318 poly to 383 swap

[Robbie]

Hey guys and gals, I am getting ideas together for an engine swap I may be doing in the future. The subject is my Great Uncle's old (I think '65') CSS that has seen better days. It is going to need a lot of work to say the least. It also hasn't been running or on the road in decades. Besides the endless sheet metal work needed to be done, I am toying with the idea of replacing the original 318 poly with a mildly built 383 that my dad is pulling out of a '71' Challenger (he's replacing it with a 440 from a '77' 3/4 ton 4wd truck). I haven't gotten into the components on hand, but would I be able to use the 727 from the 4wd truck behind the 383? I think the 4wd trans is physically shorter and may need a different tail shaft housing. If I was to scrap this idea, will the automatic shift linkage mounted on the dash hook up to a later model 727? I'm usually a proponent of keeping everything original especially since it is an original CSS, but the older I get and since the truck needs enough work that a sane person would just scrap it, I think that when I finally get into it, I'm going to do what I want and make it fun to drive. I'm also looking at installing a Crown Vic. front suspension and lowering it. Also possibly adding a used Gear Vendors overdrive which may work with the short 4wd 727 for overall length. After all, I'll need something to haul my '74' Eliminator drag boat project right? This project is still in the idea stage, so I won't be turning a wrench on this for some time. Thanks for any help.

[Duh]

Hola Sir

The Engine Cooling Fan - The Starter Motor - Alternator - The Torque Convertor and The Coil of the A-318 are the same
items used with a 383.

The size and fitment of the A-318 Small Block ( SB ) Bell Housing will never go to any 383.

In order to make the 383 fit into your truck you will need a Oil Pan with The Slump in the same place as your A-318's and
a set of "Center dumping" Exhaust Manifolds.

To make "it go" --- you will need a Big Block ( BB ) Automatic Transmission to bolt to the 383.

A set of BB Truck Motor Mounts will need to be used with The 383.

The Transmission Shift Linkage is just a swap of The Transmission's.

--------------------
Your Dad will need The Oil Pan/ Oil Pick Up and The Exhaust Manifolds from The "car" 383 to bolt to The "truck" 440.

Also let you Dad know the 383 is lighter - Rev's Quicker - Rev's Higher and uses Less Fuel that any 440.

-----------------------------------------
Get you truck operating first and then venture into lowering it and etc.






Rodger & Gabby
FltSgt@outlook.com
COS

[Hobcobble]

Robbie,
Is the truck an original manual or auto tranny?
John

[Robbie]

The CSS is an auto with the dash shifter, the '77' 4wd is an auto column shift. I keep telling my dad that the 383 would be better in the Challenger, but he is adamant about having the 440 in it. He always wanted a '70' RT Challenger like in Vanishing Point (who didn't). It's a '71' 318 car that had the 383 put in it. He has the '70' grille assembly and tail panel to swap for it. It has been on the waiting list for about 10yrs. I think I have him convinced to keep it a '71' but not keep the non-original 383 in it. Do you guys think I would be able to use the 4wd 727 auto in the CSS? I'll probably need to have a new driveshaft made up for a regular 727 with the crown vic front suspension anyway. Thanks.

[Robbie]

Well, I've been absent for some time, sorry about that. Needless to say, I've been getting motivated to get rid of some projects, finish some and start/re-start others. The CSS needs attention, and I'm getting motivated to excavate it from its resting spot and start making something happen. This will be a long slow process, but I'll try to update the progress as it happens. I'm not sure what direction I want to go with the drivetrain so I'll just start with getting it to a spot where I can get an idea of how much needs to be done or can be saved. I'm looking forward to picking away at it and any suggestions anyone can give along the way. Thanks in advance.

[PwrWgnDrvr]

Its been 7 yrs since your last post and you and the truck are that much closer to the grave. From the 7 yr old pic, looks like the truck is going to get there first.

[Conductorblg]

A few random thoughts to add from my personal experience for the original poster or anyone else contemplating this or a similar swap;

The original 383 swepty pickup exhaust manifolds are smaller internally than the later pickup 440 manifolds, but the later manifolds match up to the heads and the outlets are the same 2" diameter. The original 383 pickup passenger side manifold is not a center dump and actually dumps out like standard passenger car manifolds between the #5 and #7 ports. This should only be a concern if you were to use an original pickup single exhaust Y pipe. Plenty of room to use the later center dumps on both sides with headpipes that drop straight down and back. Bear in mind that the outlets are not perpendicular to the ground, but angle slightly inboard. Also, the later center dump manifolds have long necks that tend to crack from the weight of the exhaust pipes. To reduce that possibility, brackets to carry the exhaust pipe weight could be mounted to the bell housing not unlike the stock bracket used to carry the weight of the single exhaust Y pipe.

Something else to consider is the factory axle ratio in the 3/4 ton pickup with 383 and 727 is a 3.54, something in the 4.10 range appears to be common with a small block.

Original B block 727 transmission on my 68 appears to be the same externally as those used in passenger cars, it uses the stock extension shaft housing rear mount on an additional bolt in crossmember. Without the mounts on the bell housing to tie the front leaf spring rear eye mounts together to keep them from twisting, the factory utilized a bolt in channel crossmember in that same spot that crosses under the transmission pan. A one piece driveline with a slip yoke at the transmission was used. If the earlier truck uses a two piece driveline and carrier bearing and/or bell housing mounts, adapting the driveline to a transmission with a shorter extension housing intended for four wheel drive might save a lot of grief even if it included eliminating a driveline mounted parking brake and utilizing the rear axle parking brake setup like the later models. Using a Gear Venders OD would likely mean using a rear axle with parking brakes also.

There should be a boss on a stock 727 transmission case to mount the stock cable shifter transmission bracket. I used an Ultra Bell to adapt a RH47 (diesel) overdrive to my truck. If your truck is a small block with a 727 that does not use bell housing mounts, using one of these bell housings would enable the use of the A motor original transmission. These bell housings do require an 11" torque converter and this in turn required me to use the smaller, although stock flexplate. Bear in mind this bell housing has no shift linkage boss because it's a racing piece intended to replace the stock 727 bell housing. This required a bracket to be built to mount the cable bracket at the transmission end for the dash mounted shifter. I might still have the paper template laying around that I made up to make this bracket.

The small block TV (throttle valve) linkage can likely be adapted to the B block. On my truck, the stock TV linkage for the 383 required some minor adaptation to change from the original 2 barrel carburetor and manifold to an aluminum hi rise and four barrel anyway. The later replacement of the 727 with the 47RH only required tightening up the linkage adjustment 5 turns to get stock shift points.

As an aside, due to the added cost of going through a grenaded OD unit, using the best rebuild components, adding a shift kit, aftermarket servo, additional frictions and steels to the clutch packs, and paying someone else to do it, my transmission rebuild cost was similar (3000.00) to the cost of a Gear Venders unit. Automatic operation of the stock OD transmission with aftermarket pressure switches in place of a stock computer is totally seamless. Spending a little extra for adjustable switches allows me to set OD and lockup engagement to suit the vehicle and my driving style. With OD and lockup engaged, truck now runs down the freeway doing 70 MPH @ 1800 RPM, before it would be taching 2600 RPMs @ 65 MPH. By using a separate toggle switch in each ground circuit for the OD and lockup solenoids (as opposed to an on-off switch in the supply circuit), I am able to individually engage lockup and OD. Admittedly, the added beef (and rebuild cost) of the diesel 47RH over a 46RH (gas) one for a not raced or even remotely pushed hard everyday driver pickup is overkill, but total adaptation cost of the 47RH was probably less than that needed to rebuild the 727 and add a Gear Venders unit.

[Robbie]

Thanks for the info, and right you are sir, I'm not getting any younger.

[jeffc57]

66 AND UP 727 USED a different shifter than the 65, 2 cable vs. single cable for the parking sprag, the 66,67,68 dash sifter use with any 66 up 727
and are compatible with later 727

[Conductorblg]

I had forgotten the 65 used the two cable setup from the previous year's pushbuttons.

Now that the original poster is unsure of the direction he wants to go with the drivetrain, perhaps the easiest way to update the CSS is to find a running and driving 91-2-3 doner with a Magnum 360 (5.9) or 318 (5.2) or 12 valve Cummins (5.9) motor and adapt the Sweptline nose and cab to the later chassis. Sweptline rear fenders from a late 65 to 71 could even be grafted onto the later box. Pick the right truck and this would give you integral power steering, power disc brakes, independent front suspension (or the factory Ram Trac system if 4wd), electronic ignition and fuel injection (with the Magnum motor), automatic overdrive transmission, large inboard fuel tank, and load sensing brake proportioning. The Sweptline instrument panel wiring should be a fairly simple meld into the later wiring harness. I think if I found a doner with AC, I would graft it in too.

[Conductorblg]

Forgot to add, lockup converter was offered with gas motors in the pickups, 91 and later, but wasn't available behind the Cummins diesel until the 93 model year.

[dougdodgeman]

lockup convertors didn't start until '94 model year, actually. Doug

[Conductorblg]

I asked a friend of mine yesterday (he has had many Sweptlines over the years and still has a 62, 64, 66, 68 motorhome, and a 70) and he confirmed that a 65 with a 727 would use a rear mount on an additional bolt in crossmember with a separate bolt crossmember connecting the frame together in place of bell housing motor mounts like my 68. He also confirmed that the 65 shifter and transmission are one year only pieces and as another poster stated in this thread, not compatible with other years, pre or post 65. He did say he thinks a 66-68 dash mounted shifter ("A" pickup/van unit, also found some or all motorhomes of that vintage is a different piece) should bolt in place of the 65 unit without modifying the dash.

Being that the CSS was an unusual and interesting option for only 2 years on these trucks, even without the rarity of the 426 motor, it will be interesting to see if the original poster actually saves his, and if he does, what direction he takes it.

[PwrWgnDrvr]

The CSS pkg ran from 64-67, NOT just 2 yrs. It was a trim pkg and had nothing to do with drive train or engine.
The HPP pkg was the truck with the 426, and it ran from 63-67.
You can get the facts and history here:
http://www.cssregistry.com/