Hey guys I just registered here I'm looking for some info on my Dodge la 360 engine I read in an old motors manual that it's possible to put an early non la cam into my la engine I've had this truck for 2yrs now the motor is newly rebuilt it has a constant pooping back thru the carb that I can't get rid of every price of the motor is new except the block heads crank cam pistons etc.not rebuilt stuff brand new parts out of the box I have 30 years experience as a master mechanic yet I'm beaten by this pooping back I've tore the motor down thinking I did something wrong carefully assembled it by the Chrysler manual and still the pooping thru carb is there it idles a little rough as rpm increases pooping becomes worse to the point it won't rev any further I read the early cam will fit into the block but the engine will run badly how can I tell if I have an early or late cam? Any help would be very thank full bill. PS I've done every ck I know of comp timing removed every valve and lapped seats ck for vacuum leaks many times timing chain marks are in line adj dist air gap ported vacuum manifold vacuum replaced dist replaced ign control box plugs wires cap rotor rebuilt Edelbrock carb 2times then replaced it with a thermoquad then a qjet no difference now back to the brand new Edelbrock 600 performer I can do any type of ck or take anything apart that's needed that I haven't already done more than twice any ideas ?anyone know about the cam thing? Thanks for hearing me out I won't give up! Billv