What 318s will work in a sweptline?

[sdhachey]

Me again, sort of a continuation of a previous post. I have a 1964 W100 with a worn out 318 poly in front of an NP420 4 speed (pretty sure it's the original motor). A rebuilt 318 motor is available locally, I'm told it is the original motor from a 1969 D100, had a 727 behind it. Will this work in my vehicle? What mods if any are needed?

Second question is about needing to understand the differences b/t car and light truck versions of both the 318 poly (like mine) and the 318 LA used in the newer sweptlines. A 318 poly from a 1965 Dodge Coronet is available locally as well. Is this an option? Is the car version of the 318 LA an option? I've gotten some conflicting info just talking about it. I would expect that the light truck version still had stronger internals, more durable, etc., and if so I would try to stick with the truck version (light or heavy duty 318). Please school me on the topic.

Thanks, I really appreciate the knowledge and help that people on this site provide.

[PwrWgnDrvr]

All are interchangeable. BUT, if in front of an auto, the crank will not be drilled for the pilot bushing needed for a manual trans. Poly exhaust manifolds are totally different from LA and cannot be interchanged.

[Hobcobble]

I would suggest looking at that LA318 out of the '69. It might have a drilled crank.
Worth checking... anyhow.

Secondly, there is a member who goes by "MoParLouie" who had a
'66 A318 Poly for sale a couple of months ago. He's in Moussup, CT.
If he still has it, he could probably give you information on whether
or not the crank is drilled. If so, you might swing a deal with him.
If memory serves... it didn't have a ton of miles on it...

Lastly, there is the possibility of using a crank flange bearing.
You'd have to remove some of the input shaft on the NP420, or find a
spare one from another member. Just a thought....
John

[sdhachey]

The crank difference is surprising. What's involved with modifying an auto crank to work with an NP420? If possible and practical, is it something a good machine shop can do w/o having to take apart the motor? I'd rather not modify the NP420 but I'd like to know more about that option as well. Thanks.

[PwrWgnDrvr]

I once stuck a big @#% bit in my 1/2" right angle drill, 1" bit IIRC, drilled the crank, hammered in the proper brass bushing, and that was that. (bushing 1" od, 3/4" id)

[Txas2step]

If the 318 you select does not have the deep recess in the crank for a pilot bushing , you can use a pilot bearing that fits in the large recess on the back of the crank. As John mentioned, you may need to nip off a bit of the input shaft so it does not bottom out in the crank. I will post the national bearing # when I find it. Chris.

http://www.rockauto.com/catalog/moreinf ... cc=1087680

[dodgeboykim]

I drilled a pilot bearing hole in a 400 crank by using a magnetic base drill sitting on a flywheel. Worked really good.

[Duh]

Hola Hachey

In order to under-stand what you have --- think of this:

The 1958 - 1966 A-318 ( this is your Engine ) has items that were used in later MoPar Small Block V8's ( LA-273's, LA-318's, LA-340's and
The LA-360's ).

Some of the quick items for all of the above are The Oil Pump, Valve Springs, The Cam Shaft Bering's, The Timing Chain & Gearing,

Now go back and mix in what you are reading here.




Rodger & Gabby
FltSgt@outlook.com
Colo Spgs

[HEtkind]

why don't you just pull the 318 poly and let a local machine shop rebuilt it?

Howard

[nytemuvr]

Hola Hachey

In order to under-stand what you have --- think of this:

The 1958 - 1966 A-318 ( this is your Engine ) has items that were used in later MoPar Small Block V8's ( LA-273's, LA-318's, LA-340's and
The LA-360's ).

Some of the quick items for all of the above are The Oil Pump, Valve Springs, The Cam Shaft Bering's, The Timing Chain & Gearing,

Now go back and mix in what you are reading here.




Rodger & Gabby
FltSgt@outlook.com
Colo Spgs

Interchange list.....viewtopic.php?f=5&t=34052&p=249082&hili ... ge#p249082

[sdhachey]

Posting a photo of the rear crank on a truck 318 poly. Is this the one equipped for a manual transmission? Thanks.

[PwrWgnDrvr]

Looks like it, but there is no pilot bushing in the center hole. If correct, the crank hole will be 1" and the bushing id will be 3/4"