Alessandro wrote:

lowercasesteve wrote:

Alessandro wrote:

I should explain me better my mistake !
I have found one center section 9 inch 28 spine and one axle case 9 inch .resonable price .
Just wanna know if my 28 spline axes could be re used but i think had the same answer . no mix
Ok i will search something , no problem for welding here !
Thanks

Not so.  It gets a little complex, but... 
If your 8" axles have the same spline count as the 9" center section, then they will work together just fine. In your case both have 28 splines, so no problem.  And, if you don't bang shift the trans, the 28 spline axles are strong enough for your application.

The 9" housing must have the same width as your current 8" housing.  It can be shortened by a competent shop.  Do not try to do it yourself unless you have excellent fabrication skills. The spring pads must be repositioned to that of the 8" housing. (new ones can be purchased from most any Mustang house.)  The cutting and welding will throw the housing out of alignment, so you must re align the housing after each weld cycle.  The alignment process requires some special tools to make sure everything is correct.  Don't try it yourself.

And, finally, The axle bearing size must match the 9" housing bearing size.  9" axles came with two different bearing sizes.  They are very different, so you will know when you match them up.

To summarize.  The good news is that the 9" housing can be shortened to the size of the 8".  And if the bearings are different sizes, the end of the 8" housing where the bearing races are can be grafted on to the 9".

Alessandro,  it must be tough having this conversation with numerous Americans in a different time zone and using a language that is not your first language.  You've been doing a great job though.
 

Wow ... It' quite huge job .
what you say is right and find capaple welder is not a problem ... But only to re use the axel and find right bearings to adapt something ....
Mmm... I Need to think it twice before i begin start something .
I havent leave the option to upgrade only the 8 inch with LSD .
work with less hp first request it will last for my week end cruising .

Btw yes ...sometimes is really difficult . mostly because meaning and way of saying are untranslatabe .
But here i have found people with patience and passion .
Thanks for help !

Actually, it is not that bad.  Basically, you shorten the 9" housing using the 8" housing ends instead of the 9" ones.  But the housing realignment must still be done.  The 8" axles will fit right in.

If you have access to the magazine, Street Rodder, the November issue has a do-it-yourself article on this very subject.

Last edited by lowercasesteve (9/17/2016 4:45 PM)

Alessandro wrote:

MS wrote:

For the four speed, the 3.50 gears will be pretty steep, and nearly unbearable .

The google translator dont help me so much  but  what you mean  pretty steep ?

here in italy we use a different way to speak that  .
 we use LONG gear to define a slow rev thru gears with high top speed . for example 2.80
a SHORT gear to define a fast rev thru gears with low top speed with high rev. for example 3.55
Sometimes is difficult to transate saying, hometown meanings or akronimus  and sometimes also the easyest word become hard to understand.

 

Steep = short.  You will rev too high with the four speed cruising the highway.  But with the T5 you can go "short" and still not rev too high.  I have 3.70:1 and a five speed.  Does around 2,200 RPM at 70 MPH.

MS wrote:

TKOPerformance wrote:

So there were 8" rears that used the same axle bearings as 9" rears?

ALL factory equipped Mustangs from 65-73 used the small bearings.  Axles do interchange between 8" and 9" on 28 spline cars.

I think it was Torinos that had large bearing axles.  Alessandro could have a housing from anything.  No telling whence it came.
 

That housing would work with your existing axles then, just get the small housing ends.

I'd try and find a center section that already has what you want in it, I think you can find one cheaper that buying one that has an open differential and the wrong gears and then swapping those parts.  Also, if you don't know how to set up gears you've got to factor labor into that too.  It isn't a simple bolt in situation.  Quick Performance sells the center section optioned with a clutch limited slip and 3.70 gears for only $820.  I would just buy everything from them.

You know...We have a member on this site - Haken - who lives in Sweden.  He has lots of contacts around Europe.  Maybe he would help you out finding parts.

there are a couple of guys in England too I believe.  But I do not know their names.

Its really about where the fuse is.  In the drivetrain what fails first is what determines what will live.  In a street car the tires are typically the fuse, because you will lose traction before you can shock load anything enough to break it.  The problem is that works great in 1st and 2nd gear, but keep hammering on it and most cars will have traction in 3rd gear, and then its a question of what's going to break.  Now, if you can back off of it in 3rd you can probably make it live, so sure, driving style is important in that sense.

This is the most important thing to understand about drivetrain strength: there's no hard and fast rules.  In an engine I can tell you with a given amount of airflow it can only make so much power.  That's the whole idea behind restrictor plate engines; they all make the same power because they all have the same airflow.  With drivetrains the question is always how much power can it take?  The real answer is: no one knows.  I've seen guys run rears and transmissions they shouldn't and have them live seemingly forever.  I've also seen guys break tough parts with stock engines.  Its about where the fuse is and how you drive, but its also luck of the draw sometimes.  My motto is simply that its better to be safe than sorry.  Largely because I haven't had good luck living dangerously over the years. 

Exactly what I was trying to say!  The Explorer has the 8.8" rear, which is pretty stout, and even more so with the 31 spline axles (5.0 Mustangs had 28 spline axles for years).  If you check that tag on the rear cover and see an L it has a limited slip.  I'm not sure about gear ratios, but that will be on the tag too, and I would bet most Explorers had 3.xx:1 gears, some probably had 3.73s, particularly if they were equipped to tow. 

Bullet Bob wrote:

I just tuned into this thread and haven't bothered to read all sixty posts but...since you seem to be discussing rear axles, are Ford Explorer parts any easier to find over there than early Mustang parts?  The 96-2000 Explorer rearend is easily modified to go under a 65-66.   They are easy to set-up and are plenty strong, from what I can determine, with 31 spline axles.  And, they have disc brakes in the deal and many have traction loc.
Just sayin'.

BB

 
Thanks for info but , the 9 inch is come out as a suggestion to handle an high  power engine matched with a t5 trans .
Due to budget and massive shipping and duties cost i Need to review the all thing.
Not always is possible to  buy the top notch spare parts .
The explorer axle is one that i have put my eyes on , but unless i found it right here with few money ( and i dont believe it )  is only the beginning of cut and weld .i
i prefer not to do this kind of job because i have a lot to do on other part of the car .
I Need to be focus on what i am doing because i got too much meat on the grill !
Thanks !

Alessandro,  You're da man!  Keep up the good work.

I love this conversation we all have been having.  You ask good questions and give us good feedback.  You seem to think while writing.   We can feel your frustration and anguish trying to get parts and information.  Keep us up with your build as it progresses. 

lowercasesteve wrote:

Alessandro,  You're da man!  Keep up the good work.

I love this conversation we all have been having.  You ask good questions and give us good feedback.  You seem to think while writing.   We can feel your frustration and anguish trying to get parts and information.  Keep us up with your build as it progresses. 

 
Thanks Steve  , for me is a huge opportunity being here .
I Take all suggestions and try to make real this dream . Now with some issue i got cleared my mind and Take the good road .
Belive me it' s a long story before i could say finally is on the lifter !.
On my side i got some mechanical skills from my past job , so until now no problem . As always unbuild  is easier than build ...

Thanks you all guys