727 swap to A518 is done with pics and a vid

[Paul G]

Finished the install today. I had a local shop in Surprise, AZ, All About Auto, John Sholtz, do the heavy work for me. He overhauled the A518 core I picked up on Craigslist. It has a 3 wire plug on the tranny, 2 wire tranny's dont have lock up, watch for that. We used a Hughes 11" lock up converter. He did the swap, and then back at home I wired in the automatic overdrive and lock up converter myself. I used pressure switches and the three pin plug from PATC, the switches plumbed in to the pressure port on the passenger side of the tranny. Picked up a B&M throttle position switch, and a generic relay from Summit Racing. Picked up an angle bracket from Ace Hardware to mount the switch. It mounted under the Bouchilon kick down cable bracket perfectly and connects to the throttle linkage. Works well. Relay is mounted to the firewall behind the Distributer (small block).  

Basically we had to widen the trans tunnel a little bit to accommodate the wider body of the A518. Just hammered out the sides a little. Not really noticeable inside the car.

Mounted the pressure switches to the tranny before it went up.

Cut the old mount off the cross member and welded in a new plate to hold the tranny, used a cheap tranny mount for a Chevy pickup. It was an easier fit to modify the cross member for the Chevy mount. And the mount bolted right up the bottom of the A518.

Linkage went in with no problems, it is a column shifter, and the Bouchillon kick down cable makes it very simple.

Shortened the drive shaft about 3 ½".

Wired it all in and it works very well.

Pressure switches from PATC mounted to the trans.


The 3 pin plug from PATC plugged in.


Floor hammered out a little. I could go back to the inside and move the floor back out a little. We went just a bit too far I think.


Modified cross member with the Chevy truck trans mount.



Throttle linkage with the throttle position switch mouted under the Bouchillon bracket. You can barely see the relay on the firewall.


All fineshed and ready for the test drive.


The test drive. Click on the picture and it will start.

[Paul G]

I got some pictures of this 1971 GTX that was in Johns shop. It has a 500" big block, A518 with an ultra bell, paddle shifters, full custom car, high dollar. And, no A/C, in Phoenix! What were they thinking? John has had it for a while ironing out some issues it had. I offered to take it home and do some work on it for him. 

[64dartgt]

Sweet!  I thought about doing an overdrive unit when my 904 went but the aftermarket kits were way too expensive and  what little I could find about the A518 swap made it sound a lot tougher than it apparently went for you.  The pressure switches are a great idea that needs a little refinement.  Perhaps you can make use of the current switch and include an adjustable electronic timer or something to allow you to fine tune a delay into the circuit.  Just thinking off the top of my head here and not an electrician!

http://www.grainger.com/Grainger/SQUARE-D-Time-Delay-Relay-2DZ01?Pid=search

Regarding the 1st to 2nd issue...perhaps a shift kit would help.

Could you Please post where you sourced the truck tranny mount and exactly what it is.  It looks like it fit great.  If my 904 doesn't stand up to my new 340 this is definitely the way I want to go.  I'd appreciate a few more photos of the tranny mount.  Is it just bolted in on each side?  Did the A518 bell housing match right up?  The mount looks like it was cut and then an pieced of channel fitted to it to adapt to the tranny.  Any additional details would be greatly appreciated.  I can't believe that you were ticking over at about 2000 rpm at 70mph!

[flyinlow]

Nice Job Paul.   

Not that I won't always have fond memory's of the TF 727, but after 12,000 miles with the A518 , I can't imagine going back for a street car.

[tan top]

good stuff    , think i seen that roadrunner in a mopar mag a few years back 

[Paul G]

Could you Please post where you sourced the truck tranny mount and exactly what it is.  It looks like it fit great.  If my 904 doesn't stand up to my new 340 this is definitely the way I want to go.  I'd appreciate a few more photos of the tranny mount.  Is it just bolted in on each side?  Did the A518 bell housing match right up?  The mount looks like it was cut and then an pieced of channel fitted to it to adapt to the tranny.  Any additional details would be greatly appreciated.  I can't believe that you were ticking over at about 2000 rpm at 70mph!

The trans mount we used came from O'reilys, part #ANR 2268. It matched the bolt pattern on the trans. Just cut the factory mount off the cross member and welded in a plate to hold the chevy mount.

The A518 uses the standard small block bell housing bolt pattern. Bolted up to the engine with no issues.

We went on a 90 mile trip last Sunday. Half was highway, the other half city driving. The tank was full when we left. Got home with just under 3/4 left. That trip used to use 1/2 the tank. Mileage is better, I can tell how much better next fill up. Used to get around 10 to 12 MPG, 9 when the rear tires are the only ones turning.  Cruises at 70 around 2300 rpm.

[64dartgt]

Thanks for the extra photo!  By the way...what are you running for a rear gear ratio? 

[Paul G]

3.91 gears.

[Paul G]

I have been doing some tweeking to the controls for the A518. I didn't like where the OD and LU were coming in at with the line pressure switches I got from PATC. The number on the switch is supposed to be the approximate MPH it switches at. Maybe with a street friendly or cruise gear it would be, with my 3.91 gears it was way off. Found an adjustable pressure switch from Stewart Warner that works well. Part #SWP11489. Got it on Ebay from D&D Instruments for $36.00. Picked up an Agastat timing relay part #VTM1QCD also on Ebay for $9.94. The timer needs a resistor mounted to it to set the required time delay. Very simple to do. I wanted a 500K resistor for about a 5 second delay, Radio Shack had a 470K, close enough. Still need to mount the timer some where safe.

This is a vid of how the car shifts now. Click on it and it will open.

[flyinlow]

Interesting,is the govenor preasure not about 1 psi per mph?

[Paul G]

Interesting,is the govenor preasure not about 1 psi per mph?

Cant really say? I had the A518 rebuilt before it was installed. Shifts well, down shifts well. With the switches I had from PATC the actual switching points were about 5 mph over the number on the switch.

From PATC;

  NOTE: The way governor pressure works is 1 pound of pressure per square inch equals 1 mile per hour unless someone has changed the tire size, or rear end ratio, or governor springs and weights. The vacuum switch acts as a throttle position sensor and the oil pressure switch acts as a speed sensor.

In my application tire size and gear ratio have changed, that is why I think the PATC switches arent acurate.

[200MPH]

looks great

[red79]

Beautiful job. I have been mulling over attempting the same swap in my 72, would love to have the OD gear without sacrificing much of the ruggedness of my 727 (GV too much $$$).

My only concern is the shifter linkage. I have a slap stick console which I love, but all the 518 swaps I've seen in 3rd gens are either column shift or use an aftermarket cable shifter. Is there enough similarity in gear selector location on the tranny between the 727 and 518 that I'll be able to keep my slap stick? Or will I have to sacrifice it to the overdrive/lockup gods?

[Paul G]

Beautiful job. I have been mulling over attempting the same swap in my 72, would love to have the OD gear without sacrificing much of the ruggedness of my 727 (GV too much $$$).

My only concern is the shifter linkage. I have a slap stick console which I love, but all the 518 swaps I've seen in 3rd gens are either column shift or use an aftermarket cable shifter. Is there enough similarity in gear selector location on the tranny between the 727 and 518 that I'll be able to keep my slap stick? Or will I have to sacrifice it to the overdrive/lockup gods?

Shift linkage location on the A518 is the same as the 727. Only problem is getting the trans high enough in the tunnel. It is all the way up tight to the top of the tunnel. Had to hammer out the sides of the tunnel to make room.

[red79]

Good to know, would love to put some more cruising miles on the interstate without winding up to 3k rpm all the time. If I ever get the chance, hope it comes out half as pretty as yours! 

[rcannon440]

Did you happen to take any photos of the transmission bracket while you were making it? I feel comfortable with most everything except the rear mount. I just bought a 518 to put on my 440. I'm going the route of the Ultra bell. Your transmission looks good did you paint it?

[rcannon440]

What mount was used on the GTX?

[Paul G]

Did you happen to take any photos of the transmission bracket while you were making it? I feel comfortable with most everything except the rear mount. I just bought a 518 to put on my 440. I'm going the route of the Ultra bell. Your transmission looks good did you paint it?

No pics of making the mount. It was actually a leftover from some other project that worked well on this one. The trans was painted with some gloss gray paint is all. The GTX is using the stock mount just cut off the cross member and a box welded back in the new location to mount it back up to the xmember. Good luck with your install and start a thread when you do it. We love to see it.

[flyinlow]

Paul, did the GTX have Schumaker tri Y headers?

[Paul G]

Paul, did the GTX have Schumaker tri Y headers?

I dont know for sure? I have one pic where the right side header collector can be seen, it looks like only two tubes go in to it.

[rcannon440]

I just finished performing this swap in my 69 Charger and I have a bad pulsating vibration. It's not drivable the way it is, do you think I might have a problem with the pinion angle? I checked it and it seems OK. Did you have any pinion angle issues? 

[ACUDANUT]

Where is the Video ?

[Cooter]

I just finished performing this swap in my 69 Charger and I have a bad pulsating vibration. It's not drivable the way it is, do you think I might have a problem with the pinion angle? I checked it and it seems OK. Did you have any pinion angle issues?  

This tends to be a problem with the OD trans swaps.   Driveline angles (Without hacking your car's Crossmember to where the tailshaft sits inside your console), and
Did you have the driveshaft balanced? Is it a new one that came pre-balanced? MY own $400.00 5-speed conversion vibrates as well, but I'm running an older driveshaft too that I'm all but Sure isn't balanced for the RPM's it is turning at 70 MPH.

[Paul G]

It is critical to have the trans located about 1 1/2" off center to the passenger side. And it has to be high enough to get the pinion angle correct. The pinion angle has to be correct side to side as well as up and down.

[flyinlow]

I just finished performing this swap in my 69 Charger and I have a bad pulsating vibration. It's not drivable the way it is, do you think I might have a problem with the pinion angle? I checked it and it seems OK. Did you have any pinion angle issues? 

What converter did you use and what engine do you have ? Most stock 518 converters are for externally balanced engines, might cause problems with a steel crank big block? Just a thought.