Are 340’s rare

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33IMP said:
Dummy? I guess you HAVEN'T ever seen a dyno sheet. You know , the one where horsepower goes DOWN at the end?
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I was jokin with you, hence the "lol" at the end. Lighten up, Francis.
 
Dan the man said:
I had the chance a couple years ago to buy a standard bore 340 block, crank and heads for $500 and I passed, man was that dumb of me
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It's only dumb if that's what you need, myself I'd spend the money on the newer 5.9.
 
You can make any engine perform well. It is all about how much money you want to spend. I know of a Senior in Texas that has a 225 slant six that runs in the 10s in the quarter mile and if you take a standard bore 4.04 340 and put a 3.58 360 SB stroke in the block= 367 C.I.D. and everything else is the same---the 367 will win the race.
 
Not all 72 340s had cast cranks. Some 72 cars had 71 blocks in them and if they did---they came with a forged steel crank,forged steel I-beam rods and light not HEAVY cast aluminum pistons---8 and a half of course on CP ratio and smaller 1.88 intake valves. The 71 blocks had more meat and could be bored more. I once had a thin casting 73 340 that I degutted and regutted with forged 1051 steel crank and I rods and 10 and half cast aluminum pistons with a pair of cast in 67 for 68 model year 64cc X Heads. That TX9 73 Duster ran like a Raped Ape out of HELL!!! The Coppers used to call my car the Black Hole because I would always disappear from sight.
 
There are 340s out there tweaker fast back that will blow the doors off your 414 CID Engine A-body. 340s have a rep for beating big cubed engines and that includes your 414 CID Fish
If you really want a STROKER. Build a 48 degree SIAMESED 340 with 4.25 stroke by 4.20 Bore with W-2 Heads that flow 350+ that have 2.19 intake valves a very high lift solid roller camshaft and a 4 speed or better tranny. The standard will overtake the automatic just before the finish line. The standard 340 will not even come close to touching the 472 CID engine.
In a light body car you will run in the 8 seconds if your compression is high enough that is. I know, been there, done that.
 
I've got a .030 over 69 340n in a 67 B body just to bug the big blocks only in B body crowd :poke:. For the prices I see these sell for ill gladly pull it and sell it and buy brand new crate engine this one has rear seal leak anyway

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340sFastback said:
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...
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Obviously lighter reciprocating components will help with how fast/responsive an engine is.

Lots of other factors come to play that are also important. First and foremost, for an engine to rev up fast, against the weight of the vehicle, the engine needs to be powerful. Matched gearing and converter stall is obviously extremely important. Other factors such as compression ratio, cam timing etc.

I say the following, ignoring certain extreme examples of course.... We're not talking about RC car engines, and we're not talking about Diesel locomotives here...

Regardless of your bore stroke deck height combo, you're more than able to build a responsive, explosive, high rpm engine.
 
I'd just freshen it up and keep it... One thing I noticed is tend to see more 340s for sale than 360s ... I think that's because people will sell them especially if they can money out of 340... (Which they can) And probably why I see less 360s for sale they just don't Garner the price so people just keep them...They will make there money and buy a 318 build on the cheap with the 340 money they made... I'd say if your looking to hotrod on the cheap selling it is what most people do... But a 340 will make your car worth more... Even in a non-matching numbers car ya stick a 340 in a slant six car and it'll be worth way more had you stuck a 318 or kept the slant six in it... People willing to pay a little more money for a car with a 340 in it But if you're looking to hot rod on the cheap that wouldn't matter to you... Kind of just on what you want with your car and what your direction is...
 
How did I miss this mess of a thread I'm late to the party :)
 
For performance 318/340/360 all can basically take the same parts all can make more hp then most would build too, even a 273 bore size is capable of building enough hp to satisfy a majority of people.

Everyone has from a slightly to vastly different idea of what and ideal powertrain is and even will vary from project to project. Arguing what's best in an open unlimited criteria is impossible.
 
Now...here's one. Has any manufacturer ever built a square engine i.e. same size bore and stroke?
There is a reason the engineers pick certain dimensions.
 
ir3333 said:
Now...here's one. Has any manufacturer ever built a square engine i.e. same size bore and stroke?
There is a reason the engineers pick certain dimensions.
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Ford 400 basically a 4" stroke tall deck 2bbl Cleveland with big block bellhousing.
 
Full size cars and trucks from about 71 through the mid 80's. 4" X 4".
 
It's actually a 402, little 4" bore trick cid is equal to stroke without the decimal plus two.

3.00 = 302
3.25 = 327
3.48 = 350
3.58 = 360 etc..
 
Pretty sure '69 Buick GS 400 was a square engine. Going by memory I thinks its around 4 inch bore and around 4 inch stroke.
 
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