Hi there peoples i have just fitted at 302 clevo with lumpy cam flattop pistons 465 holley card mech secondaries when u start up it fine but once goes into drive or any gear she slows down and stalls the car will run under high revs no problem could this also be fuel pump its a standard pump on side of motor ,or carby problem

Lumpy cam = low vacuum which causes the power valve to fluctuate at idle when in gear. Take vacuum reading at idle BOTH in gear and out of gear, if the vacuum reading drops below the opening point of the power valve install a lower reading valve.
This is a standard treatment for holley carburettors on big cammed motors

It could be either. If it is a lumpy cam you might find an out of gear idle might have to be as high as 1000 revs to compensate for the reduced vacuum etc. and also big cams usually require more advanve. try setting it at 12 degrees and go back in half dgree increments if you experience pinging. Whe you have exhausted all other avenues start aking yourself about the cam install. it is not unheard of for cam manufactureres to have the locator pin a poofteenth out. If this happens the off beat valve timing will do just that. Pull a plug gently rest a thin screw driver or something on top of the piston and turn by hand back and forth past the TDC mark on the balancer untill you are sure it is top dead centre and then refer to the balancer and mark it if it is different to the TDC mark already there. Rotate 180 dgrees and with the rocker cover off remove a rocker and set up a dial guage on top of the push rod. While someone rotates by hand to TDC check the guage, your cam specs which the manufacturer can or already has given you will have a nominated lobe lift at so many degrees before tdc or at tdc. repeat it a couple of time and if your not at the given value then you would need a multi keyed timing sprocket. My last big cam i had to advance the cam 4 degrees. This is all a lot of hassle to go to after wards ideally the cam should be degeed on install so this would be your last port of call. Go the ignition timing and carby first.

Yes quite agree about degreeing in when fitting a cam.
Have you got the specs on the cam as it would be easier to diagnose

Hi guys thanks for the info well we started back to basic my nephew said the timing was incorrect so he reset it and changed carby now she runs pretty sweet next thing to do i off to the dyno shop i think that will be the best idea to get it 100% now