12 bolt or 9"ford?

[kev93]

I have a 77 shortbox 2wd with stock 12 bolt rearend. I have heard these rear ends are weaker than 12 bolt car rear ends. I am building a hi po smallblock for it. Around 425hp. Will it take abuse from burnouts to hard launches? Is there any Ford 9" rear ends that will bolt in? thanks

[smashingchuck]

I would add some c-clip eliminators if you are really worried about it, but it should hold up just fine.

[Pyrotechnic]

For that power level it will be fine. It's weaknesses are the smaller pinion shaft and the stock carrier. The pinion shaft is smaller than a car 12 but it should hold fine. Put a good posi unit in it to eliminate the stock open carrier and it will be pretty strong.

[454HO]

Someone posted in the racing forum a couple weeks ago that there is a special pinion bearing available that lets you run a car ring & pinion set in a truck housing. I never saw him post the part number though. Here is the thread -

http://67-72chevytrucks.com/vboard/s...d.php?t=346472

[Pyrotechnic]

Originally Posted by 454HO

Someone posted in the racing forum a couple weeks ago that there is a special pinion bearing available that lets you run a car ring & pinion set in a truck housing. I never saw him post the part number though. Here is the thread -

http://67-72chevytrucks.com/vboard/s...d.php?t=346472

Very interesting. I thought it couldn't be done but it looks like it very well can. Has anyone actually ever had issues with the pinion shaft on the truck 12 breaking under hard use ?

[kev93]

The size of one bearing is the only difference? Would you still use the the truck posi unit and gears???