Earlier 340 Internals in 1973 318's

Came across and ad on Craigslist. A guy has a 73 318 long block for sale, claiming that starting in 73 Mopar started putting earlier 340 internals into 318's. ????

I think he doesn't know his a$$ from his knee cap, but then what do I know?

Also, weren't the 273, 318 and 340 cranks and rods the same?

As long as it was balanced it should be fine. See if he has proof /receipt of the work .

It's a used long block. Doesn't look like it's ever had work done to it. He is claiming that ma mopar put 340 internals into 318's, starting in 1973.

no

Well, some stuff swaps over, bolts, timing covers, brackets, oil pans, etc.

But.........

Do not believe everything you read on the internet or elsewhere.

At times, skepticism is a virtue.

No mopar didn`t do that. I misread and thought you said he installed 340 internal parts. The 340 went to a cast crank, special balancer around 73 but it was different from the 318. 318`s remained unchanged from what I remember.I would shy away from that deal.

What Mopars4ever said on the receipts/balancing, go check it out skeptically, it may be a good deal (nothing ventured nothing gained). EDIT if parts were swapped I would assume it was balanced).

I had a 72 318 that had those lighter rods like the 273's had, maybe that's what he was trying to say

rod # 3418645 was used in 73/74 318 same rod 71/73 360 and also 72/73 340 with cast crank .
Non of the 318 & 340 cranks have the same part #'s

The forging part numbers might be the same but the finished part numbers wouldn't be. IIRC 318's and other small blocks had a pressed wrist pin, whereas 340 rods all were bronze bushed and the pistons had floating pins with C Clips.

For crying out loud, he's trying to say the seller is claiming Chrysler built 318's with the same crank and rods as the 340 from the factory. Not that the seller built it that way.

He's not going to have and receipts or paper work showing balancing.

Super Cuda why don`t you find another place to annoy people.

source i have says 273 /318 and all 340 up to 73 had floating pins . 318 went to pressed pins in 74 and all 360 had pressed pins .

Looks like seller corrected his listing.

The power steering pump might be a good grab.

https://portland.craigslist.org/mlt/pts/d/sherwood-mopar-318-la-long-block/6938547508.html

Was...Nearly complete 73’ dated Mopar 318 LA motor with all accessories pictured! Would be a good core motor to rebuild. 1973 is when Mopar started putting the earlier 340 engine internals into their 318 motors. This makes for a great rebuild or stroker! It has a

Now..Nearly complete 73’ dated Mopar 318 LA motor with all accessories pictured! Would be a good core. This makes for a great rebuild or stroker! I have never ran engine so it should be rebuilt before use. Sold as core. Read Less

Yep, that's the one. Perhaps another of the local Mopar guys called him on it as well.

All the 318 had the same bore from beginning to end, stock is 3.91. correct
All 340, 1968 to 1973 had 4.040 bore size, correct? Me thinks that the 340 piston will never fit in a 318, will they
Another dummy trying to off his junk as something special

I bought a 70 318 once for a core with a rod knock for the forged crank, opened it up and it had 4.070 bore TRW forged 340 pistons in it. I still have the block under my shelf as the bores still look great, I just can't convinve myself to put it back together seeing how the normally 165 # block now weighs 122# and the bores sound like glass when I tap on them with my fingernail.

I thought the only motors of that era to get bronzed bushed rods and floating pins were the 340 and the Gen 2 hemi...

his source is right, 273, 318 and 340 had bronze bushed floating pistons till around 73

Come on guys this is simple basic mopar stuff. And its easily found on the web as well.

Keep in mind if you ever build with a cast 3.31 crank and lighter rods grab a early 318 crank that used the thin rods. Although the weight difference isnt as much as on would think or by the way they look side by side the early vs later rods.

But here is a basic bushed 273/ early 318 rod.

Moparts really blows on real world normal guy tech, im not a member of fabo but anytime I need to find good solid usable info, the search engines almost always point to fabo.

https://www.forabodiesonly.com/mopar/threads/273-318-connecting-rod-weights.380169/

As I remember, the 273 and 318 rods had the bronze bushings, but the pins were pressed into the pistons, the 340 piston pins were floating in the 340 pistons and in the rods. The 340 piston pins were held in place with the lock clips.
The pressed pins in the pistons on the 318 and 273 is what is confusing most of the guys. You had to have the pins pressed out on the 318s and 273s. Gene

I have torn down a bunch of 318's in my youth. I never saw one with floating pins.

Go find some untouched early 318s and learn.

One piston is a 69 here the other is a 70.

but the pins were pressed into the pistons................. HUH?

Thats crazy talk..... yea pressed in by hand them insert clip. I guess my three fingers are a human press.

Hello, it was all just like the 340 floating setup. Look at the pics I posted.


Just like a 340 the early ones ALL slid together and were held in by clips.

Here, look at the factory part numbers, chase some down and DONT for your retainer clips.

It's because they made it such a pain in the butt to post pics and such, I know I post a lot less stuff now because of it.