what universal joint part # to use stock driveshaft with a 12 bolt
 

tried 358 and a 447 and neither work

If you are using the stock driveshaft with it's 1310 yoke and a 12 bolt with a 1350 yoke, then Napa pn# 240-0447 is what you need. Bob

thanks bob i think they gave me 210 0447

If you are running a 12 bolt then you should probably upgrade the shaft too. PM me for details on a 3.5" shaft good for 1000+hp.

How much abuse will the stock shaft take???

In a stick car? Not much. Guys break them with bolt ons easy.

Can we be more specific - I have numerous H/C passes on my stock shaft with a 10 bolt, but I am switching to 12 bolt next week.

No offense, but I would like to hear from someone who doesn't sell DS's :)

I have seen them break on many occasions once the car hits 11s. Search in this section. Auto cars are usually OK to 10s if the car is light. You must not be running very quick or are slow out of the whole to be able to run your 10 bolt and stock DS with H/C.

Well, I blew the 10 bolt once I started to push the car (12.4's coasting threw the traps with busted rear) - I do not have any passes since.

I am just trying to answer your question and help prevent damage to your drivetrain.
Here are two example in the last month or so who had problems.

https://ls1tech.com/forums/showthrea...ght=driveshaft

https://ls1tech.com/forums/showthrea...ght=driveshaft