That depends on how it is applied, the rear tire size, Hp and torque of the engine. 9" rears are tough whether big or small bearing.
If they are sticky tires, you`re in trouble. You can always upgrade a few parts to help it handle the power.
Probably won't take that much power for long, if you're getting traction. Ford upgraded to the heavier duty type 9 inch when using an engine in the 350 (approximately) horsepower range. That may have been a bit of overkill to avoid warranty claims, but it does offer some guidance. Even when running just 400 horsepower engines, many Ford musclecar guys upgrade to the nodular chunk, big bearings and 33 spline axles. I've heard of plenty of 31 spline axles breaking behind stock 375 hp 429SCJ's.
How heavy is the car?? What kind of tires?? What gears?? Full size car, low gears with sticky tires, it will break pretty quick...
IMHO 1st upgrade(&often overlooked) would be a "daytona" pinion support next I'd look at the better axles - whick will eventually drive which case you get. I personally think that the bigger bearings were more of a function of being able to stick bigger axles in there. For what you're doing - I'd be tempted to step up to 35 spline axles, 3.250" bearing case (aftermarket - Strange, Mark Williams, etc - you get "N" caps as well as the other features) and a "good" Daytona Pinion support. Yeah - maybe some overkill in there. If your heart's set on the small bearing housing - get a STEEL daytona support and the best axles you can find. Not sure what your running for internals - posi? Spool? etc.
Get an "N" case. You will break the carrier bearing caps before you break the pinion support or an axle. I had a fresh 5:67 gear on a 31 spline spool in a 3700 pound 4speed car with about 450 hp, and 12in slicks. Mix all the above with a 6000+ RPM launch and the ring gear tried to come out of the back of the axle housing.... and it almost did. Fixed that with a $175.00 swap meet Nodular case. No more problems.
It's NOT the pinion support that I'm worried about - it's the NOSE bearing - often the case will crack at the nose bearing - (BTW good place to inspect closely when buying a USED case) Putting in the BEEFIER Daytona support takes some load OFF the nose bearing allowing the case to live. Big Mike - does make a good case about the weak point of a small bearing case - that's the CAPS. Even SOME of the Factory nodular cases DON'T necessarily have Nodular Caps. That's what I was alluding to above when I said that a "bonus" when buying aftermarket Nodular cases is that they DO have Nodular Caps.
I've blown up two of them at the drags with my '68 dart. It has a warmed up small block, I dumped the clutch at about 5 grand and POW!!!
ok guys im a bit lost. can u tell me what a nodular case is or show me some photos of a nodular case and a none nodular case.
a nodualr case has a big capital "N" cast in the carrier. you can't miss it bout an inch tall. this is the strongest case for the 9". also get the daytona pinion support.
I strongly suggest you go here ... and read this ... it is a very information site about the 9 inch Ford. http://www.kevinstang.com/Ninecase.htm
Not all of them. I believe the "N" came out in late '69 - prior to that, there were nodular iron cases, but the only way to tell was the extra ribs on front. But even that wasn't foolproof as the 57-59 WAR cases had the extra ribs, but not the higher quality iron. The only foolproof way was to pull the pumpkin & check the casting number on the inside. As an aside - contrary to popular belief, the WAR cases aren't junk. Much of that was misrepresentation of statements made by Strange several years ago & repeated in various magazines over the years. It's stronger than a non-nodular case, but nowhere near as strong as a nodular case - far from junk.
The Jalopy Journal
