Pick a block

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K.O. SWINGER

Meeting in the alley since 1976
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I'm curious to see which block is favored and for what reasons. My question is if you had your druthers and could have a block delivered to your house for your next build which factory block would you choose? Assuming each block is a good rebuildable core would it be a la360 or LA roller possibly a 340 block or perhaps a magnum. Mention your intent it can be stock stroke or stroker the choice is yours I would like to know why you pick the one you pick. Let's take ta 340s off the table please.
 
Pre Magnum 360 roller
Build intent? Everything and anything. Mild to hair raising wild.
My imaginary block. Same as above only a 340 main, with the ability for a safe 4.250 bore. Siamese cylinders please!
Build intent, same as above.

The Magnum block is a newer & stiffer better machine and probably faster block with tall lifter bores with plenty of meat around them.
 
Hey rumble would that be a stroker build with the LA 360? How about a 8 sleeved 340
 
The Magnum. Simply because it's the newest generation small block. Stands a better chance of being an excellent core. JMO
 
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My two cents: the one most readily available to you. Magnums are a dime a dozen, the older blocks are getting harder to find. I have two 340s that I'm on the fence about selling to cover the costs of building a Magnum or my late '70s 360. Probably won't though.
 
Hey rumble would that be a stroker build with the LA 360? How about a 8 sleeved 340
Question 1; Any C.I.D.
Question 2; Around here, the cost of sleeving 8 cylinders is more than stupid expensive. For the price, I’d gamble on a rusty pictured 340 block that has the description of “Left outside to rot the last 30 years, ....”
 
Question 1; Any C.I.D.
Question 2; Around here, the cost of sleeving 8 cylinders is more than stupid expensive. For the price, I’d gamble on a rusty pictured 340 block that has the description of “Left outside to rot the last 30 years, ....”
No I'm talking about quality cores, around here there's a guy up next to Portland that I met at woodburn drag strip that are pretty into sleeving he quoted me a price of $700 but that was a couple years ago
 
My two cents: the one most readily available to you. Magnums are a dime a dozen, the older blocks are getting harder to find. I have two 340s that I'm on the fence about selling to cover the costs of building a Magnum or my late '70s 360. Probably won't though.
Do it, they are getting pushed aside for Gen 3 hemis as we speak. No one is building a "hot 350" anymore as the LS is so much better in every way. Same goes for the 302, the coyote modular motor is eclipsing all the Windsor block builds. Time to face reality.

Id choose a 5.9. Roller cam ready, superior heads, 1.6 rockers...newer castings. And I'm an LA user since 1985.
 
Do it, they are getting pushed aside for Gen 3 hemis as we speak. No one is building a "hot 350" anymore as the LS is so much better in every way. Same goes for the 302, the coyote modular motor is eclipsing all the Windsor block builds. Time to face reality.

Id choose a 5.9. Roller cam ready, superior heads, 1.6 rockers...newer castings. And I'm an LA user since 1985.

I can't disagree that they are, but I have also thought about a stroker 340 for the '68 Valiant, just to have a nice street cruiser with decent power. I'm not ready to move onto the G3 stuff, I love the small blocks too much lol But I do agree that it seems to be getting very popular. Enough so to grab the attention of Holley for swap parts.
 
Stoke a 360, save the 340 for the resto crowds money to find a way into your pocket. I've owned 3 and made money on selling every one of them, even an O-ringed .060 over sold.
 
Any of these...

LA roller 360@.020 4.020

Or a 340@.020 4.060

Or an early mag with the deck oil feed for la heads@.020 4.020

340's need main bearings mod'd,slotted to align with the blocks feeds that are slightly off from the bearing holes.
360 just drop in, the have wells/bathtubs in the saddles at the feeds.
 
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No I'm talking about quality cores, around here there's a guy up next to Portland that I met at woodburn drag strip that are pretty into sleeving he quoted me a price of $700 but that was a couple years ago

Im not fully getting at what your asking. Sleeving a good core?

Quality cores of what? 340’s? If you can get one, build as you see fit. IDGAF what cid it is. As long as there is a good cylinder wall. Then your good to go.

Now sleeving 8 cylinders @$700 (I was quoted $800 last year - LMFAO!) is a price you think is OK, then go for it. I’ll take a chance at another block.

IMO, the best block to work with is a pre magnum 360.
Then the 318 IF you can not get a good 340 core.
 
Im not fully getting at what your asking. Sleeving a good core?

Quality cores of what? 340’s? If you can get one, build as you see fit. IDGAF what cid it is. As long as there is a good cylinder wall. Then your good to go.

Now sleeving 8 cylinders @$700 (I was quoted $800 last year - LMFAO!) is a price you think is OK, then go for it. I’ll take a chance at another block.

IMO, the best block to work with is a pre magnum 360.
Then the 318 IF you can not get a good 340 core.
Yes I see what you are saying,if it was a good block there's no need to sleeve I'm just curious of others take on factory blocks.
 
I prefer la blocks only. I like to keep the style of engine for the period of the car. In my case 1975 dart sport 360. I got lucky and found a 1975 chrysler cordoba 360 and it donated it's guts!! So ended up with same year engine. I am looking for another early 70's 360 block with mains or with crank. For spare if anyone has one.
 
I dont know anything much about the differences in the blocks. Tony says get a 360 if you wanna go fast so I'd opt for...

Another 340 with the biggest bore and stroker kit I could get for it that would still allow me to drive it all over town.
 
I am a die-hard 340 guy, my car is a 340 swinger and I have an 1969 340 in it but I also have a 1990 roller la low miles that I have been keeping because I think it's a great foundation I am beginnin to compile parts to go through my motor again and need to make a decision if I'm going to move away from the 340 platform probably not.
 
My 1975 360 core engine. Because I have it... Get the caps strapped along with main with studs and a 3.79 inch crank. Because with a .030 overbore, 387 c.i.d. is still plenty enough to exceed the long term horsepower limit of the block with a good set of heads. On a side note, I'm starting on a 360 LA roller short block I'm putting together for a friend on a trade. At 58,000 miles of severe truck usage, the cylinder walls still have the full crosshatch. Kissing the bores with a fine grit glaze breaker hone 10 to 20 strokes is all it will take to knap the bores in enough to seat a fresh set of rings. I don't know how either, because the crank and bearings were trashed out...
But my first choice would be an early seventies 318-3 block with its original steel crank for a 4 inch bore 333 incher. Add in some Milodon main caps with studs, H beam aftermarket rods, J.E. flat tops, and some lightly ported W2 heads.
 
Pre Magnum 360 roller
Build intent? Everything and anything. Mild to hair raising wild.
My imaginary block. Same as above only a 340 main, with the ability for a safe 4.250 bore. Siamese cylinders please!
Build intent, same as above.

Definitely (in my little opinion) would have been an ideal La block . let's have a few cast for us I'm in.
Large LOLS'
 
I need a large bore for a race motor so i need a 340.that will go to 4.250....
 
.210" overbore by the math, but I'm not sure that any are thick enough to go that far. I would definitely sonic check the block to see how much overbore one could go.
Only a sonic check will tell you what can or can not be done. I had a 340 tank with a .020 over bore. Had it been sonic checked to begin with instead of assumed, it never would have been machined. The wall thickness in cylinder #8 after boring was a huge .034 thick.

Amazing huh?!?!
 
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