Ordering a Ford 9 inch

Looking at putting a 9 inch in the Duster and I'm a little overwhelmed with the choices so thought I ask for some help. Car is 3100 lbs with a 727 and no transbrake, 600 hp, 600 torque. So it isn't going to be super hard on a rear end but it does need to be beefed up from stock.

I'm leaning towards a Strange nodular case with S Trac differential. I think I could get by with 31 spline axles but 35 spline doesn't seem to be a huge cost adder. I'm going to use the Torino ends since they work with the disc brake kit that I'm planning on. I'm not sure about 28 or 35 spline on the pinion. So I guess it boils down to which spline count for the pinion and axles?

Seems like there are more gear choices in the 28 spline pinion while the 35 spline pinion is pro gears only. So maybe I should steer clear of the 35 spline pinion. I also see that there are different pinion shaft diameters with the 35 spline setup so that means the pinion supports are different. I can see how a person would get lost in this stuff!

I wouldn’t run anything less than 35spline axles. Torino ends are perfect, you’ll have tons of brake options.

You’ll need at least the 3.25” bore case and the 28spl pinion is fine. The nodular cases are strong, but heavy. I build a lot of the thru-bolt aluminum cases as the cost difference is negligible. With a 9” as well you can buy different length yokes so you might be able to keep your driveshaft with some playing.

Strange makes 2 different aluminum cases that are non thru bolt. One is a lightweight street type case that’s like $325. Those won’t hold up to drag racing. The other is the same they put in the Copo’s. Nice piece but obviously more pricey.

Something like this is 375.

I had a Strange Pro Iron case and it was very heavy. I switched to the Yukon bolt-through aluminum case and it makes gears changes much easier. I have two setups with different gears. I also use a Detroit locker. I had to remove a little material in the Yukon case with a die grinder to make it fit though.

Checkout Quick Performance in Iowa , they built me a custom narrowed 9" housing and 31 spline axles for my 65 . It was like $750 . shipped to my door within a week .

Thanks, that is exactly where I was going. From what I've seen so far the 35 spline axles, Torino ends, 28 spline pinion all seem to be good choices. I'll do more research on the bolt thru cases and front supports. I have a Strange 8 magnet setup on my Dana 60 so I need a pinion yoke that will accept that. I'll use a 1350 u joint. I have a Detroit Locker now and I'd rather switch to something else. I have a S Trac in my other car and I like it so I think I'll put an S Trac in the 9 inch as well.

Why are you wanting to move away from the Dana?

I've considered trying something different as well. Lockers have their drawbacks. I'm making more than 600 HP and just haven't found something that I trust to hold up, yet.

I have been building a parts list to go back to a 9" too. That Yukon through bolt case looks plenty strong and the 28 spline input is plenty strong on the pinion. My old 9 had 33 spline Moser axles and spool still making passes in a 9 second Camaro with a factory double rib iron carrier. I looked at the S-Trac for my future build but the $1000 price tag doesn't fit my budget but Cass could probably get you a better deal on that unit. I like the round back housing just because it looks like an 8 3/4. I ran the Italian made Summit brand 4.56 gears in mine and they are still going strong many hundreds of passes later. You should be able to find the yoke you need easily and the pinion support gives you plenty of options for mounting it to the housing.
Good luck with you new project I know you will like it

Gus

I'm planning on putting Weld S71 wheels on the rear to match the fronts. The offsets will be different so the axle lengths need to be changed. The gear ratio in the Dana is a 4.56 but I only need 4.10 for the way I'm using the car and I'm thinking of changing brakes as well as the differential. Rather than pull everything off the Dana 60 and try to sell a bunch of used parts I think it will be easier to just build a new rearend that drops into the car and then sell the S60 as a complete unit to someone who is building a drag race A body. I could also have a new S60 built with all the parts I want but I think the Ford housing will give me a little more room under the car. It looks like the Ford costs a little more money than the S60 but not a huge premium if I stay with bracket racer parts rather than pro parts.

While they have some drawbacks spools are predictable and reliable. About the only time I don't like the spool in my street car is in parking lots. Some people on here act like a spool will kill you in the rain, its not bad, and its predictable. A locker is more likely to come around on you when it transitions from ratcheting to locked. My Jeep has had a locker in it for 15 or so years and it wants to kill you in the rain, you just have to know when its going to make its move lol.

I don't think anyone makes a 35-spl TracLok, only a 35-spl Detroit Locker. If there is a 35-spl T-Lok, I'm interested to know who makes it.

Strange stuff is first class. The iron pro series or S series should be fine for what you are doing. They don't want the race axles used on the street. That doesn't mean guys don't do it. I would just go straight to 35 spline alloy stuff in a car that would be primarily be used on the street. 35 spline (funny car) pinions are typically used in big power race applications and are pro gear only. 28 spline is fine for most stuff below Top Sportsman level performance.

Anything you can get from Strange in a package vs. individual pieces saves a bunch of money.

I have some MW stuff that came out of my Drag Pak. But it's a spool. (You probably don't want that.) And it would probably not have the right length axles or we could make a good deal.

Had about every type rear posi you can have. The only one i hated was a Detroit Locker.

Why not a spool? I've ran one for the last eight or nine years with no issues.

Just remember a cheaply built 9 inch is no better than an 8 3/4.

There is no way I would spend money on a nine inch rear end, no matter who made the parts.
I would spend money on a 10 inch rear end with a drop out third member as long as it had over 1000 HP with a high traction chassis
I remember when the Chrisman family was developing the Ford nine inch rear end for drag racing, they used the Dunn and Reath funny car as their test mule. Joe Reath told me that they had over $2300.00 in it back in 1972 or 1973, he also said they would take it out of the car and put the Dana 60 back in it when they where racing the car in Salt Lake City, UT I didn't think to ask why they would change it for racing it up there

Lmao. Ohhhhh ok 👍

Is this a drag race or street/strip car? I use Speedway Engineering housings, but thats more suited to circle/road race. If your going custom 9", I'd go full floater. Multiple advantages such as the axle shaft doesn't carry any vehicle weight, brake pad knock back is eliminated, etc... 31 spline would be more than enough for your power level, but I'd opt for 35 to have some cushion, albeit at a weight penalty over the 31. As far as center sections, I use the iron Strange pro case (big bore for 35 spline). Aluminum cases move around a lot and eat up gears on road race/circle track applications. Same for the pinion support, iron Daytona. Differential wise, the Strange unit is almost identical to the Wavetrac, except the Wavetrac has a lifetime warranty. I chose the Wavetrac, in part due to warranty.

The S-Trac has a lifetime warranty too.
https://www.strangeengineering.net/wp-content/uploads/2016/06/File-1386772781.pdf

Exactly. And a well-built 9" center section that will handle a lot of horsepower could cost more than a Dana.
Trying not to hijack the thread, but years ago I bought a complete Dana from Strange with a Detroit locker (which I really like on the street) but I made the mistake of not ordering 5/8 studs, and it has Mopar style ends, which limit the brake options. When i ordered that Dana the motor in the car had roughly 600 hp.
With a touch under 900 hp, I'm going to order a complete new Dana with spool and 5/8 studs. The car never sees wet weather.
Looking for suggestions on which ends to go with, and a good disc brake kit w. emergency brakes.

I've seen plenty of 9" Fords $hit the bed on the starting line at dragstrip. In surprisingly light cars ,too!

Did anybody else have the feeling that this would turn into a Dana-VS-9"-VS-8 3/4 rear end argument

Gus

Might as well go all the way with a Rockwell

As long as the pinion angles right it’ll out 60’ an 8-3/4 any day.

Talk to Doctor Diff. He can set you up with what you want. He is a Strange dealer so he can order the config that you want and add the correct disc brake kit and have it drop shipped to you. If you have 15 inch wheels in back then you'll probably be limited to an 11 inch rotor but it depends on how much backspacing there is on the wheel.

And here we go.

Yeah. Even one of those can be screwed up by some hilljack who thinks he can spend $20, slap it together and send it.



And?

The S trac in my S60 works great !!!

How much do the S Tracs weigh?
A lot of people don't know how much more power a Ford type 9 inch rear end takes to make it rotate compared to any other popular rear end made in American productions cars
Every race ready Ford type rear end that I've seen or heard from racers who priced them against a Dana 60 cost any where from $500 to $1500 depending on which race parts where used on the 9 inch rear end, the better stronger parts cost more money

One of the common failure modes of the 9' is when they blow the pinion retainer out the front. So I ordered the housing from Moser that has10 bolts instead of 5 holding the pinion in. It's probably overkill, but for an extra $100 or so, why not?

I did a Strange iron case with the 3.25 bore and spool + 35 spline street axles in my Dart which is about 50 / 50 street car , race car.
And am doing a 3.062 bore Strange iron case with w True Trac and 31 spline axles for my Volare wagon , which is just a cruiser.
I have housings laying around and which ends depend on which brakes I go with.
But either of the " large Ford " ends offer a ton of options for brakes.
The only issue I have run into is shock location interfering with the back brace on the housings...........I relocated the shocks on the Dart and am still up in the air about how to address it on the Volare.

Next time at the track, go look at the rears in the 3-4 second (1/8 mile) cars. Count the number of Dana rears you see there. Look at the rears these guys are running, they are all the same type.

BTW, you won't need a pencil and paper to count the number. You actually won't need anything.

On the power rob, I really wish there was a true scientific test on a 9 inch style to see the loss. That truly would be interesting, but I doubt it would change anybody's mind anyway.

Years ago I got some great advice at the race track, "if everybody is doing it, its probably a pretty good idea"

Have a great day, I hope we get to race this year.

How can you outrun the best if your using the same parts as them
Been there, done that and then learned how to become better
As far as how to measure friction loss a good inch lb. torque wrench is your freind
Ceramic bearings will make any part rotate with less friction also

3-4 sec 1/8 mile cars?? ...sheesh...Apples and oranges...Those cars use center sections that ALONE may cost double what an entire Dana would cost. They want the 9" advantage of quickly replacing broken parts, or to dial in their cars. I can't blame them, they ARE going to break rearend parts.

Totally different than a mild street car application. And I totally understand Andy's decision to run a 9". Far more parts and options are available to him.

Regarding brand loyaly, if it is all aftermarket, who cares? My 9" doesen't have one single part that was ever in a ford factory.

None of the good race 9 inch rear ends have any Ford made parts in them, many part sellers have mad a lot of money off of these type rear end parts. A good Dana 60 will outlive and out perform the majority of these type rear ends
Money, money, money , it is your choice on what parts you buy and use

And why would that be? It’s got frictional loss as a disadvantage...

You want the lowest horsepower eater? Get a 12 bolt. Better yet, get the 12 bolt center to go into a 9" housing. Danas and 9"s aren't that far apart.

Did anybody else have the feeling that this would turn into a Dana-VS-9"-VS-8 3/4 rear end argument whistling

We run a drop out 12 bolt in the Vette, they are not the strongest but they are light and when set up correctly spin like butter

I doubt you will find many 9" gears in 3.xx door cars. 9.5's sure. As for eating up power depends on who set it up and what parts were used. You can crawl under my car and spin the yoke with by hand quite easily and it will go a couple revolutions when you stop. But as pointed out you can buy a complete whatever for what these center sections cost. Heck used they are usually right at 3 grand.

Ill second Quick Performance Aaron and those guys do great work. Aaron used to be at Yukon Gears before going to Iowa

Notice I said 9", not Ford. As far as 3 second cars go, I guess I'm talking 3 bearing pinions in a drop out.

At 2 different NSS races I saw 3 Dana's break taking out the trans with it. I'm sure those guys would have paid good money if they could go back in time and change rears. I'm running a Strange myself, but not going all that fast that I'd break a Dana. Its just that the drop out style is actually fun to work on.

You do know that a Dana even a stock one is aftermarket don’t you. Mopar never produced one. And a race Dana has zero stock parts in it.

The Strange housings that I've been looking at do not have a back brace. Looks like they build a stronger center section and then use heavy wall tubing. They do have fabricated housings but I don't think my car needs that. https://www.strangeengineering.net/product/complete-ford-9-rear-end-assembly-nb.html/

Exactly, they just share a similar design, just like the 9". IMHO, it's no different than adding aftermarket heads, intakes, cranks, rods, pistons etc.

Mopar street car, full body car, leaf spring or maybe ladder bar car. Stock eliminator - Dana is fine.

Everything else - 9".

The steel banjo housing can be braced and made much stronger than the cast or forged center with tubes pressed into it. And it makes fabrication easier.

Anyone who's ever tried to find someplace to attach 4 link brackets on 18" centers, non-parallel wheelie bar mounts, anti-roll brackets, shock mounts, locator brackets, etc, etc on a housing in a small body, big tire car gets it.

I disagree, a stock Dana 60 is a stock Dana 60 made by the Dana Corporation, correct? They are just like tires, batteries and other bolt on parts the car maker bought to use instead of making themselves on site for their exclusive use
I think the first Dana 60 I saw was in a 1957 Ford 3/4 ton pick up, I've also seen them in Chevy 3/4 tons pickups up to the 1970 model year

I don't care who did what 50 years ago. I'm trying to solve a problem today.

Here's a back braced Strange 9".

Exactly why I said 9" gears Most will be 9.5 or 10" geared centers. Not for the faint of wallet but neither is a 3 second car.

As for the Dana comments on strength. I have had them in my Valiant 9.0's at 3470 this was an S60 rear end as far as I know it is still in the car to this day. My S/ST car also had a Dana, stock narrowed housing, stock caps and a street gear. That rear end is still in the car to this day. A couple thousand laps later, with a 4 link and wheelie bars. It was 2975 and had been almost 171 all out. Neither ever broke anything. Can it happen sure, happens with 9" stuff all the time too, we have broken two gears in the dragster so far. 9" Strange bolt thru center deals. it happens.

But I don't think Andy is here to debate the merits of which is better or stronger. He needs to make a change to accomplish his goal. He does not have a car making 4 digit power so buy accordingly. If you are working with Dr Diff he will steer you in the right direction on parts selection. If the car is never going to be raced then the requirements are far less costly for something that will live a long happy life than they will be in an 8 second racecar.

Pics for attention

Well, the empty S-Series iron case is $250. The Pro Series iron is $330. The S-Series should be fine but for $80... Go with the 3.250" case.

Axles are close enough in price that 35 spline is a no brainer. Alloys should be sufficient. 35 spline posi from Strange is limited to the helical gear type or locker. Spool in a race car for sure.

Didn't say what suspension this is. I would want to have all the bracing and brackets done before putting the ends on. Or just tell Strange what you're doing and they can build it.

Again, buying a package that includes as much as possible saves money over doing it in pieces. Complete centers, axle packages, or a complete unit ready to bolt in.

The car has a Caltrac rear suspension. Split mono leaf springs with the caltrac bars. Nothing very sophisticated. I'll most likely buy the whole rear end from Strange complete with the center section, ends installed and perches welded on. Looks like they have everything I need. Pro Series nodular center, S Trac differential, 35 spline axles, 28 spline pinion, billet pinion support, 1350 yoke with speed sensor, Torino ends. Not sure about roller bearings on the pinion yoke or not. Strange offers it both ways.

Strange is very good to deal with, my S-60 came directly from them. The ordering process was painless and I got exactly what I ordered.

I think you will be good with the tapered roller pinion support. I think the ball bearing support is a little overkill for the weight of your car.

Gus

I like the Strange Ultra Case. A couple hundred extra cost wise, but absolutely bullet proof. Huge caps with big bolts, multiple pinion size options, different bearing options, forced pinion oiling, speed sensor location, 9” or 9 1/2” gear capability. Billet pinion support with multiple retaining bolts.....

The new wheels and tires are here as well as the Baer brakes so now I have all the info required to order the rear end. Glad I waited until I had all the mating parts since I needed to change some details on the rear end so the brakes would fit. I also really needed to mock things up with the new wheels and tires to get the housing width dead nuts on. Just going thru the final specs with Cass and then we'll get the order off to Strange.

The rearend will be 56 inches wide from flange to flange with equal length tubes and Torino ends. 35 spline axles, S Trac differential, Pro Series iron center section with 3.250 bore size. I'm going with 3.89 ratio standard gears and having them polished.

torino ends and ford explorer brakes, used a lot for guys with jeep builds...Tim