Factory Magnum Heads

needsaresto said
BJR,thanks for the info. How much do you think the intake could be made to flow? And if I dont have a large overlap cam will this improve or eliminate the lean condition?

Im going to slap the mags on a 318 and will be building a very streetable,hi torque, good mileage motor for a 4000 lb car with 2:94 gears. I planned on a small cam under .450 like an xe262. The heads are fresh and have brand new stock springs, and stock 1.6 ratio magnum valve gear. I will port them with the template kit from mopar. Shooting for about 9.5:1 but may need to get K.B pistons so 10:1 with them.With that small of a cam I may not bother porting. Was thinking of that in case of a cam upgrade

The less the overlap the better Tq, and cylinder pressure you'll have. And yes it will stop the leaning out of the engine. I think that with more work I really believe that they could be made to get somewhere around 260-270 but this would take a good bit of work. I'll keep playing until theres no head left to port. The key to porting is to get as much air flow and keep the port as small as possiable so velocity will stay up. I guess I should have cc'd the port after I went through each stage just to see how large the port was really getting. I may have more time to play with them this week, we'll have to wait and see.