HO means high output. this explains everything.
COOL CATS :: Tech Center: Advanced: Standard-to-High Output 5.0 Conversion
COOL CATS :: Tech Center: Advanced: Standard-to-High Output 5.0 Conversion
All the 85+ 5.0L engines are "roller-ready", meaning they have longer lifter bores than previous 302/5.0L engines and can use roller lifters and matching hardened cam. Even the low-po 5.0L found in 1985+ Lincoln town cars and Ford Crown Victorias and pickups are "roller-ready". Only the HO engines found in the 1985+ Mustangs, Lincoln Mark VII LSCs and later Cougars/T-Birds actually came from the factory with roller lifters and roller cam. The others were fitted with the same block but anemic flat tappet cams/lifter combos. Relatively easy and cheap to convert, though.
Daniel
Daniel
You forgot to mention the threaded holes for the roller spider in the post 85 blocks. This is to stop the Roller lifters from turning inside the bore. If you do the conversion do not forget this. It is very important. I have seen 4 or 5 guys forget the spider and make a real mess out of things.
True enough! There is more to "just replace cam and lifters and you're done" to this conversion. You will need the spider, 2 mounting bolts and the dogbones. You will also need new correct length pushrods and might as well get new rockers while you are at it. You may need shims if you have pedestal mount rockers. You also need either a new steel gear (with correct shaft diameter) for the distributor or replace the dizzy with a 1985 HO 5spd unit. All of these (depending on the type of rockers) will be inexpensive, widely available and relatively easy to install.
Wrong info here.