Ford 9 inch

I don't know much about

I don't know much about 9" diffs, but I went through the Quick Performance site with the drop down boxes for options and ordering, and I was very impressed. Great prices too, as long as you live in the States, and you have that part covered. For the cost of building your 10 bolt, you spend a bit more for a really good, new 9", powdercoated and bolt into your car. Hard to pass that up.

 

Might I suggest giving GearFx as call...Highly recommended. Currie is good too. In my opinion when it comes to these set-ups, the money is going to be in the 3rd member. They are not all created equal....You will want a strong case. I have a Moser 3rd member that's a nodular iron case, the gear is US gear, daytona pinion support, 1350 yoke and the differential is a Eaton all assembled with Timken bearings. Some one these off brand are missing alot of these upgrades and you end up with nothing more than a 9" which being a 9" alone doesnt make it a superior rear. I would also say look into REM polishing or even better the US Gear Stealth series with isotropic (REM) finish.

 

580hp is nothing to worry about in a correctly built 8.5", even with a TB.

Price wise it's always up to the buyer to decide whether the difference is worth the money (both ways) just don't forget possible additional expenses for brakes and hardware.

And due to the design, a 9" will rob more ponies from that SBC leaving less to do the work if that's a consideration for you as well.

 

Call Kenny at this company and ask him what you need, really nice guy and very nice pricing ,
http://1speedway.com/index.php?route=product/product&path=81&product_id=115
then talk to the guys at Weller Racing , they build great 3rd members , and all at a better price then I could find else where, can not hurt to talk to as many as possible , to see who you want to spend your money with.

 

True, but the money you invest into a 8.5 to make it bullet proof can buy you a new 9" rear-end. I have heard that a 9" does eat more HP than a 10 bolt, but the dyno or my butt doesnt show it.

 

Just be aware that some rears with 35 splines have a bigger snout , so if you already have rims that fit they probably will not fit without mods on a 35 spline , if you go with drive plates , on a full floater rear,

 

Bought mine from Spraker Racing....great people 30 spline powder coated, mosier axles....$2800 shipped

 

Make sure when you custom the axle length, you have them build it to fit a GM wheel.