Lswhat said:The machine shop told me that the 28 oz balancer can not be used on a 50 oz motor the ratating assembly will not ballence out, because one is internally ballenced and one is externalled ballenced
.....so long as the balance on the flywheel and balancer match, you'll be ok. If I remember correctly, all 302 cranks are 'neutral' balance. The counterbalance on the balancer and flywheel is to absorb shock loads from the engine firing. The only reason they went to 50 oz was for slightly less vibration to comply with modern NVH standards. The only diff. between 289 and early 302 cranks in the stroke(2.87 vs 3.00), they only difference between early 302 cranks and late model cranks is the late models have a one-piece rear main seal. That means all the balancing stuff interchanges, so long as the imbalance of the balancer and the flywheel match.D.Hearne said:You CANNOT use a 28oz/in balancer on a 50oz/in balance motor. It will shake itself to death ( and rattle your teeth too) The cranks are completely different between the two in terms of the counterweights. The 50 oz/in has much smaller counterweights than the older 28 oz/in crank.The change had nothing to do with NVH standards, it was done as an economy move for production cost's. Also, the 5.0 designation came about in 1979 when the roller cam motor was just a pipe dream. He can use the 50 oz/in balancer by using a later model timing cover, the covers and water pumps were redesigned in 69 or 70 to the drivers side intlet for the water pump. All 289's and 302/5.0's are externally balanced.

65stang289 said:LOL super Dave I understand what you mean. I just like looking at the back end of my car and it says 5.0 HO. What is a 289 a 4.6 right or not? SO I can just get a wrecked 5.0 and switch it back to a carb motor and leave the roller cam and rockers in it then? I want a 5.0 but with a carb not fuel injections. What would you all do go with the carb setup or the injection?
Thanks for getting back to me on this.![]()