A Body swap with E body 8 3/4 with 4link

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illrad91

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Hello guys I'm new to this forum and ok with my Mopar knowledge. Anyways I have a 1967 Dodge Dart original v6 and I wanted to change to GTS gerst 4link with the 8 3/4 E body I just bought. The 8 3/4 rear is complete with 3.23 and 12" drums but idk what id need to do to fit the rearend in My A Body dart. Also what kind of 8 3/4 is it? Looks original rear end with the 12" on them with lines and brake line also but idk. So please if you guys could help me I honestly don't want to shorten the 8 3/4 but if I have to what are the top of the line internal axles to get?

ThNKS a lot everyone and I hope to hear from you guys

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It's about 5.1" wider at the flange dimension, so a little over 2.5" per side. You'd end up with heavily positive offset wheels looking gross, resembling a front wheel drive. A 66-70 B body rear housing is a much better fit at an 1.5" less, and a perch difference of only 1". Still requires welding in either case.

A nice Ridgid pipe cutter, a square and a welder are your friend.

Moparts on the Web - Main Index

Oh, by the way, welcome to the forum. Show us some pics of that V6 Dart, I know I'd like to see it.

:lol:
 
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I believe the A dimension is the bare housing flange, with the backing plates removed.
 
I hate to be this guy but, you're in trouble with that rear end.. it's too wide, so to do it correctly it really needs to be shortened, the seats will need to be moved and you'll have to coin up for custom axles.. (Moser, Strange.. ) which may make you realize you want rear disc brakes, which may require a brake system upgrade. BTW, do you need e-brakes in your state? I see the original cables - which probably won't fit your Dart (I don't know for sure, just thinking "Murphy's law") even if you stay with the drum brakes.
You're going to hate this advice but, search for a correct size 8.75 - hell, put up a wanted ad on here.. and then join the E-Body forum and sell the one you have.
 
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Professor Fate, nailed it.

What you have is a truck rear. The 8 3/4 center section is commonly referred to as a 741 it is considered to be the weakest (not judging, just stating) as the pinion shaft diameter is the smallest of the 3 versions (741,742,489), also the new gear selection for the 741 is very limited, 742 more options, 489 even more options.

12" brakes are huge for an A Body, also are you measuring the ID of the drum for that measurement?

Good news is that a truck axle is a good narrowing candidate.
 
Demonic said:
It's about 5.1" wider at the flange dimension, so a little over 2.5" per side. You'd end up with heavily positive offset wheels looking gross, resembling a front wheel drive. A 66-70 B body rear housing is a much better fit at an 1.5" less, and a perch difference of only 1". Still requires welding in either case.

A nice Ridgid pipe cutter, a square and a welder are your friend.

Moparts on the Web - Main Index

Oh, by the way, welcome to the forum. Show us some pics of that V6 Dart, I know I'd like to see it.

:lol:
Click to expand...

In the “66-70” range you posted there are 2 different B body widths, ‘65-67 is narrower than ‘68-70. Your source of info is wrong.

Demonic said:
View attachment 1715565625

I believe the A dimension is the bare housing flange, with the backing plates removed.
Click to expand...

There it is, misinformation central. This chart is FULL of errors. It’s a terrible chart that has been pointed out as being wrong dozens and dozens of times. Please stop reposting this garbage.

The information you need is here

An accurate 8 3/4" rear axle width list

Professor Fate said:
Truck rear. Perches on top. 12" brakes. Find an A or B Body rear, much easier.
(V6??)
Click to expand...

Yeah, it’s a truck or van 8 3/4. An A100 8 3/4 is almost the same dimensions as an E body, might be one of those.

Either way, too wide to work in a Dart without shortening and moving the perches.

But a truck/van rear axle can be narrowed, if you send the axles out they can be shortened to whatever spec you like. Or DoctorDiff sells new axles for a pretty reasonable price. If you have access to a welder, or know someone that does, you can probably work with the axle you have and still spend a lot less money than buying an A-body 8 3/4, prices on those things are ridiculous.

And if the brakes are the 5x4.5” bolt pattern those are probably 11x2.5”
brakes, they outside diameter would be 12” but that’s not how they’re identified.
 
you need an A body width differential. Find one or pay the money to shorten the newly acquired E body one. Axle choice depends on horsepower. Doctor diff sells two axles complete with bearings already installed for around $300.
 
I realized the OP is talking about a 4 link anyway, so the whole deal with moving the perches is irrelevant.

Also, if you’ve got the skills to install a 4 link then you should be able to shorten that 8 3/4 too. I also wouldn’t worry about making it A-body width. Pick your wheels first and then make it whatever width you need to make them fit.
 
Thanks so much for replying you guys I really appreciate it. Well if I was to shorten it what are some good high performance axle shafts? Also what size would I need to get? thanks again heres pics also

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illrad91 said:
Hello guys I'm new to this forum and ok with my Mopar knowledge. Anyways I have a 1967 Dodge Dart original v6 and I wanted to change to GTS gerst 4link with the 8 3/4 E body I just bought. The 8 3/4 rear is complete with 3.23 and 12" drums but idk what id need to do to fit the rearend in My A Body dart. Also what kind of 8 3/4 is it? Looks original rear end with the 12" on them with lines and brake line also but idk. So please if you guys could help me I honestly don't want to shorten the 8 3/4 but if I have to what are the top of the line internal axles to get?

ThNKS a lot everyone and I hope to hear from you guys

View attachment 1715565598

View attachment 1715565599
Click to expand...

Why would you go to all the work of building a four link setup and then use a 8.75 rear end? If it is a drag car then put a Dana 60 in it. If it is a street car/road race car then use a Ford 9 inch. A four link install is going to require a ton of welding to the housing so the rearend needs to be stripped down anyway. At that point it only takes a little bit of work to cut the tubes to the proper length. Are you going to have a chassis shop install the four link or is this something you're going to tackle as a back yard project? You'll need a ton of tools, time and talent to do a four link conversion so narrowing the rearend will be the least of your worries.
 
AndyF said:
Why would you go to all the work of building a four link setup and then use a 8.75 rear end? If it is a drag car then put a Dana 60 in it. If it is a street car/road race car then use a Ford 9 inch. A four link install is going to require a ton of welding to the housing so the rearend needs to be stripped down anyway. At that point it only takes a little bit of work to cut the tubes to the proper length. Are you going to have a chassis shop install the four link or is this something you're going to tackle as a back yard project? You'll need a ton of tools, time and talent to do a four link conversion so narrowing the rearend will be the least of your worries.
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the rear end is bolt on. but Its mostly gonna be a street car but when time be I can easily hit the strip. I know I'm way over my head but its a good learning curve I appreciate the input didn't know it was that much work even if it just bolt on
 
Why not pick up a 8.8 rear end out Ford explorer, weld some perches on and go. Another plus is they have disk brakes on them.
 
illrad91 said:
the rear end is bolt on. but Its mostly gonna be a street car but when time be I can easily hit the strip. I know I'm way over my head but its a good learning curve I appreciate the input didn't know it was that much work even if it just bolt on
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The Gerst system is not a bolt in. Some parts bolt on but you have to weld the upper brackets to the housing. You'll also need a bunch of related fab work to make things fit properly. If you aren't an experienced chassis guy with a complete shop then you'll want to have a pro handle the install.
 
illrad91 said:
...but Its mostly gonna be a street car but when time be I can easily hit the strip.
Click to expand...
there's a lot of people here with fast dual purpose cars, running leaf springs. i don't know how long you've been wrenching on cars, or how old you are (there's no wrong answer), but the best way to get frustrated and dejected at building a car is to dive headfirst into a hole this deep without a lot of experience. make that car drive-able first. i don't mean around the block a few times and nothing too important fell off. make it so it's daily driver jump in with no worries reliable. as you do that, upgrade the stuff that needs replacing and learn the basics of how to take one of these apart and back together. look at everyone's build on here and see what you like. mostly, just enjoy the process.
also, don't throw anything away that isn't rusted rot from that car. 67's have some unique parts. someone will want them.
good luck :thumbsup:
 
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