems to forget that they sell roller lifter retrofit kits where lifters are connected in pairs of two. this lets you use them in ealry blocks with NO machining. of course, any time your going with a bigger cam an adjustable valvetrain is highly recommended to ensure proper lifter plunge / valve lash.