Part 1: Is an A-518 swap for you?And the Roach Runner?

The A-518 (bottom) seems huge in this photo ascompared to the 727. Much of the effect is mere-

ly perspective. Besides the obvious differencesin the tail section, you may also notice the elec-trical plug on the A-518 (arrow) to hook up the

overdrive and lockup wiring harness and thelarger cooling line ports.

BY THOMAS A. DeMAUROP h o t o s b y t h e a u t h o r a n d J e r r y S l a t t e r y

D i a g r a m s c o u r t e s y o f C h r y s l e r C o r p . a n dJ V X P e r f o r m a n c e T r a n s m i s s i o n s

W

Note the differences in the A-518 3-hole triangular mount setup(top) as opposed to the 727 two-hole layout. Also, this A-518 tailhousing is from a '96-and-up model as the electrical connector forthe magnetic speedo pickup is visible.

[hen it comes to our Mopars, we want it all. Ours hasto be the cleanest, the fastest and the hottest, barnone. We also want them to do everything well and

eliminate all compromises, which we know to be impossible,yet we are not deterred.

Such is true for the Roach Runner, which I want to becompetitive in every way. One area that is a classic com-promise is rear gear ratio. More times than not, a steepgear is needed to extract the most that the engine has tooffer for quarter-mile performance at the expense of cruiserpm and top speed. We are not building a Bonneville car, sotop speed is not too much of a concern, but cruise rpm cer-tainly is since the Roach will see lots of highway miles. Youmay recall that the Roach's 83/4 Sure-Grip rear was rebuiltand a 4.10 rear gear was installed with quarter-mile ETs inmind. For this reason, we decided to investigate an over-drive trans retrofit for the project.

The extra girth of the A-518 transmission's overdrive unit and tailhousing are readily apparent when compared side by side withthe 727 tail housing. The driveshaft yolk will remain the same,however, since both output shafts have 30 splines. HIGH PERFORMANCE MOPAR 33

If cost is not a major concern, abrand-new A-518 con be had fromthe MP catalog under part No.P5249 ] 66 for approximately$1,575 list and $1,375 out thedoor. You will, however, have toforego the lockup feature, as thisassembly is available in non-lockuponly. If you are running a small-block and you want a new A-500,it, along with the lockup feature andneeded wiring harness, can beordered from MP (part No.P5249165] for fhe same price asthe A-518.

If you plan to have a used A-51 8rebuilt by a tranny shop, you can askthem to find a core for you for aprice. But if you are a do-it-yourselferand you like to shop the used partsads and junkyards, then you'll need

to locate a 1990-presenf Dodge Rampickup, van or V8 Jeep to score yourA-51 8. Below are the Hollander inter-change numbers for the Dodge pick-up and van through 1996.

Hollander Interchange Numbers ForThe Dodge Truck

Here is the A-518 from the passenger's side.The upside down "V" is a quick way to spot anA-518 in a pile of transmissions at the localbone yard.

The A-518 is 727-TorqueFlite based,giving it more torque capacity than theA-500, which borrows its design fromthe 904 TorqueFlite. So we chose the A-518 for durability reasons.

Due to differences in the bell-housing bolt pattern fit's a small-block), this swap is not a drop-it-in-and-go situation when a big-block is involved. Even though itis not low-buck, the long-term

Most frequently asked swap questions

Lock-up converter durabilityand performance

In case you have thoughts of just swapping the 727 tail shaft for the A-518OD and tail shaft, here is why it won't work. There are just too many differ-ences to overcome in the mounting area.

payoff is having the best of both worlds when it comes toacceleration and cruiseing while bringing your vintageMopar up to modern-day standards in the transmissiondepartment. So even if this swap is beyond your currentbudget, and we will tell you how much it costs, there is stillgood information to be had, as some of the upgraded com-

The eight-digit "PK" number can be found on the driver's side pan rail.Next to it is a four-digit production date based on the 10,000-day Juliancalendar followed by a four-digit serial number. Many of the PK numbersare listed in the "A-518 Running Upgrades" section of Part 2 so thechanges can be applied to the specific numbers. A complete listing of allof the PK numbers from 1990 to 1998 is too extensive to post here, butthe dealers have them in the parts books.

This lockup converter is from a diesel application. Notethe lack of the starter ring gear normally found onMopar converters.

IMPELLERFRONTCOVER

THRUST WASHERASSEMBLY

IMPELLER

PISTON TURBINE STATORHere are the internal components of a lockup converter.

The 1¼-inch-deep 727 pan (left) vs. the 2½-inch-deep'90-95 A-518 pan. The'96 and-later panhas a small bump on the bottom lo clear the extra electronics.

ponents found in the '90's 5 I 8 can be retrofitted into a vintage 727.For part 1 of this series, we will touch upon what is involved in doing this

swap. We will also tell you where and how to find an A-518, which units shouldbe avoided, and what the advantages of an overdrive swap will be.

In subsequent issues, we will discuss running changes made to the A-51 8 overthe years, detail the modifications made to our 518, by Level 10 Transmissions, forincreased performance and durability and then get into the nuts and bolts of the

How do you tellthe lockup A-518from the non-lockupA-518?

The differences between the lockup andnon-lockup input shaft can be seen here.The lockup piece on the top has an exten-sion ahead of the splines (with a sealingring) to engage the lockup clutch. Thelockup uses a 23 spline shaft and thenon lockup uses a 24 spline shaft.

Also, lockup A-518S use a 3-pin case con-nector, while the non-lockup uses only a2-pin connector in Dodge truck applica-tions. The Jeep needs an 8-pin case con-nector, as seen here because it has elec-tronic shifting.

swap, including mods needed to fit the tranny into the Roachand how to set up the linkage, the OD and the lockup feature.

For the most part, we are dealing with an A-518 swaponly. The A-500 is periodically mentioned because it is an

Case dimension diagram.

alternative for small-block swaps and because some partsare interchangeable with the 518, such as the overdrive unit.However, space does not permit a full dissertation on the A-500 as well, so we'll have to save that for another article.

Special thanks to product engi-neer Neil Laymon of Chrysler'sKokomo transmission plant for hishelp in researching this article.

SourcesLevel 10 Installation Center

188 Route 94 NorthHamburg. NJ 07419

973-827-1000

The JVX adapter kit makes this swappossible. Shown here are kits for V8gas engine A-518s and the V10/dieselA-518 and A-618 transmissions.

Level 10 Showroom32 Route 46

Lodi, NJ 07644973-546-8200

JVX Performance Transmissions1458 Chelsea Ave.

Memphis, TN 38108-1103Order, 800-727-5891Tech, 901-274-7238