Rear End Swap Question

Hi, new to the forum. Recently purchased a Saxon built by Steel Roadsters. Car has ford 2.8l v6 with 4 speed trans and chevette rear end. Looking to swap out to a 5 speed and a 8.8 or 9 inch rear end with coil over shocks. My question is does anyone know the purpose of the differential adapter that is part of the original build. All my googling shows results for heavy vehicles. From the build manual "Secure the differential adapter to the differential with the 4 bolts which previously secured the torque tube to the differential." If I swap out to new rear end is this part still required?

Hi Ben, welcome to the Forum.

Haven't seen a Saxon with a Chevette rear and it's not in my build manual, but it sure seems like you won't need it. With a different rear end, transmission, drive line and suspension there is nothing to "adapt".

Hopefully, some Saxon owners will chime in here.
Finding a doner rear end in the correct width will sure make it a lot easier.
And...in an effort to save you some time and money...unless you're running 400 plus horsepower and 10" drag slicks, you sure don't need an 8.8 or 9 inch. (just my .02 cents.)

Hello Ben,
I don't know if your car was built like mine? My Saxon was built in 85 with all chevette running gear, it had a torque arm bolted to the center of the differential housing and spring pockets on the end of the axel tubes. I ended up with a Ford 8.8 rearend. I narrowed it 8", 4" per side that allowed me to use an 8" 0 offset rim. A 6", 3" per side might have been a wiser move. I agree with Jerry, If you are going to an 8.8 or a 9" you will need to narrow it, also thats probably going the easiest part of the project, you will have to cut out the old suspension and relocate the shocks on the frame, you will also need to figure out how your shock/trailing arm mounts are going to work.
But thats what makes it fun... Saxonford.

Thanks for the info. Right now I'm looking for the best option. But it needs changing.

Ben, I think the part in the manual described as "the adapter" might be the part the Torque Arm is bolted to? The F-body camaros used 8.8s with a torque arm - they also have disc brakes - this might be a good choice for you? it would allow you to use your existing torque arm and trailing arm mounting points on the frame. Just some food for thought. Saxonford

Correction: The 3rd and 4th generation F-body camaros used 8.8s with a torque arm.

Sorry, but the 8.8 is a Ford rear. The F bodies used mostly 7.5 GM corporate rear ends.

I

Opps... I admit I have only a passing acquaintance with these, I was just trying to come up with rearend that used a torque arm to help Ben.
my apologizes to Ben and everyone else. Please ignore my posts. I defer to Hotrod.
Saxonford

Hey, don't let me chase you away.  Didn't mean to offend.  Just trying to pass on good info.  I was in a hurry when I posted that and didn't intend for it to sound harsh in any way. Apologies if it did.

I know there were Saxons with Chevette running gear but have never seen one.  A few pictures of the current rearend would be helpful.  

Just a guess but it sounds like CR might eliminated the torque tube in favor of a conventional drive shaft.

FWIW - GM did make an 8.5 rear and it is possible that they were installed in some higher horsepower F bodies.  I know some S10's had the 8.5 and they were fitted with disks. Very few cars were ever fitted with torque arms.  The F bodies are the only modern cars that come to mind.

Struggling with posting pic. bottom line in needs to come out. There is evidence of it striking the body. someone in the past even cut a small piece out to try and prevent the hitting. Thinking of going with 7.5 rear end from a mustang II. The engine is out of same .

Ben,
My conscience won't let me stay out of this discussion, seeing the picture reminded me of my car. My car was built like the one in your manual, with a 2 inch square tube frame. I hope your car was built with the larger rectangular frame. If you have a 2 inch square tube frame you should perform this test. Support your frame on jack stands just in front of the rear wheel, so that the back wheels are off the ground. Place a 2x4 on end on the frame just behind the gas tank and slowly jack up the back of the car and look at the door gaps just behind the door handle. I you see a lot of movement it means your frame is weak and you may have more the just a rear end problem.
Good luck, Saxonford

Thanks for the heads up. Checked and my frame is 3x2 rectangle. Have to ask, what did you do to correct your issue?

I'll answer that for SaxonFord. It might sound like he's bragging, so I'll do it for him. He fabricated a really super cool tube frame that strengthened the whole car.
Here's a link with pictures.
This is very beneficial IF you're running a bunch of horsepower.

[You must be registered and logged in to see this link.]

I'm glade to hear you have the better frame. I welded a 3-1/2" x 2" U shaped section along the bottom of the frame. I have change almost every thing on my car.
Saxonford