Name That Cam

[73_Cuda_4_Me]

Starting the 73's rebuild on original engine, measuring cam before tear down, and come up with following on dial indicator... Doesn't match any spec for 73 small block of any kind in my manuals... Heads are off, TDC confirmed with timing mark on 'external' balanced harmonic dampener, with pistons .085" below deck @ TDC. Degree wheel and pointer wire used with mag mount 1 inch dial indicator and 3 lifters stacked and racked for measurements in line with lifter bores...

@.006 lift: Intake opens 23 BTDC, Closes 84 ABDC Duration 287    Exhaust opens 73 BBDC, Closes 40 ATDC Duration 293   

@.050 lift: Intake opens 10 ATDC, Closes 40 ABDC Duration 210    Exhaust opens 44 BBDC, Closes 5 BTDC Duration 219

Intake lobe lift .244 @ 116 ATDC  (.366 total @ 1.5 ratio)
Exhaust lobe lift .292 @ 68 ABDC (.438 @ 1.5 ratio)

Soooooo.... Anyone have any idea what the cam could be from? Only ID I can find on cam is a "D16" on a cast pad by distributor drive gear... does not match 318, 340, or 360 specs...

[cudabob496]

some Comp cams with  .438 lift on this page


http://www.jegs.com/webapp/wcs/stores/servlet/KeywordSearchCmd?storeId=10001&catalogId=10002&langId=-1&Ntk=all&Jnar=0&itemPerPage=60&Ne=1%2B2%2B3%2B13%2B1147708&searchTerm=.438

[Chryco Psycho]

Factory cam was split profile .440 lift , .366 is too low for any cam I am aware of .

[73_Cuda_4_Me]

Thanks Cudabob and Chryco!

Chryco - I checked lobes for wear to see if that was throwing off the readings (because it ALMOST looks like the factory spec), but lobes look good, and all read same amount of lift (intake vs intake, exhaust vs exhaust). The durations do not match with factory spec as well at either .006" or .050" lift. Lobe width is narrower than the cam that came out of the 70 engine, so probably for 3/4" diameter lifter?

Just out of curiosity, how do you think that cam would be for street use? Looks to me like a low-end torquer, high-mileage, smooth idle, high vacuum type of cam? My initial thought was maybe a cam out of a Mopar small block truck?

[Chryco Psycho]

I would replace the cam , you can get similar duration & be in the .470 lift range with a Lunati Voodoo series cam

[73_Cuda_4_Me]

That is the plan, Chryco... just documenting everything thoroughly on teardown of the original 340 engine... a couple of burned exhaust valves, some bent pushrods, rocker shafts installed upside down at some point in time (can see wear on top of shaft where rockers were riding at some point, but correct when removed), a couple of cupped lifters, stock piston bores so far, and numbering rods and caps so I can mic the bearing journals, etc... it is kind of interesting reading the history of the engine just by inspection, measure, and observation.. HaHa!