Looking for help with a new rearend.

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Cope

Cope

Fusing with fire
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I picked up a Ford 9" for the drag car and need some help.

How do I figure out pinion angle?
Do I want to weld on the four link brackets at 90 to the pinion or am I gonna want them at a slight angle for pinion angle?
The 9" has the pinion a few inches to the side of the pumpkin, do I want to center the pinion in the car and use pinion angle up or down for the u joints?
What's the best way/method to weld to the axle tubes?
Any and all help would be great, Thanks again.
 
Cope,
Usually I mock up everything under the car at ride height, set pinion at 1-2* down with the left upper bar. Many will start with 4 bars all equal length then weld the brackets where the are happy with everything aligning. This gives you the same opportunity to make sure you have proper shock and wheelie bar clearance.

Now with that being said, many will weld the 4-link brackets as you described, parallel to housing flange face and be real close. I like to tig, but mig or tig is fine.

The housing ends should be the absolute last thing welded on. Use the Ford 4 bolt new style ends. You have tons of brake options and they use the std 2.5" brake offset.

Measurements: a 9" pinion is mounted 0.970 to the passenger side and 2.25" down from axle centerline when viewing the carrier from the front. Usually you leave about 1.25 to 1.375 as the space between the axles "inside" the spool/diff. If you center the pinion the drivers axle will be 4" shorter than passenger.

Many people will center the housing as it gives plenty of room to weld brackets on both sides and visually looks better from behind the car.

You can center the pinion, center the housing, or run equal length axles.

Good luck.
 
Just as an FYI too. I get quite a few things from quickperformance.com in regards to back braces and misc stuff.

Cass(DoctorDiff) is great too. I buy a lot of his axles plus he can get you anything Strange related as well.

If you're going to run a heavy hp car consider going to an 3.25 or 3.89 carrier bearing case. Then you can run 35/40 spline and it'll live longer.
 
Thanks.
Im just gonna make the back brace but Ill take a look and see what they got.
The rearend is a big bearing rear, Its huge.
You can bet Im gonna do my best to break this one! Pops always said I coud F#ck up a steele bar with a rubber hammer!
 
Be careful welding on the brackets. It's very easy to bow the axle tubes. I use a bar/cone set-up that goes through the tubes to keep them straight, especially when welding the ends on.
 
I was gonna stich weld one inch at a time and cool the welds with compressed air. My TIG is still in tahoe so im just gonna use pops MIG.

My fear was that the tubes are some chincy metal and would nead a specific rod?
 
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