Looked at Some Motors Today

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DA4AD

DA4AD

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I had a look at some small block mopars today and I have a few questions,
1) 1973 340 long block, stock rebuild, .060 over on the cylinders, X heads. Is this a usable block at .060?
2) 1969 340 short block, standard bore, forged crank, stock pistons. What's this worth?
3) 318 truck block (block only) bored 4.070, four bolt motor mounts. I've never seen a block like this. He say it's stronger than a 340 block? Is this true?
:burnout:
 
DA4AD said:
I had a look at some small block mopars today and I have a few questions,
1) 1973 340 long block, stock rebuild, .060 over on the cylinders, X heads. Is this a usable block at .060?
2) 1969 340 short block, standard bore, forged crank, stock pistons. What's this worth?
3) 318 truck block (block only) bored 4.070, four bolt motor mounts. I've never seen a block like this. He say it's stronger than a 340 block? Is this true?
:burnout:
Click to expand...

number one sounds like junk, number 2 sounds like it might be usable and number 3 sounds like a chrysler industrial engine like RV or campervan
 
1. I don't know fer sure if a 340 bored .060 is junk or not but the heads are usually pretty good.

2. a short block 340 is worth betwixt 500 and 1000, as long as it still spins.

3.Cain't really saw about the supposed truck block,...Got any pics?
 
What yr is the truck block? The earlier 318's are known for having thick walls. 4.070 is equal to a 340 +0.030.

I was stripping the k-frame out of a '74 Valiant a few days ago and the driver's side mount was four bolts... I don't think I'd ever come across that before. I thought it was unusual, but now after your question, I gotta go back and find out more about the block, just to satisfy my curiousity.

Mike in FL
 
just had my 71 340 block sonic checked when it was already .030 over, my machinist told me there was tons of meat in the bores and .060 over would be fine, though louder (more engine noise, not exhaust concerned) due to the more you bore the more loose they tend to be, and possibly hotter, but im not worried about it, i wouldnt be too concerned with .060 as long as the bores and honing jobs look good
 
dodgedartgt said:
What yr is the truck block? The earlier 318's are known for having thick walls. 4.070 is equal to a 340 +0.030.

I was stripping the k-frame out of a '74 Valiant a few days ago and the driver's side mount was four bolts... I don't think I'd ever come across that before. I thought it was unusual, but now after your question, I gotta go back and find out more about the block, just to satisfy my curiousity.

Mike in FL
Click to expand...

Mike,
This 318 motor had four bolt motor mounts on both sides.
From what I've been seeing on this site a sonic test defiantly sound be done on the 73 block, some have had good luck while others Haven't at .060.
 
jaimus said:
1. I don't know fer sure if a 340 bored .060 is junk or not but the heads are usually pretty good.

2. a short block 340 is worth betwixt 500 and 1000, as long as it still spins.

3.Cain't really saw about the supposed truck block,...Got any pics?
Click to expand...

Sorry, no pictures.
 
My .060 over bored 340 ran just fine until i sucked an intake valve. (my fault:violent1:) and it went thru the cyl wall.

It like to run hot and i fugured out why. major core shift!!!!!

When you shim your valve springs.........Make sure you seat the lock!!!!!:sad1:

That stunt cost me a block, piston, rod, and a cyliner head!

The 318 isn't a poly block is it?
 
Cudafever said:
My .060 over bored 340 ran just fine until i sucked an intake valve. (my fault:violent1:) and it went thru the cyl wall.

It like to run hot and i fugured out why. major core shift!!!!!

When you shim your valve springs.........Make sure you seat the lock!!!!!:sad1:

That stunt cost me a block, piston, rod, and a cyliner head!

The 318 isn't a poly block is it?
Click to expand...

What's a poly block?
 
Sounds like an early (Poly) 318 block.
 
Poly block refers to first gen "A" motor's, Poly meaning Polyspherical head design. Allpar lists the small blocks as manufactured between 64 to 67. 2nd generations "LA" small blocks were manufactured from 67 to 90. 273,318,340 and 360's motors are "LA" engines. These 2nd gen LA motors were very common as they were put in eveything from trucks and A Bodies to the bigger Cop cars. Contrary to popular belief, not all Big cars had big blocks.

I believe the Magnum small blocks were manufactured from 1991 on up and became the engine of choice for todays younger crowd.

I've always believed that if you took an "LA" motor and a GM 350 and built them similarly, meaning that dollar for dollar and pound for pound the build was as equal as possible, the LA mill would smoke the GM mill...and my GM friends tend to agree.

Go to http://[URL="http://www.allpar.com/mopar/poly"]www.allpar.com/mopar/poly.html[/URL] for a more comprehensive discription.
 
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