OK, We picked up that roller motor that we built that tossed a rod...moving on, today I was tinkering with the heads and cam that we removed from that longblock we bought, I got to looking at the cam (I had assumed it was a stock HO Roller out of a Mustang GT and had low miles) and I hold the cam we took out of the longblock we bought and held it up beside our X303.................something looked really similar, way similar so I got out the micrometer and guess what I do believe the motor was running a Z303, the centerline and lobe angles are identical, the lobes on our X303 measure right about 1.683 at peak and the lobes on the cam out of the long block we bought measure right about 1.713.....the only identifying markings to be found were "ZZ" right past the disty gear and 941431 on the back end of the cam, I have tried to find a cam using those identifiers to no avail. Also I thought that once you got above the B303 it required considerable valvetrain work however I found in my study that the factory heads with factory rockers can handle the Z cam with a spring change. Can anyone tell me if they know exactely what cam this is, because if it is truly the Z then I have a pair of heads that have had some work, springs at a minimum and I have a Z303 in excellent shape...thanks in advance.
Z303 cam specs for anyone interested. Cam Style:Hydraulic roller tappet Basic Operating RPM Range:2,500-6,500 Intake Duration at 050 inch Lift:228 Exhaust Duration at 050 inch Lift:228 Duration at 050 inch Lift:228 int./228 exh. Advertised Intake Duration:290 Advertised Exhaust Duration:290 Advertised Duration:290 int./290 exh. Intake Valve Lift with Factory Rocker Arm Ratio:0.552 in. Exhaust Valve Lift with Factory Rocker Arm Ratio:0.552 in. Valve Lift with Factory Rocker Arm Ratio:0.552 int./0.552 exh. Lobe Separation (degrees):112
http://www.svtperformance.com/forum...er-see-the-samping-on-a-stock-94-95-Cobra-Cam It's a ways down the page
Yes I have the cam card that came with our X303, what I am trying to find out is what cam is in the roller motor we bought, according to the link provided by JoeB it's a stock GT cam BUT is a stock GT cam have more lift than the X303? what info I have found says stock cam is .440"/.440" 210/210@0.50, the X303 IS .542"/.542" 224/224@0.50 now the cam that came out of the motor we bought while having the ZZ marking, the lobes are bigger than the X303, would that not mean more lift?
Sure looks to me like Joe set you on the right path there. How exactly are you measuring the total lift on this cam? Easy old school way is to just subtract the flank size(side to side) from total max lobe lift(base to peak) and then multiply by the factory rocker ratio(or whatever you're using). Two cams that have identical peak numbers can be quite different due to variations in flank size. Small base circle cams are good proof of that. And even tiny nearly invisible differences in "over the nose" widths can mean large variance in duration numbers.
