I would not be concerned with running a roller cam on a street engine, I do
not think you will have any concerns, though if you are running a 7500 rpm,
425 hp 289, anything I say might not apply.
For engines that us mortals might own, a roller cam will reduce internal
friction (roller rockers are nice too ) and give a coresponding increase in
horsepower.
It is esential that who ever grinds your cam realizes that you intend to run
roller lifters. The cam must be ground differently, because the roller
lifter always contacts the center of the lifter, but the flat tappet cam
will contact the edges of the lifter as it opens & closes the valve. The cam
& lifters must be designed to work as a unit.
Most modern OEM engines run roller lifters, and even under little old lady
use, we see few cam failures.
BTW. There are plenty of standard grind roller lifter cams available, are
you sure you want to spend the money for a custom grind cam?
Happy Motoring
Doug Leithauser
Craig Wright wrote:
> > Hi Scott,
> >
> > Your plans sound good except I would worry about a roller cam on the
> > street. Many knowledgeable people that I have spoken with said that they
> > die quick deaths if they spend much time idling. If you are going to use
> > the same profile as the original 289 hp you won't gain any HP by using
> > roller lifters. You can get a lot of HP out of a solid flat tappet cam
> > and still keep it streetable with a long life. I suggest you do some
> > homework before committing to a roller and make sure that it is what you
> > want. I've got a 289 with flat tappet cam, '69 Ford Windsor heads, and
> > it cranks out 425 hp at 7500 rpm [although it is a little high strung
> > for the street ;) ]
> >
> > Craig Wright
> >
> >
> > Scott Hutchinson wrote:
> >
> >
> >>Right now the 260 is sitting on the floor of my garage, the result of a
> >>bad throwout bearing. It is amazing that such a tiny little part can be
> >>the cause of so much work. Any way while the motor is out I am going to
> >>try some minor work to the motor to improve performance, but more
> >>importantly to increase durability and efficiency.
> >>
> >>The plans are thus.
> >>
> >>1. Screw in rocker studs.
> >>2. New valve seats for unleaded gas.
> >>3. Bronze valve guides.
> >>4. Roller rockers. (Probably CompCams Magnums, maybe promagnums but
> >>most people have said this would be over kill.
> >>5. Custom Ground roller camshaft that is basically a reproduction of
> >>the 289 hp cam. It will have the same firing order as the 260 and
> >>should provide a nice hp boost without killing the low end torque.
> >>CompCams will custom grind it for about $300.
> >>6. Crane drop in roller lifters. (no modification to the block
> >>required.)
> >>7. F4B and Holley 1848.
> >>8. Centerforce Clutch.
> >>9. Roller Timing Chain
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