Kawabuggy

iTrader: (1)

So I was given a "performance" cam with this last 6.0L engine that I purchased. Story goes that they purchased the cam with the intent to install it, but never got around to it and now they have sold the entire project to me. The cam came in a plastic bag with minor surface rust on it that wiped off with my finger. It came in a generic white box-and no cam card. I've checked the end of the cam for stamping but no #'s.. I'd like to figure out the specs on the cam by degreeing it, if that is possible? I've been watching videos on degreeing cams.. and that's about it. I'm sure I can figure out cam lobe lift for both intake and exhaust by just indicating off a lifter as I have the head off... I think I can figure out .050" lift duration for each lobe as well by simply putting a dial indicator on the intake, then exhaust, valve tip for #1 cylinder, then rolling the motor over until the rocker opens .050", mark the # on the degree wheel, and then continue to roll the motor over until the valve comes back to .050" before closing and record that number..I have a head I can pop on for the valve reading. Then, I assume I can do some math to figure out what the duration is... LSA? That one I'm still stumped on. I've also seen on some videos where they are recording the # on the degree wheel at various intake valve opening points such as .006", then .020", or .026" then .050".. Which valve opening points should I be checking? I have this cam installed in an engine with just the #1 piston installed-all other holes are empty. I've already got the degree wheel installed, and have already found TDC for #1. I've got the BIG 18" Moroso degree wheel. I'm starting with the dots aligned as you normally would. Any body want to guide me along this process? I can post pics for those that want to follow along to see how this is done if there is any interest.

Kawabuggy

iTrader: (1)

Came up with lift on intake lobe at cam is .324 x rocker ratio 1.7=.551"
ICL comes up as 111.. now...on to duration...
Anybody have a clue as to how to determine LSA?


intake valve .050" before peak 71.5°, then .050" after peak lift 151°= 151+71.5=222.5/2=111.25, or 111°

G Atsma

Locate lobe peak on exhaust, then measure degrees until intake peak.

Kawabuggy

iTrader: (1)

exhaust valve lift @ cam .324 x 1.7 rocker ratio=.551" lift
exhaust valve degrees at .050" before peak lift 150°, then .050" after peak lift 67°=150+67=217/2=108.5

Moving on to duration #'s on both the intake lobe and exhaust lobe next.

theunderlord

"To check your LSA you calculate it by adding the intake and exhaust Lobe Centerline figures together and dividing their sum by two (Ex: 112 intake Centerline + 116 exhaust Centerline = 228 / 2 = 114-degree LOBE SEPARATION ANGLE)."

Searched around and found that, seems pretty straightforward?

Kawabuggy

iTrader: (1)

thanks underlord... with that math, i come up with Intake center line of 111°+exhaust center line 108.5°=219.5/2=109.75 rounded up lets just say 110 LSA. Since I have no cam card let's hope that's what it's supposed to be. Now, how does the cam having ground in advance come into play? Also, since I'm moving on to duration... how many thousandths of an inch should I consider the open/close point .005'? .006"?

Kawabuggy

iTrader: (1)

duration @ .005" lift 67° open for the exhaust valve + 27° degrees closing (using .005" for both open and close points)= 27° + 67° degrees before TDC +180=274°
duration @ .050" lift 141° open for the exhaust valve + 1° degree closing = 39° + 1° +180°= 220°

intake
duration @ .005" lift 22° open for intake valve +116° closing = 22° + 64° + 180=266
duration @ .050" lift 5° open for intake valve + 142° closing = 5° + 38° + 180=223

So... if I've got this figured all correctly (which I will probably never remember again.. This cam is;
.551" lift both intake and exhaust with 223°/220° intake/exhaust @ .050" lift on a 110LSA

Anybody have a feel how this cam might work in a .030" 6.0L with pocket ported 706 heads with 2" intake valves, and a head gasket that is 4.040" bore, .041" compressed height, with true flat top pistons with no valve reliefs? Let me go find a compression calculator to see what the static compression is... then I can check dynamic since I have my intake valve lift open and closing points.

Summit racing compression calculator says 11.6:1static, with a dynamic compression ratio of 9.99:1