hello, i am building my 300 in my 79 f 250 4wd and it is a 4spd , when finished it will have a 6in skyjacker lift and be turning 36in tires, i have most of my parts for the motor just kinda stuck on which cam to buy. i have the offenhauser dual port intake and a hedman header, and edelbrock 500cfm carb. i will be using the chevy rockers for some more lift. i am just wondering what cam you guys are using for a similar setup,also wondering if you know of any good igniton upgrades the truck is used aminly for off road and some towing. i am trying to keep power in the lower end. thanks joe

 

Crane make a great "middle of the road" cam that will give you plenty of power without killing your gas mileage or requiring modifications for valve clearance issues. It's a split duration [260 intake/ 272 exhaust] profile which really benefits the 300's "stuffy" heads and exhaust. Part # is 503905, it's in their "powermax" line and only runs about $110 from Summit.

Have always been a Comp Cams fan... but their closest offering [a 250/260 split] just doesn't match up as well in the overall lift and duration profile. Melling and Sealed Power have some inexpensive cams which are almost "stock replacement". They're mild enough doing the Chevy rocker thing alone would probably yield more gain and be much easier.

Do Not use the Chevy rockers AND a hotter-than-stock cam, you'll get too much lift and wind up with pushrod binding issues. You'd also have to install new higher rate valve springs and check for valve clearance issues since your total lift would exceed 0.50". The rocker swap is something that's an alternative to installing a new [mild] cam... not an add-on to a new cam.

If you do go with a new cam, best deal on lifters and pushrods is from Autozone... $1.99ea for lifters and $1.49ea for rods, both high quality Melling parts.