Are 340’s rare

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Cast crank, low comp. 340 is worthless to most of us hot rod guys unless you are going to make it a stroker.
 
33IMP said:
That's true too. Still would rather have a stroker than a stock stroke 340.
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And I would rather have a 422

stroker1.JPG
 
fishmens67 said:
Why so small. :D
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That's what she said.
All kidding aside.
When I got a virgin Mopar X Block (race block)
I had options of what to do with it.
1st off the casting says 318 and takes 318 mounts. Since I have only ever run 340 blocks and tossed all 318 I ran across had to find a 318 mount.
I had a early 340 someone gave me cracked block. And had steel crank 10/10, reconditioned rods and TRW standard forged early pistons/rings and balancer.
Machine shop had a cracked TA motor so could gave gotten the Heads, and valve train. They also had a de-stroked crank. So thought about making a 302 with a solid cam a size of 1968 manual 340 or 1 size up larger.
I saved the cash and used what I had stock 340HP high compression.
So stock stroke 340, stock 4.040 bore. Spent money on closed chambers album heads, and roller rockers.
I bet the 302 six pack would have had good street fun.
Other options possible since virgin race block could have also been stock 273 bore or 318 bore and left more meat for later.
But think only option back then would have been call and get costly custom 273 or 318 pistons
so could have also been a 273six or 318six. Who would have known.
 
Looks like i've ruffled more than a few feathers. The only point i was trying to make was a shorter stroke engine will rev quicker in engines similarly prepped with the same cubic inch and to a point will accelerate faster in a street driven vehicle.
 
Short stroke 340s have HEAVY pistons, HEAVY. 4 inch crank small blocks have short very lite pistons. Like I said earlier my 414 revs way faster then my stock 340 ever did. If I stomp gas pedal to the floor the 414 will scream up to 6,000 rpm faster then it takes for gas pedal to go down, like fraction of a second...
 
They are the next sought-after engine behind the 426 hemi. I'm amazed at the prices they are going for, that tells me they are rare. Less than 10 years ago I bought two original bore 340 blocks for $500 each, I'm glad I scooped them up...
 
SalC said:
They are the next sought-after engine behind the 426 hemi. I'm amazed at the prices they are going for, that tells me they are rare. Less than 10 years ago I bought two original bore 340 blocks for $500 each, I'm glad I scooped them up...
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Yeah, and what will they be worth 5 to 10 years out?
 
Back to the OP.

Again, compared to 2 barrel, and even 4 barrel "passenger car" engines like the 360, 383, and 400, the 340 is extremely rare.

That should be fairly easy to see.
 
Yeah and all 440 six pack engines had HUGE HEAVY *** rods and pistons and lost every race they were ever in. Yeah, yall go somewhere else with all that "only light reciprocating stuff" will haul ***. Morons.
 
I agree. A 408 revs nicely to 6000. Many warm 340 / 360's shift at 7800-8000. A long stroke engine
cannot physically rev as fast as a short stroke engine with the same displacement if they are similarly built.
It's physics.
 
I have to admit that the 340 has mystique, but I realize that any engine can be built to the same HP/CI level with appropriate parts. So a 360 will be better than a 340 and the 360 block is actually stouter than the 340 when pushed to the limit. But what cannot be replaced is the memories of all the runs I did with my 340 at SoCal drag strips in the late '60's and early '70's. I got my '68 Formula S FB 340 in June 1969 and had over 350 runs on it by the time I had 60,000 miles on it. Almost all were in the mid 13's with a best of 13.48 @ 105.38 in stock trim at OCIR (RIP!).
That is why I purchased 2 replacement 340's in the mid '70's incase I grenaded on, but never did. So now I have 2 spare engines for my 'Cuda which I still have after 54 years. The two spares were rebuilt at +0.020 as I always believed that you never remove more metal than necessary. Wish there were +0.010 over pistons, but alas!

Below is a photo of the '68 as it sits now in the shop waiting for seat tracks to complete the restoration. The second photo is some of my 300+ timing slips that I still have. Best time I found was 13.45 @ 104.65. Not bad for a stock 340. Only mods at that time were taking out the back seat (almost 50 lbs) and opening the cutouts that the original owner added way back in '68 before I bought it. I also like the 0.01 reaction time. I did cut a 0.000 once but couldn't find it.
So this is why I still like the 340 over the 360 even though the 360 can be built for less money in most cases.

Cuda with Windshild Installed.jpg


Timing Slips from OCIR.jpg
 
RLF Cuda said:
I have to admit that the 340 has mystique, but I realize that any engine can be built to the same HP/CI level with appropriate parts. So a 360 will be better than a 340 and the 360 block is actually stouter than the 340 when pushed to the limit. But what cannot be replaced is the memories of all the runs I did with my 340 at SoCal drag strips in the late '60's and early '70's. I got my '68 Formula S FB 340 in June 1969 and had over 350 runs on it by the time I had 60,000 miles on it. Almost all were in the mid 13's with a best of 13.48 @ 105.38 in stock trim at OCIR (RIP!).
That is why I purchased 2 replacement 340's in the mid '70's incase I grenaded on, but never did. So now I have 2 spare engines for my 'Cuda which I still have after 54 years. The two spares were rebuilt at +0.020 as I always believed that you never remove more metal than necessary. Wish there were +0.010 over pistons, but alas!

Below is a photo of the '68 as it sits now in the shop waiting for seat tracks to complete the restoration. The second photo is some of my 300+ timing slips that I still have. Best time I found was 13.45 @ 104.65. Not bad for a stock 340. Only mods at that time were taking out the back seat (almost 50 lbs) and opening the cutouts that the original owner added way back in '68 before I bought it. I also like the 0.01 reaction time. I did cut a 0.000 once but couldn't find it.
So this is why I still like the 340 over the 360 even though the 360 can be built for less money in most cases.

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Yours ran a lot better than mine.
Had a 69 Dart I owned in 1972 and 73
Had 3.55 gears and cheapy headers.
Best I got out of it was 14.23@ 99 mph, which was a hair quicker than some others back then that ran mid 14’s.
Suspect it was little better gear and the headers.
 
ir3333 said:
I agree. A 408 revs nicely to 6000. Many warm 340 / 360's shift at 7800-8000. A long stroke engine
cannot physically rev as fast as a short stroke engine with the same displacement if they are similarly built.
It's physics.
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Lol. A 408 revs to 7000 plus nicely
 
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