318->383 swap

Kahn

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A guy near me is selling a 383 w/ 727 tranny out of his 67 fury 3. He says that it’ll fit into my 67 fury 2 that has the 318 in it. Is this true? Do I need a k frame? I’m not sure if someone is just trying to make a couple bucks off me or is actually correct. All help and info appreciated. Thank you!
 
Our cars do not have K frames. The front stub is the same 318-440. Slant six C bodies had a unique front stub. Otherwise it's pretty much bolt in. Especially if the drivetrain came from a C body.
 
Our cars do not have K frames. The front stub is the same 318-440. Slant six C bodies had a unique front stub. Otherwise it's pretty much bolt in. Especially if the drivetrain came from a C body.
Thank you for the info. I had people on fb pages saying a bunch of different things I’m just trying to find some trustworthy info. A guy recommended Schumacher for motor mounts
 
If you have a 904 trans in your car (most likely), you'll need a shorter driveshaft.
 
Agree that big block and small block subframe are same on c-body. No such thing as C-body K-frame. Engine mounts directly to top of subframe. 318 has different engine mounts than 383. Subframe is same, but engine mounts are different. Get the engine mounts with the 383/727 and you're all set.

John makes a good point. If you have a 904, you need the shorter 727 driveshaft. Try to buy that too.
 
Agree that big block and small block subframe are same on c-body. No such thing as C-body K-frame. Engine mounts directly to top of subframe. 318 has different engine mounts than 383. Subframe is same, but engine mounts are different. Get the engine mounts with the 383/727 and you're all set.

John makes a good point. If you have a 904, you need the shorter 727 driveshaft. Try to buy that too.
This guy is selling the engine tranny driveshaft and rear end. Should my rear end correspond to the new driveshaft or do I need to put the other one in
 
To be really specific about the mounts, the lower portion is the same between the V-8 engines and should be available as a replacement. The upper part of the mount is specific to the small block or the big block.

The upper mount, if it's not supplied, should be fairly easy to find as they are used across the car lines and over different years, but try to get the ones from the car if possible.

The trans mount is a simple matter of turning it around.

A couple things that will help... A parts manual will tell you what is used with the different combos and, of course, a factory service manual. Download them here:
MyMopar - Mopar Forums & Information - MyMopar Tools/Reference
 
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To be really specific about the mounts, the lower portion is the same between the V-8 engines and should be available as a replacement. The upper part of the mount is specific to the small block or the big block.

The upper mount, if it's not supplied, should be fairly easy to find as they are used across the car lines and over different years.

A couple things that will help... A parts manual will tell you what is used with the different combos and, of course, a factory service manual. Download them here:
MyMopar - Mopar Forums & Information - MyMopar Tools/Reference
Thank you. I really appreciate this and everyone on this forum. For a younger guy with not a lot of connections or deep pockets you guys make it easy to find the correct info
 
This guy is selling the engine tranny driveshaft and rear end. Should my rear end correspond to the new driveshaft or do I need to put the other one in
Depends on what rear end you have.
 
All of the wiring harness that relates to the engine? From the bulkhead forward. Trans kickdown linkage? Throttle linkage/cable? Other minor things which might be engine-family-specific?

The rubber insulator mounts for the engine and trans rear mount might be "there", but while you've got things apart, might be a good time to replace the old with newer ones?

Radiator? Hoses. Trans cooler lines? A/C lines, if equipped?

Mileage on the engine and how long since last run?

Front sway bar, as many 318 cars didn't have them as standard equipment, but B/RB cars did?

With the extra weight of the larger engine, might need to adjust the front torsion bars to compensate for it. Compare the rear springs, too.

The 383 was a factory production option for the car . . . as an assembly, with a cast of supporting pieces that came with it. Just don't expect to change the engine/trans and expect everything else to swap from the 318. BUT it all goes in the same place.

Enjoy!
CBODY67
 
This guy is selling the engine tranny driveshaft and rear end. Should my rear end correspond to the new driveshaft or do I need to put the other one in

The only way to tell is to measure the yoke at the front center of your axle and make sure it's same length and width as the yoke at the front center of his axle. If they are the same, you should also make sure that his driveshaft fits the yoke at the front of his axle by test fitting it. Then you'll know it fits yours.
YOKE
20190510_124311.jpg

20190510_125325.jpg
 
This guy is selling the engine tranny driveshaft and rear end. Should my rear end correspond to the new driveshaft or do I need to put the other one in

Depends on what rear end you have.

The only way to tell is to measure the yoke at the front center of your axle and make sure it's same length and width as the yoke at the front center of his axle. If they are the same, you should also make sure that his driveshaft fits the yoke at the front of his axle by test fitting it. Then you'll know it fits yours.
YOKE

I probably should of expanded on my answer...

Your car should have a 8 3/4" rear end and the outer housing, axles etc. will be the same as the 383 rear end. But! The center section may be different.

As @1970FuryConv has said, the yoke size needs to match. You'll have two choices... The yoke will either measure 2 1/8" across or 2 5/8" across. They do make adapter u-joints that go from one to another, but I'm not a fan of doing it that way.

The other issue is the size of the pinion shaft. If your 318 rear and the 383 rear have the same yoke size, everything will bolt up and you'll be fine... But! There's a good chance you are going to have the more desirable larger pinion shaft diameter with the 383 rear and the smaller pinion with the 318. Not a big deal, but if the new rear is the larger pinion, then it's a not a bad idea to swap center sections.

MyMopar - Mopar Forums & Information - Chrysler 8-3/4" Rear Axle Guide for more info on the differences.

You can identify the center sections by the number cast in the side. In the example below, this is a small pinion center section. 741 is the 1 3/8" pinion, 742 is the 1 3/4" pinion and 489 is the 1 7/8" pinion. Unless they've been swapped (it happens), your car will have a 741 or 742. Most likely, the 383 will be 742.
s-l1600.jpg


This isn't saying anything about gear ratios... Again, you need to look at what you have and what the 383 rear is. If it hasn't been messed with (again, it happens), there should be a tag on each rear where the center section bolts in that tells you the gear ratio.

Since the guy is selling as a package deal, you may be money ahead to buy everything and sort it out as you go.
 
I probably should of expanded on my answer...

Your car should have a 8 3/4" rear end and the outer housing, axles etc. will be the same as the 383 rear end. But! The center section may be different.

As @1970FuryConv has said, the yoke size needs to match. You'll have two choices... The yoke will either measure 2 1/8" across or 2 5/8" across. They do make adapter u-joints that go from one to another, but I'm not a fan of doing it that way.

The other issue is the size of the pinion shaft. If your 318 rear and the 383 rear have the same yoke size, everything will bolt up and you'll be fine... But! There's a good chance you are going to have the more desirable larger pinion shaft diameter with the 383 rear and the smaller pinion with the 318. Not a big deal, but if the new rear is the larger pinion, then it's a not a bad idea to swap center sections.

MyMopar - Mopar Forums & Information - Chrysler 8-3/4" Rear Axle Guide for more info on the differences.

You can identify the center sections by the number cast in the side. In the example below, this is a small pinion center section. 741 is the 1 3/8" pinion, 742 is the 1 3/4" pinion and 489 is the 1 7/8" pinion. Unless they've been swapped (it happens), your car will have a 741 or 742. Most likely, the 383 will be 742.
View attachment 319220

This isn't saying anything about gear ratios... Again, you need to look at what you have and what the 383 rear is. If it hasn't been messed with (again, it happens), there should be a tag on each rear where the center section bolts in that tells you the gear ratio.

Since the guy is selling as a package deal, you may be money ahead to buy everything and sort it out as you go.
Thank you very much for the info
 
Don’t forget the radiator. The 318 in my ‘70 (no a/c) came with a 19-incher, BB came with 22- or 26-inch rads.
 
So you’re saying that a radiator change should most likely be needed as well
Radiator: most important! When you change over to 383, make sure the outlet at the bottom of your radiator is on the same side as the inlet at the bottom of the water pump. If they don't match, you need a radiator that does match.

19", 22", and 26" are core width. You can measure core width by the following procedure:
The core is the central part of the radiator (between the tanks and the side-pieces) and consists of tubes and fins. Measure only the core to determine the size of the radiator.  Core Width A: This dimension is always measured from left to right (Driver’s Side to Passenger Side) as shown in diagram. Only the core is measured to determine the width of the radiator, do not include the side rails.  Rock Auto
down%20flow%20radiator.gif


If you have a 22" and no AC, you might be OK, provided outlet is on correct side.
 
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