Camshaft selection choices

[Bugsmasher]

Just ordered an Engle W-110 cam and some other goodies. I hope that this is the cam that gets the most air miles on. I also ordered a set of lifters with the oil hole in the bottom for extra cam lobe lube. As I will only need half the set...the other 4 will be for sale when I get the package of goods. I will post in for sale section. Any comments on cams in use or suggested cams?

[Steve]

I have a couple engines with the Engle 110 cam in them - it makes power but has a harsh exhaust note and the idle is best at 1050 rpm... The higher idle does not pull the plane so Ok... As Leonard says on the 1/2's, idle 1000, taxi 2000, fly 3000... I like to see a minimum of 3200 static because I'm over gross and often in density altitude considerations... The 110 on #33 69x94 with duals (EI & Carbs) static pulls 190 lbs on a Tennessee 54x20 at 3350 rpm... Tim Floyd has an Engle 100 on his 69x92 and likes it - idles real smooth...

Scott Casler & Steve Bennett are putting out engines with different performance cams - I think maybe Sam Buchanan or Joe Spencer have some info on that...

[flydog]

Steve
is that 190 lbs thrust with a 1/2 VW?
If so I'm wow-ed.
Thought I saw somewhere numbers much lower than that.

[Bugsmasher]

So what are Scott and Spencer doing cam wise if they would share? I did change the cam to the Engle 100 for a lower duration before they shipped parts. The cam as advertised  420" Valve Lift (1.1 Rockers), 276 degrees duration. Seems a stock cam has .334" lift with 1:1 rockers. Interesting study of these cams offered by vendors.

[Steve]

Steve
is that 190 lbs thrust with a 1/2 VW?
If so I'm wow-ed.
Thought I saw somewhere numbers much lower than that.

http://groups.yahoo.com/neo/groups/EaglersNests/database/11/records

Scroll down to September 1, 2004 heading:
http://www.angoraaffaire.com/leu/id67.htm

Test was done with a certified scale and an engineer observer... Steve

[flydog]

Just thinkin out loud.
Has anyone experimented with advancing the cam timing to lower the RPMs of peak torque?
What if we could move the peak torque/HP down to 2700, 2800ish?
Then run a larger diameter/more efficient prop?

[Steve]

According to Bob Hoover the torque peak moves down 200 rpm for every 4 degrees of cam retard... On his Chugger motor he was planning to retard a stock cam 4-7 degrees...

I've read elsewhere that the Engle 100 & 110 cams usually measure 2 degrees of retard...

There are some 1/2 Vw's now running with the HVX mod's but I don't know if the cam timing was modified...

It's real easy to put too much prop on a 1/2 and get stuck with a static rpm around 2900... If you hook up a manifold pressure gage you can figure out if that's the problem... I think Steve Bennett of GPAS looks for no more than 24" of pressure... I think his number there has changed over time so a call to confirm current thinking is in order... Bennett in Forums has always said that too much prop is the reason for most early engine trouble calls... 

A static rpm change of 200 rpm makes a huge difference in aircraft performance...