9" or 8.5"

[lpguy]

Ok if yall had a choice between a 9" out of a f100 or a 8.5" 10bolt which would you choose.. The 9" would be stock out of a 1971 f100 with drums, the 8.5" would be stock zr2 unit with limited slip an disc brakes. 9" $100, 8.5" $300-$400

[lpguy]

forgot to add some details ill be running s10 front components and my bolt pattern will be 5X4.75 and i want to run rear discs. So those are changes that will have to be made to the rear.

[PDW HOTRODS]

How much power will you be making? What engine and trans? Would you be happy with the gear ratio in them. If a street truck the 10 bolt will be fine. If drag racing go with the 9 inch. If you need to change gears the 9 is easy.

[lpguy]

planning o. a stock 4.8-6.0. Forced induction is in the future though
Posted via Mobile Device

[Clay54]

Originally Posted by lpguy

Ok if yall had a choice between a 9" out of a f100 or a 8.5" 10bolt which would you choose.. The 9" would be stock out of a 1971 f100 with drums, the 8.5" would be stock zr2 unit with limited slip an disc brakes. 9" $100, 8.5" $300-$400

Where can you find a ZR2 for $300-$400? Clay

[OrrieG]

Will the widths work with your truck? The reason racers like the 9" is the interchangable pumpkin. Rodders like them because you can run one set of gears in town, then easily change them out to higher set for road trips. I have always understood that stock 9" is not much stronger than others and needs to be heavily modified for higher HP applications. Posi and discs is a plus on the 8.5.

[lpguy]

Somone on here is running the exact 1971 f100 rear in there ad said it was perfect width... from what ive read the zr2 may be on the longer end of spectrum but doable with the right set of wheels. car-part.com.. From what ive researched and seen on performancetruck.net firsthand the limited slip in the 8.5 rears are a ticking timebomb once you start putting good power to the ground. So either one i think would need some upgrades in the long run.

[RootBeer 6117]

I scored a ZR2 rear axle last week for $150 115,000 miles I found it on craigslist, a guy wrecked his truck and was parting it out. I have been watching car-part also for one and had a guy talked down to $250 for a rear axle. I don't intend on racing my truck or building a high HP engine.It has the same 5x4.75 bolt circle as the front and rear disc, unfortunately the guy remove it junkyard style(salvage yard they dissemble it) and cut the hose and E brake cables.
My brother runs narrowed 9" fords on a lot of his drag cars for the reasons Orrie said,I have seen one come apart but it took some serious HP to do it.
http://www.car-part.com/

Joe