Cam specifically for 5L stroker motors.

[Bluegrass]

Comp Cams has a new line of roller cams for stroker motors that are optimized for the difference in piston speeds at top dead center and bottom dead center due to the change in rod ratios.
I have been into this sort of thing some years ago and only custom cam vendors were doing this on a private basis.
Check out their line of XFI cams.

[eVole420]

cool, ive been thinking about messing with the top end of my new LSC but been too poor round Christmas time :) Got a link for me?

[Bluegrass]

Competition Cams Website has the cam listings in the new products catalog for 2006.
The reason the cams are a bit different in profile is the difference in dwell time of the pistion at top and bottom centers due to the rod length changes as well as the larger displacments.

[mark007]

hey blue whats your take on a cam for a blown stroker motor. some feel that the stocker is nice and some in favor of off-the-shelf. i already have mine installed and whatnot but not really sure ablout it. its a kennedy'sdynotune custom cam for a kenne bell, but i think my heads are more than the cam might be designed for.

[Bluegrass]

....As the displacment increases above 5L, the same cam's performance peaks lower in the rpm range and tends to become a torque monster in compairison to the stock application as well as limiting top end hp from cam duration that becomes a restriction.

....It is better specifically cam for the larger displacment with an eye on very low amounts of overlap less than about 15*in most cases.

....Heads need to try and favor high exhaust flow even if larger exhaust valves are installed with stock intakes, and exhaust porting is done along with headers and enough system flow.

....This is getting very specific but are some of the ways to optimize the setup.
....Since the engine is being force fed, the cfm in equals the cfm out.
....The only difference is the temp and speed of flow plus conversion by combustion.
....A motor sprayed is nearly the same as super charging except for the difference in intake pressures. The amount of exhaust flow is quite high over just gas fuel due to the extra oxygen added with extra fuel from the Nox supply system.
....If you study Comp Cams profiles for this use, you can see these parameters in practice.
....Up till just awhile ago the cams never took into account the longer rod effects but are now geting into that areana.
....A few degrees here and there at the right points makes quite a difference.
....Another way to get an education on the effects of this is a simple software dyno program just working with cam profiles on the engine of interest.

[mark007]

....As the displacment increases above 5L, the same cam's performance peaks lower in the rpm range and tends to become a torque monster in compairison to the stock application as well as limiting top end hp from cam duration that becomes a restriction.

....It is better specifically cam for the larger displacment with an eye on very low amounts of overlap less than about 15*in most cases.

....Heads need to try and favor high exhaust flow even if larger exhaust valves are installed with stock intakes, and exhaust porting is done along with headers and enough system flow.

....This is getting very specific but are some of the ways to optimize the setup.
....Since the engine is being force fed, the cfm in equals the cfm out.
....The only difference is the temp and speed of flow plus conversion by combustion.
....A motor sprayed is nearly the same as super charging except for the difference in intake pressures. The amount of exhaust flow is quite high over just gas fuel due to the extra oxygen added with extra fuel from the Nox supply system.
....If you study Comp Cams profiles for this use, you can see these parameters in practice.
....Up till just awhile ago the cams never took into account the longer rod effects but are now geting into that areana.
....A few degrees here and there at the right points makes quite a difference.
....Another way to get an education on the effects of this is a simple software dyno program just working with cam profiles on the engine of interest.


okay that said i would find the program where, and is all i need to do is input the specifics of my cam and what not.is that correct.

[Bluegrass]

For educational purposes only and some reasonable idea of what can be expected of an engine combination with what inputs built into the program; the DESK TOP Dyno at about $40 is a great tool to see what the basics will tend to do when parmeters are changed.
The direction of change is usually very reliable but the real life results are always subject to to many variables with the combination as a whole.
Only the high end programs can come very close to the real results although this little program can get pretty close.
The program is carried by Auto Zone and Advance Auto in my area.

[macx]

Awhile ago I ran into a magazine article
about a shop that builds hi end motors,
like I think for Nascar even, and has gone
into the hi end crate motor business.

Thought I had the bookmark, but I've
literally got a couple hundred just for
Ford/Lincoln stuff and don't have them
sorted very well.

I know it was in some magazine, I'll look
for the article. Very enlightening.

The article was about optimizing a stroker
351W (393), and a big point they made was
getting the right cam. They used the below
service. Of course, it's a one time per purchase
but it's supposed to be the real deal on cam
selection.

In the meantime, till I find the parent article,
here's the cam program they used.


http://www.davidvizard.com/camshaft.html

http://www.davidvizard.com/FORM.html

[1LapLSC]

Thanks, Blue...

I'm makin' notes...

Wiley