727 to A518 swap

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kdbunn

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So I bought an A518 (2 pin) out of an early 90's van to swap into my '69 340 barracuda after I get it rebuilt. I bought a crossmember kit from USCT and understand I will need a different driveshaft. Is there anything else I need to be aware of structurally with this swap? Just throwing it out there....
 
If you install it with the tail lower than factory, then you will have to reset your pinion angle. So buy some shims. The lower tail will make your dip-stick read wrong too, and the oil may get up into the spinning parts, so I recommend a deeper pan, with a dropped pick-up, so you can safely drop the fluid level..
 
If you install it with the tail lower than factory, then you will have to reset your pinion angle. So buy some shims. The lower tail will make your dip-stick read wrong too, and the oil may get up into the spinning parts, so I recommend a deeper pan, with a dropped pick-up, so you can safely drop the fluid level..
Good to know, and totally makes sense.
 
Floor pan modification.
This is where I was going with my query. I read a couple of articles that indicated that the modified crossmember along with the 2nd Gen Barracuda's didn't require floor mods, but there are so many different examples of installs that i'm guessing some do.
 
This is where I was going with my query. I read a couple of articles that indicated that the modified crossmember along with the 2nd Gen Barracuda's didn't require floor mods, but there are so many different examples of installs that i'm guessing some do.
I've never seen one that didn't.
 
i Did this swap in a 68 dart. I didn’t modify the floor pan, but I did have to cut out the center of the torsion bar crossmember and weld in a piece of strap to tie it back together.

Lots of info on this swap on this site.
 
i Did this swap in a 68 dart. I didn’t modify the floor pan, but I did have to cut out the center of the torsion bar crossmember and weld in a piece of strap to tie it back together.

Lots of info on this swap on this site.
Did you use the modified dropped Trans crossmember made for this swap?
 
This is a really great swap, so don't let a lil thing like lack of it being a bolt-in, deter you. That .69overdrive lets you run just about any rear gear up to about 4.56s in a streeter.
as you probably know 4.56s x .69=3.15 final drive, and AFAIK all 518s have a loc-up.
With the starter gear of 4.56 x 2.45=11.17, you don't usually need a stall.
Typically tho, on the street, the A518 is run with 3.91s, for a lil longer 9.58 first gear. However this brings the Final Drive down to 2.70, and so 65= about 2185 by the math.
If you are installing this for fuel economy AND installing a longer period cam, you may not be able to give the engine enough ignition advance with the factory-style distributor, to get the fuel economy increase that you might be expecting. To cruise at 2185rpm, the engine has to making strong torque, so that it doesn't need a lot of timing advance.
I got that torque with 11.3/1 Scr, and a [email protected] cam*. But with the pressure pushing 190 or more psi, I went with Alloy heads to not get into detonation under power. At that time I was cruising at 65=1600 with a manual trans. It got phenomenal gas-mileage.
 
This is a really great swap, so don't let a lil thing like lack of it being a bolt-in, deter you. That .69overdrive lets you run just about any rear gear up to about 4.56s in a streeter.
as you probably know 4.56s x .69=3.15 final drive, and AFAIK all 518s have a loc-up.
With the starter gear of 4.56 x 2.45=11.17, you don't usually need a stall.
Typically tho, on the street, the A518 is run with 3.91s, for a lil longer 9.58 first gear. However this brings the Final Drive down to 2.70, and so 65= about 2185 by the math.
If you are installing this for fuel economy AND installing a longer period cam, you may not be able to give the engine enough ignition advance with the factory-style distributor, to get the fuel economy increase that you might be expecting. To cruise at 2185rpm, the engine has to making strong torque, so that it doesn't need a lot of timing advance.
I got that torque with 11.3/1 Scr, and a [email protected] cam*. But with the pressure pushing 190 or more psi, I went with Alloy heads to not get into detonation under power. At that time I was cruising at 65=1600 with a manual trans. It got phenomenal gas-mileage.
Cool. I am definitely going with the swap- I just wanted to get an idea of what other body mods I might encounter as most of the threads talk about wiring and mechanical aspects. I am going to go with a stroker kit from Hughes and am running 3.73's (I think) right now. The article I read about lock up vs. non lock up said that the '90 to '93 46RH's with a 2 pin connector (which is what I have) are non lockup style transmissions and can be run with the stock 727 torque converter. Maybe that is incorrect. You get so many different stories it's hard to know what is correct and what isn't.
 
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