Colin,
Your probably not going to like my response but here goes. Cam "lope"
is pretty much a hold-over from our carburated days and is caused by
fuel and air reversion in the intake manifold. The fuel/air charge
actually
becomes unbalanced (sometimes rich, sometimes lean) and is a direct
result of overlap of the valves, both being open. Todays engines
generally
have a power band width of 4,000 RPM. We use overlap to push the
power band up the RPM scale to achieve more power. A given here would
be that the intake, exhaust, and fuel delivery are capable of
delivering. In
the Magnum engines, you really need to do a lot of work to increase the
top end breathing (port work, intake work, or supercharging). The best
approach to cam selection is calculations including weight of the
vehicle,
gearing, breathing capabilities of the intake, exhaust flow, and use.
Another factor we need to take into account is engine controller. The
givens surrounding the 318, and 360, we really don't want to take them
much above 5,500, (stock, lifter problems), the intake (tuned for lower
RPM's). Picking a cam with a power band above this would be a waste.
In regards to the computer, at an idle (operating temperature), the
computer
IS looking at the O2 sensor, and really goes nuts trying to adjust to
the
reversion problems caused by high overlap. You will never get a fuel
injected engine (that looks at the O2 sensor at idle), to sound as sweet
as a carburated engine with the same cam (they tend to sound raspy,
and in desperate need of a tune-up). In regards to the Crane cam
PN 704111, the powerband starts at approx. 1,200 and runs up to
about 4,800, top end breathing in the intake manifold, intake and
exhaust ports tends to be the limiting factor. It works very well
as a daily driver in the 318 non-supercharged. If you have a 360, or
your goal is 1/4 mile and your willing to shift around 5,000, I would
probably step up to the Crane PN 704121, powerband 1,400 - 5100.
Now to answer your question, both cams do have a nice smooth idle.
I am probably going to catch a lot of flack from this post, just my
opinion.
Frank
> -----Original Message-----
> From: Vincent Heckathorn [SMTP:victorylane@iwaynet.net]
> Sent: Sunday, August 02, 1998 9:23 PM
> To: dakota-truck@buffnet.net
> Subject: Re: DML: RE: Cams, I made a mistake;
>
> Does the 704111 cam lope any at idle? and what is the rpm range of it
> ?
> Colin
>
> Holloway,Frank T wrote:
>
> > Hay Patrick and Eric,
> >
> > I made a mistake with the Crane cam specs I gave you. The cam spec
> > sheet that I pulled out (way too many pieces of paper around here),
> > cam PN 694111 was actually for a "NON MAGNUM" 360 I built up many
> > years ago. The one that I have in my 360 MAGNUM is PN 704111,
> > (found the correct spec. sheet and did verify in in the Crane
> catalog).
> > Specs are:
> >
> > Advertised Duration (250/260), @ .050 (194/204), lift .434/.458
> > lobe sep. 112 deg.
> >
> > Crane also has another cam that offers additional breathing on the
> top
> > end.
> > PN 704121 Specs are:
> >
> > Advertised Duration (260/264), @ .050 (204/208), lift .458/.467
> > lobe sep. 114 deg.
> > Looks like it might be better in non-automatic trucks.
> >
> > Again PN 694111 WILL NOT fit in a MAGNUM engine. Sorry for the
> mistake.
> >
> > Different subject,
> > The studs for the Crower rocker arms, are they a direct fit or do
> you
> > need to
> > drill and re-tap. If they are a direct fit, Does Crower offer a
> larger
> > rocker stud?????
> >
> > Frank
> >
> > > -----Original Message-----
> > > From: Holloway,Frank T [SMTP:Frank.T.Holloway@kp.org]
> > > Sent: Sunday, August 02, 1998 1:16 PM
> > > To: 'dakota-truck@buffnet.net'
> > > Subject: RE: DML: RE: wanted 94-95 ram, & cams
> > >
> > > Patrick & Eric,
> > >
> > > Lots of thoughts here, one of the reasons that I initially said a
> Ram
> > > was because of the shape the interior is in. Factory AM/FM/CD,
> > > electric seats, SLT, etc, etc etc. I'd hate to throw it into the
> > > dumpster.
> > > Rims, tires, rotors, rearend (sure grip), everything (but the
> body) is
> > > in good
> > > shape. I also thought that it might be easier to come by a 94 or
> newer
> > > Ram
> > > and transplant everything, Even a theft recovery would be good. It
> > > will
> > > take me
> > > a couple of months to tear down the engine and build it the way I
> want
> > > it.
> > > Earlier you were talking about your cam selection and the specs on
> the
> > > Comp.
> > > cam you run.
> > > I run a cam with 264/274 adv dur (210/220) that gets .512 lift
> with
> > > 1.6
> > > rockers, and it's on a 112 deg lobe sep angle... Powerband seems
> to
> > > peak
> > > right
> > > at the stock 5200 rpm rev limiter, but a few more Rs wouldn't hurt
> > > (5500
> > > shifts would be ideal).
> > > The cam I generally use is a Crane product PN 694111, specs.
> > > advertised duration (260/250), @ .050 lift (204/194), lift
> .429/.407
> > > with a lobe sep.
> > > angle of 112 deg. Powerband 1,200 through 4,800. I really like
> this
> > > grind, idle is
> > > excellent, and it works well with both the factory, Mopar
> Performance,
> > > and aftermarket
> > > controllers, also works well in both supercharged and
> non-supercharged
> > > environments.
> > > Also another thought, flow though the Magnum heads tends to fall
> off
> > > in
> > > the lift range
> > > greater than .400. I realize that there are gains to be had with
> > > greater
> > > lifts, (greater
> > > ramp angles etc., but I have had nothing but problems with the
> rocker
> > > hold-down bolts
> > > and sleds (broke two). On this 5.9 I just pulled out, I'm gonna
> try to
> > > find a stud/rocker-arm/
> > > guide plate conbination that will work with these heads. On the
> > > subject
> > > of 98's and the
> > > increase in HP and torque, exhaust has been changed and I am sure
> that
> > > has contributed
> > > to the increase. But look at the torque curve, has been raised by
> > > about
> > > 400 RPM. This
> > > is generally the result of a cam change. I am not absolutely sure,
> but
> > > I
> > > would almost bet
> > > on it. Two additional thoughts, supercharging generally raises
> both
> > > the
> > > torque and horsepower
> > > peeks, on the above cam, 6 lbs boost, torque peak was up by 500
> RPM.
> > > On
> > > your truck,
> > > if the controller is factory 94 or 95, It has a removable PROM and
> > > Superchips can remove
> > > the rev and top speed limitors for you. DON'T take it too
> high......
> > >
> > > Frank
> > >
> > > > -----Original Message-----
> > > > From: Rekker21@aol.com [SMTP:Rekker21@aol.com]
> > > > Sent: Sunday, August 02, 1998 9:48 AM
> > > > To: dakota-truck@buffnet.net
> > > > Subject: Re: DML: RE: wanted 94-95 ram
> > > >
> > > > In a message dated 98-08-02 12:27:38 EDT, you write:
> > > >
> > > > << Frank,
> > > > > I'm probably with about 200 other people wondering why you
> > > didnt
> > > > > drop that puppy right into your Dak! I wouldn't even think
> of
> > > > selling
> > > > > it, I'd be trying to find a way to pop that in and be special
> > > > ordering
> > > > > myself a set of 5.9L R/T decals from the dealer!
> > > > > How may others are drooling right now?!
> > > > > Patrick
> > > > >>
> > > > Yeah Frank, If I can do it so can you!! You sound much more
> > > > mechanically
> > > > literate than me and I have a 95 Dak with a 5.9! Drop it in the
> Dak
> > > > and we'll
> > > > compare notes.
> > > > Eric
>
>
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