3.6 in A-body

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Hi Everyone, I'm in the early planning stages to put the 3.6L in my '64 Dart Conv. As I see (what I believe to be) the outrageous prices for an 8 3/4" and now even the 8 1/4", I'm wondering if a better option may be to retro-fit the rear end of from a Challenger/Charger, so as to bring the entire drive train over from a donor junkyard car. i understand that's going to require a decent amount of modification, but hey, a friend put a jaguar rear suspension in a '31 Chevy roadster, so it's certainly doable. Thoughts?
 
I'm just starting my research, and am seeing 8 3/4" at $2k-$3500 all day long - which makes me long for the '80's when the junkyards were full of them! The few 8 1/4" I've seen were pushing $1k as well. My Dad always said 'asking ain't getting', so I don't know what they're actually selling for. I'm looking at options right now.
 
OH! Your looking at complete ready to drop in rear ends.
Yes, they get pricey. Look around for a used unit that should come in around half of that price. I don’t know what your particular do it yourself skill level is, but, if you don’t mind getting a bit greasy, now is the time to learn.

There is also a possible option of narrowing a Dakota or RAM rear end. While I don’t know the cost since prices vary shop to shop region to region, it is a possible route.

Once obtained, new axles to suite the shortened tubes is all it would be. If your not going to harp on it, used OE small bolt pattern axles are inexpensive. I have 2 sets collecting dust now. (I’m not sure if there is an A body set. 1 I have is a B body set.)

Keep hunting the classified section.
 
@Gina Grahame there is a popular swap that will work great for your car. A Ford 8.8 out of an explorer with one side narrowed to center the diff. You get disk brakes, strong parts, (31 spline axles), limited slip diff and good gear ratios. 3:73-4:10. Lots of people using them in A bodies. Do a search here for 8.8 Ford diff and start reading. Best part is they’re cheap. Junkyard prices with race car level of parts. Oh and start a thread on your build so we can follow along.
 
@Gina Grahame there is a popular swap that will work great for your car. A Ford 8.8 out of an explorer with one side narrowed to center the diff. You get disk brakes, strong parts, (31 spline axles), limited slip diff and good gear ratios. 3:73-4:10. Lots of people using them in A bodies. Do a search here for 8.8 Ford diff and start reading. Best part is they’re cheap. Junkyard prices with race car level of parts. Oh and start a thread on your build so we can follow along.
Thank you! I'll look into it :-D
 
Hi Everyone, I'm in the early planning stages to put the 3.6L in my '64 Dart Conv. As I see (what I believe to be) the outrageous prices for an 8 3/4" and now even the 8 1/4", I'm wondering if a better option may be to retro-fit the rear end of from a Challenger/Charger, so as to bring the entire drive train over from a donor junkyard car. i understand that's going to require a decent amount of modification, but hey, a friend put a jaguar rear suspension in a '31 Chevy roadster, so it's certainly doable. Thoughts?
if you're into fabricating, why not adapt the long arm coil spring front suspension w/the rack & pinion stg. You'll get the disk brakes, and the handling & steering of the late models. I love the handling and road feel of my 09 Charger PP.
 
if you're into fabricating, why not adapt the long arm coil spring front suspension w/the rack & pinion stg. You'll get the disk brakes, and the handling & steering of the late models. I love the handling and road feel of my 09 Charger PP.
That's certainly an option. I upgraded the torsion bars to 340 bars, brakes to disc, and swapped out the manual steering box to new, tighter, one. (3 1/2 turns vs the stock, 4 1/2 turns I believe)
 
the real issue with putting a 3.6l in a more narrow 66 is the exhaust

I struggled with it in my wider 1972. I would be concerned its even possible on a early A-body.

The center exhaust ports dump exactly in the narrowest part of the chassis. The Inner fender blocks it on the right.


Passenger.jpg


The steering coupler is even closer on the Left. Forget about power steering unless its a rack & pinion.
Drivers Side (1).jpg

20190629_190712.jpg
 
the real issue with putting a 3.6l in a more narrow 66 is the exhaust

I struggled with it in my wider 1972. I would be concerned its even possible on a early A-body.

The center exhaust ports dump exactly in the narrowest part of the chassis. The Inner fender blocks it on the right.


View attachment 1715677416

The steering coupler is even closer on the Left. Forget about power steering unless its a rack & pinion.
View attachment 1715677415
View attachment 1715677418
Really interesting, thanks! I thought the 3.6L would provide much more room than either the 3G Hemi or old school small block. I see I have more research to do :)
 
I’m not sure about the HEMI, but the old school LA is an easy thing to swap in once you have the engine mounts.
AEC314C1-95B4-45D5-B378-AA3FF44349E1.jpeg
 
Really interesting, thanks! I thought the 3.6L would provide much more room than either the 3G Hemi or old school small block. I see I have more research to do :)

I thought so too. Its a 60 degree v6. it should be more "narrow" than a 90 degree V8.

Nope, the 3.6L is WIDE. Its DOHC ,which allows it to flow more than the best CNC race head (299cfm at just .400" lift), also makes it a pita to swap. Valve cover the valve cover(max width), its as wide as a 440. Combine that with its unfortunate exhaust placement which just so happens to be EXACTLY at narrowest part of an A-body's engine bay, it was a challenge getting the exhaust out.

20200619_155143.jpg
 
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Never mind I found what it looks like.
E73F0797-0D93-4FD6-A06C-0144054BA97A.png

It is very similar to a Honda j35-37 v6 integral exhaust outlet.
D337F2EE-40F9-44E4-B80B-376D44A0738F.png

I bet with some creative work you could use the Honda factory headpipe and it is a nice flowing, very tight radius 90 bend. And it has an 02 bung right up top. They are plentiful at the junkyards.
AD3EEF08-B5F5-4F26-A0C7-1C5385737128.png

Just a thought.
 
I thought so too. Its a 60 degree v6. it should be more "narrow" than a 90 degree V8.

Nope, the 3.6L is WIDE. Its DOHC ,which allows it to flow more than the best CNC race head (299cfm at just .400" lift), also makes it a pita to swap. Valve cover the valve cover(max width), its as wide as a 440. Combine that with its unfortunate exhaust placement which just so happens to be EXACTLY at narrowest part of an A-body's engine bay, it was a challenge getting the exhaust out.

View attachment 1715678281
<<..wide as 440..>>
Holy moly!.. This is making me reconsider a 5.7 3rd Gen Hemi, as it seems so many aftermarket parts are available for the swap.
 
<<..wide as 440..>>
Holy moly!.. This is making me reconsider a 5.7 3rd Gen Hemi, as it seems so many aftermarket parts are available for the swap.
You will have a much easier time installing something that has become popular in the aftermarket and it will require much less one off fabrication. But what’s the fun in that?
:lol:
 
Just a bit more because I gets done quicker...
Even better if your fab skills are lacking.
I’m just glad places like Holley have a good amount of stuff for the G3 swap!
 
You will have a much easier time installing something that has become popular in the aftermarket and it will require much less one off fabrication. But what’s the fun in that?
:lol:
haha!! that is true. Unfortunately, I will have to hire out most of the work (I live in an apartment and can't do it on premises), so easier translates to less expensive at this time :)
 
A mild 360 with exhaust manifolds fits relatively easy in an early A and makes for a very nice driver. Add an overdrive and some 3.91 gears with a decent converter and you’ll have a car you won’t get tired of any time soon.
 
A mild 360 with exhaust manifolds fits relatively easy in an early A and makes for a very nice driver. Add an overdrive and some 3.91 gears with a decent converter and you’ll have a car you won’t get tired of any time soon.
A mild small block (318/360) was my thoughts until the 3G hemi came out (what Mopar lover doesn't get excited at the prospect of owning a HEMI??!) . The overdrive would need to be essential for a daily driver; do you have suggestions for the donor trans?
 
If I was building an early a I would not go the gen 3 hemi route. It’s a great engine and can be bad *** but it sounds like with your current situation fab work needs to be paid for, and a hemi swap needs a bunch of fab, =$$$
I would do a traditional small block and for ease of install look at a 200-4r gm overdrive. They can be built to handle any power level, You can adapt them to a small block, and they are much smaller than a 46re. So floor mods are kept small, although maybe some hammering is necessary. I used a 46re behind my magnum and it’s a good trans but requires the ecu to run it. The 46rh can be used with some Hobbs switches and control is hydraulic, and they’re nice but still huge in comparison. So my early A would be a 9.5:1comp 360-2004r with exhaust manifolds and 2800-3000 converter with steep gears. That would be a fun car and you could drive it anywhere. If I got tired of it I’d add boost. But that’s just me. Happy hot rodding.
 
I believe @ocdart has used that trans and a few other members as well. Hopefully he’ll chime in.
 
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