simple question
will hydraulic roller lifters clear the bores on a non-roller motor?

thanks

-6kyles7

 

If you buy a "retrofit" (reduced base circle) cam, yes, and in my experience they work fine.

http://www.summitracing.com/search/M...d=retrofit+cam

 

now i notice the lifters dont come with the link like some others do
is this a big deal?

 

The comp can kits come with a stock Ford style "spider and bones" to maintain lifter alignment, The Howard Cams kits show linked lifters in their photo, but when I ordered my first Comp Cams kit the photo showed linked lifters and I got spider and bones, so no guarantee.

The linked lifters look cooler, and some claim they work better, but I am satisfied with the spider and bones on two of my engines, and they worked for Ford ok.

 

Yes. And that's the problem. Roller lifters are taller than flat tappet, because of the roller wheel on the bottom. For that, Ford made the block lifter bores taller. If you drop roller lifters into a non-roller block with a non-retrofit cam, they will stick up too high and expose the oil feed holes. Then bad things happen.

You have two choices, both (I think) have their place.

Use a retrofit cam, with a smaller base circle. That drops the lifters down in the bore far enough to operate correctly. You can use Ford parts for this: lifters, dog bones, spider. You'll need to drill and tap two small holes in the valley to retain the spider. And you'll need to grind for clearance in a few areas to make room for the dog bones. Pretty simple operations that most anybody can do. No need for a machine shop bill there.

The advantage is that it's relativly inexpensive, and extremly durable. Ford roller lifters last about forever. The down side, not the strongest camshaft, because it's thinner. If you're racing and using high spring pressures, the cam can twist and pogo, causing erratic valve timing.

The other option is to use link bar lifters. The lifters cost about 3x what Ford parts cost. They're aftermarket, and may not be as durable. But you can use any Windsor cam. There are no holes to drill or spots to grind, it really is a simple drop in operation. If you're racing and using big springs, this is probably your best option.

If you upgrade to a roller cam, be sure and change your distributer gear. Otherwise, you'll be rebuilding the engine.

Either of the above choices will require custom length push rods.

If you havn't already done so, plan on getting rid of the stock non-adjustable valve train. Once you start making changes like this, the stock parts won't fit any more.