1997 two door project
Good eye. 1955 F100. I had one when I was a kid. a friend sent me a Christmas card and I took that picture and sent it back to her.
I wanted to tell you what I discovered as I believe you offered past advice. All late model, 2 door, manual blazers came with a 10 bolt, 8.5" rearend and those with RPO codes GU6 AXLE,REAR,3.23 RATIO 22 G80 AXLE,REAR,POSITRACTION,LIMITED SLIP. I will most likely keep the rear axle and do my three point. Mine stock came with posi but when I jacked up the back and turned the passenger wheel CW the driver side turned CCW indicating it is not posi. I will pull the cover this weekend to see if the diff is open or Posi. the Front diff is also cast iron so i will be keeping it as well. I feel the gear ratio is 3.42 but I will also be checking that this weekend or soon. IF the rearend was replaced with an open- I will upgrade to aftermarket posi or locker. oh, and the brakes are still drum but they are a little different as well. most early muscle kits will work. mine has the square pattern without the extending bracket.
Good to know on the rear ends. You still may have a posi but it may just be wore out. I would hope for an open rear end, that way you could go with a better after market options. I did see you have after market control arms but I would still add some support to them.
It is a 10 bolt 8.5" Posi but not sure that will hold 550 hp. I have heard of this type of centrifugal mechanism and they are known to fail with horsing around with factory power. When they go chaos ensues. I guess I will need to either replace it now(save some money up) or I could run it easy next year. not sure I need an air locker so looked like a aftermarket posi is in store. www.summitracing.com
I ran out of winter... I have not fired up the new v8 and it is disappointing. I might just call it-pull and paint what I got and continue the process next year. It's time to get this on the road. How many noticed I moved the P-side wiper?



