Any chance of someone with a Cam card E-578-S

greymouser7 said

Elgin camshaft

Am looking for intake Valve closing ABDC:

I am trying to calculate for compression for this E-578-S camshaft I purchased years ago.
With 1.5 rockers
Intake .429” valve lift 209 @ .050”

Exhaust.444” Vlv lift, 220 @ .050”
I believe the website says 112 LSA Intake, 116LSA exhaust

some number: 2899206

the plan was H116 Speed Pro pistons on J cylinderheads,
Block and heads not milled.

Daily driver 360, 2.94 or 3.21 geared axle, 4K pound car.

I think this close to the 340 automatic camshaft.

Click to expand...

If the intake centerline is 112°, then the intake open at .050" would be:

112 - (209/2) = 112 - 104.5 = 7.5° after TDC = Intake open @.050"

Intake close would be:

112 + (209/2) = 112 + 104.5 = 216.5°

Now subtract 180 from 216.5:

216.5 - 180 = 36.5° ABDC = Intake closed @.050"


Now the exhaust:

If the exhaust centerline is 116°, then the exhaust open will be:

116 + (220/2) = 116 + 110 = 226°

Now subtract 180 from 226 and you get:

226 - 180 = 46° BBDC = exhaust open @.050"

Exhaust close will be:

116 - (220/2) = 116 - 110 = 6° BTDC = Exhaust close @.050"


Lobe separation will be:

(112 + 116) / 2 = 228 / 2 = 114° = Lobe sep

* this all assumes that the information for intake centerline and exhaust centerline are what you posted....