340

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You mean because of the difficulty of finding a good used one.
Some guys have bored 318s out to 340 size
You can bore a 360 out to 340 size.
If you really want a 340 put up a want-ad. If you can't find one Pm me; I have several you can chose from.
 
You mean because of the difficulty of finding a good used one.
Some guys have bored 318s out to 340 size
You can bore a 360 out to 340 size.
If you really want a 340 put up a want-ad. If you can't find one Pm me; I have several you can chose from.
Careful with believing this blindly since the 340 bore is a 4.04 and the 360 is at a flat 4 inch doesn’t automatically mean the 360 can take a .040 boring.

This applies even more so to a 318 that is at 3.91. To get to a 4.04 is a .130 over bore.

BEFORE YOU BORE ANYTHING, SONIC CHECK IT AND SEE HOW THIN YOU WILL BE AT THE NEW BORE SIZE!!!!

AND Don’t believe anyone that says there 318 went to a 340 bore unless you can see and measure it YOURSELF! Because it is more than likely a bunch of horse **** served to you on a silver platter.

The only person making a Chrysler small block is “Ritter Racing.” Check the block out at Hughesengines.
Hughes Engines

Adjusted cid listing
 
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Because everyone wants a thousand DIFFERENT blocks! No manufacture will attempt that. Let's settle on one size and work around that.
 
I've had a standard bore, absolutely cherry 340 block on the classifieds here for sale for a while. It's not like you can't find them if you look.
 
I've had a standard bore, absolutely cherry 340 block on the classifieds here for sale for a while. It's not like you can't find them if you look.
I seen this ([FOR SALE] - 340 shortblock)
And thought about taking a extended vacation to test out my new trucks abilities.....
Very tempting sir! Very!

How much does a 340 block go for nowdays,or a shortblock? Lets say ,030 over .Any idea.

The above is accurate in general. If he were here, it is possible to get $50 - $100 more due to my odd location and high scrap rates/overturn on metal. There are no places like pick anoart or anything more than a few years old. Prices for junk yard engines rival new rebuilt prices.
 
AND Don’t believe anyone that says there 318 went to a 340 bore unless you can see and measure it YOURSELF! Because it is more than likely a bunch of horse **** served to you on a silver platter.
Oh, I'm sure it has been done. Too many experiments have been done out there with this stuff to not have been done LOL. Seems like I read about it here some time ago...

Last time I shopped for 340 block, they were going for around $400-600 typically in the mid-Atlantic region. That was 2-3 years ago.

Easy to understand why to not to make 340 blocks. The real cost of starting production is 10's of thousands of $$$$$... both in time invested and tooling. Not anywhere near worth the risk for such a small market segment. It's not a wise place to invest one's time and $$, when you can take the same investment and make a lot more $$$ on a Chevy or Ford or even a SBM 360/5.9 part and with low risk. It's dumb TO do it. (FWIW, I've run my own business for 15 years....)
 
Oh, I'm sure it has been done. Too many experiments have been done out there with this stuff to not have been done LOL. Seems like I read about it here some time ago...

Last time I shopped for 340 block, they were going for around $400-600 typically in the mid-Atlantic region. That was 2-3 years ago.

Easy to understand why to not to make 340 blocks. The real cost of starting production is 10's of thousands of $$$$$... both in time invested and tooling. Not anywhere near worth the risk for such a small market segment. It's not a wise place to invest one's time and $$, when you can take the same investment and make a lot more $$$ on a Chevy or Ford or even a SBM 360/5.9 part and with low risk. It's dumb TO do it. (FWIW, I've run my own business for 15 years....)

I know a place that takes them 318’s to a 4 inch bore if they pass the sonic check.
I have read that it has been done before.
But until I measure it myself.......

Seriously, a .130 overbite? Maybe. Depends on the sleeve used.
 
I know a place that takes them 318’s to a 4 inch bore if they pass the sonic check.
I have read that it has been done before.
But until I measure it myself.......

Seriously, a .130 overbite? Maybe. Depends on the sleeve used.
I have personally laid my eyes on ONE 68 vintage 318 block that was bored to 4.040, it was a dirt track engine from many years ago
 
And you know what problem that claim makes now right?

Now where going to have 30 or so crying there 318 block could go that far much less to a 4 inch bore!

LMAO
 
You mean because of the difficulty of finding a good used one.
Some guys have bored 318s out to 340 size
You can bore a 360 out to 340 size.
If you really want a 340 put up a want-ad. If you can't find one Pm me; I have several you can chose from.

Pm me what you have... I just bought a new 4 inch crank last week and it needs a home
 
I haven't looked at them in maybe 30 years. They are all 68 to 71 and I measured them back in the early 80s all at or near stock bore, when they came out of the washer. With passing time I imagine they will all clean up with .010/.020 overbore. I need to keep a certain 69er that belongs in my FormulaS project car. I think there are still 3 or 4 left,buried deep under a mountain of other stuff.
I had five of 340s; two Ds(68) and one each E(69),F(70) and G(71).
Records also show I have four teeners; a68,a 70,a 71,a 73, and an 84truck motor
and one 360 from a 77van.
 
I would be interested in any block the would cleanup at 30 over...let me know what you can dig out.
I will do a build with it this winter and post it here in the site. The only other 340 I have is a good runner that needs rings so I would perfor if I could get another block.
 
Iv read a couple of accounts where ppl claim to have bores a 318 to a 340. There was a guy on fb swore that he had one even read it on another forum. I'm a little hesitant to believe it. But I'm not going to call anyone a liar. One guy said he tried it on several different blocks at least a dozen and only found one that made it and didnt crack and it was a 67 model block he claimed that only pre 68 blocks should even be considered and even then it was a long shot. But he claimed that he did it!
I seen this ([FOR SALE] - 340 shortblock)
And thought about taking a extended vacation to test out my new trucks abilities.....
Very tempting sir! Very!



The above is accurate in general. If he were here, it is possible to get $50 - $100 more due to my odd location and high scrap rates/overturn on metal. There are no places like pick anoart or anything more than a few years old. Prices for junk yard engines rival new rebuilt prices.

If you make the road trip you will have to stop by and chat for a while you will drive right by me on the way to nc!
 
It is possible but it would be rare to find.
The older Poly 318 engine has been known to have very thick cylinder sleeves.

I’m not saying lier, I’m saying proof or it didn’t happen!
LMAO
 
The one I saw, blew up, and I'm a big fan of thick cylinder walls, not max bored thin ones
 
The one I saw, blew up, and I'm a big fan of thick cylinder walls, not max bored thin ones

I did one 4.040. Cast in 12-23-71 for '72 year HM318 39330111 and had 4 ears for the mount brackets to bolt to. Especially flat sides on the outside.

It's a 3.91circle, .065 removed from id surface... in a cylinder that equates to .130 overbore 4.040
 
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