I will be converting to a 5 speed transmission. I'm running a strong 454 and will need a new driveshaft when completed. I realize that if I were to upgrade from 1310 to 1350 Ujoints this would be the time. I really don't want to if it is not a real requirement. I replaced my factory 12 bolt gears with Richmond 3:55's and don't want to disturb the pinion. I plan to go to the strip a few times but I don't think I will ever put slick on or get too serious. Will Spicer 1310's hold up?

I would think that on street tires the 1310's would be all that you would ever need. Score some without the grease zerks, story goes that they are stronger. The tires will act as "shear pins" and go up in smoke long before you over stress the joints.

I just went thru that decision. You may want to split the difference and go with the 1330 Spicer. I went with 1350 front Spicer yoke and 1330 rear. The guys at Denny's helped alot.