ir3333
Well-Known Member
i think you summed it up once and for all.340's cost what they do because mopar guys love them and will pay the current asking prices!
Question about the price of 340s
- Thread starter Relax360
- Start date
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yellow rose
Overnight Sensation
yellow rose
Overnight Sensation
The 340 will always outrun a 360 all things being equal. Especially on pcar heads. Regardless of what all the gurus say, Rod to stroke ratio is a BIG deal, specifically on induction limited engines. The 340 is horribly induction limited and the 360 is even worse.
As already said, emissions and insurance killed the 340. The big main bearings on the 360 are a drawback. They did it because they new they were going to cheap out and use cast cranks, so they went to a bigger main journal to increase Rod journal overlap.
While you are spinning your tires, I will be hooked and gone.
I've seen so many underachieving strokers out there it's crazy.
Do the 340. You'll be happier. Unless you are one of those guys who is more impressed with smoking the tires than going fast.
As already said, emissions and insurance killed the 340. The big main bearings on the 360 are a drawback. They did it because they new they were going to cheap out and use cast cranks, so they went to a bigger main journal to increase Rod journal overlap.
While you are spinning your tires, I will be hooked and gone.
I've seen so many underachieving strokers out there it's crazy.
Do the 340. You'll be happier. Unless you are one of those guys who is more impressed with smoking the tires than going fast.
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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I got over 100,000 on my 367, and she's always ready for more.
I woulda killed at least a couple of , probably more, factory 340s, doing to them what I do to my 367. Actually I did kill several 340s lol, not doing the half of what I do to the 367.
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If building a stroker, no one will be able to notice .040 larger bore, so use up those 360 blocks. If you want yet another 340 vs 360 thread, once again I'll say the 340 is my favorite, having had both. Heck, I'll even take a 273 over a 360. As a matter of fact, I have. I remember test driving a HP 360 Road Runner Volare, and deciding my 273 was faster. Went out and redid the interior of the 64 Cuda, custom leather seats and all. I sold off all the 360's I had years ago and kept the 340's and 273's. Go figure? As for junk Chevrolet engines, I'll take a 327 or 283 any day over a 350.
A Pontiac @ 8K RPM? Not very many times will you get away with that! I have scattered a 389 and a 421 in my life, way bellow that number.
hi mr. jburch,
well... where to start...
first of all, "tachometers" were not common items until the 1964 GTO appeared. they were more common in foreign sports cars than american cars before the mid-1960's. because the 64 GTO became such an instant sales hit, all the car divisions started gearing up "race car" option packages for one or more of their standard vehicle lines. chevrolet entered the "fast car" wars with their "SS" option package available on the 1965 Impala, chevelle and "Chevy II" (later known as Nova). dodge offered the "RT" option on their 67 coronet line; plymouth offered the "GTX" package on their Belvedier line and the "Formula S" option on the Valiant Barracuda. ford offered the "GT" package for the mustang and the "GTA" option on the fairlane. the GTO Pontiac became a separate "race" car in 1967 (not just an option package for the tempest) and the big pontiac bonneville had a performance package which included a tach. however, ALL factory tachometers in the 60's and 70's were WILDLY inaccurate! it was very common to see factory tach needles sweeping and bouncing all around the dial as the motor got to high RPM's. that is primarily the reason why after market SUN Tachs became an immediate required item for any serious street racer.
because the factory tachs were so inaccurate, relying upon them for high RPM shifts was really a risky business. another problem was that the factory tachs would often go to "9000" RPM which was an IMPOSSIBLE number for ALL stock engines at that time. believing that "more is always better" lots of guys would try to shift their 67 396 Chevelle at 7000 based on the factory tach - and then when they would miss second gear, the engine would go "boom!!"
one of the reasons why GM lovers today are able to restore their 60's "big block" GM cars with "factory warranty blocks" is because GM produced A LOT of non-number stamped "warranty" big blocks from about 68 through 71. the company had to do this because kids were "blowing up" their 396 and 427 motors on a pretty regular basis.
GTO 389 motors were commonly referred to as "boat anchors" in the late 60's early 70's because so many of them were at local junk yards with big holes in the sides of the blocks where one or more connecting rods decided to exit on some high RPM race one night.
i grew up in the northern part of west virginia not far from pittsburgh and "muscle" cars were very common in that area. it was a common fact that it was "hard" to "blow up" any of the small block motors in the 60's and early 70's and it was fairly "easy" to blow up "a big block" - ANY big block.
one last thing to remember, the manufacturing standards of cars in the mid-60's and early 70's were COMPLETELY different from what they are today. those were the days of frequent strikes by the United Auto Workers and labor disputes often showed up in the build quality of the cars. there was really no such thing as "fit and finish" requirements for cars then. gaps in body panels were measured by if the door, hood or trunk would just shut. front and rear grills were often not aligned with body lines. it was true that soda cans were left inside doors. GM had a big strike at their at their Lordstown plant in 1972 which lasted over six months. it was not uncommon for unhappy workers to produce sub-par vehicles in an attempt to get back at the company.
another bit of history on old muscle car engines is that they were all produced "on the line" like every other engine. you could actually get a chevy 427 big block installed in your vehicle "from the factory" long before the day of the 67 Corvette or Yenko Camaro arrived - all you had to do was order a new 1966 5 ton C-50 Chevy Dump Truck. there were no "special" engine divisions back then like ford's "Special Vehicle Team" (SVT) or chevrolet's current "hand built" corvette engines. 6 cylinder and V/8 engines produced by all of General Motors Divisions were just "car parts". the guys building these motors didn't care any more about a 396 going into a SS Chevelle or a 389 going into a GTO than they did building a 292 six destined for a half-ton pickup or a 327 going into an impala station wagon.
so yes, big block motors in the late 60's and early 70's DID fail on a much more regular basis than any of the small block motors produced at that same time. it was a matter of "Physics" + "stupid teenagers" + "UAW engine builders that really didn't give a ****."
yellow rose
Overnight Sensation
Yep, you scatter a Pontiac long before 8k. It has the oil timing off like a Chrysler, the mains are big enough for a 7.5 inch stroke and the blocks are not that tough.
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People ask so much because stupid people pay that much. Like a rusted slam the FARK out Duster for 10K or a seized small block for over 1500. Stupidity at its finest. A 340 is worth zero more than any other small block, unless you happen to have what it came out of. Anything else is someone trying to get one over on you. Don't let it happen. As others have recommended, find a 360.
I have to respectfully disagree. One look at the lifter bores hung out to dry in a Poncho motor and you can see just how weak those blocks are. Several bores are completely unsupported.
yellow rose
Overnight Sensation
Sorry RRR. My sausage like arthritic fingers missed the word not in there. I'll correct it.
That's for keeping an eye on me.
I thought I did scatter it, surprised I didn't, it lived of for another 4 years before it got pulled down again for a bore job and new pistons.
I heard about the crappy Pontiac blocks so I did a search and was shocked to see how cheesy those lifter bores look! Some things you see just make you wonder what the hell the engineers were thinking. It would have only added 5 lbs or less to cast those blocks with more iron around the middle. What a dumb *** design.
yellow rose
Overnight Sensation
5 pounds times 500,000 blocks is a big number. I'm not good at math so you can add it up for us lol.
That's where bean counters have much more control over engineers than they should.
I'll say this...........crappy or not, Mickey Thompson was the first American to go over 400 mph at Bonneville, using Pontiac engines in his car; this was several years before the Summers Brothers went over 400 with the Goldenrod.
Dartswinger70
Well-Known Member
'Cause the 340 was only made for like 5 years, and in half that time they were detuned/smogged out by the EPA. So for like 68 till early 71 (or something like that, I know Im in the ballpark with the timeline) the 340 engines were the best ones put out by the factory. A 73 340 is still good to have , but it is not the same monster as an early 340.
when a person gets "old", lots of memories about stuff that they experienced "in their youth" begin to get distorted. "fun" times get blown out of proportion to how much "fun" was really experienced at the time and "bad" stuff "back then" turns into "near life crises." my memory tells me that ALL "food" tasted MUCH better in the 60's and 70's and, of course, my memory of the long-haired, 16 year old girls at my high school wearing mini-skirts (and "micro-minis) offer a great deal of entertainment while staring off into space sitting in my comfortable TV viewing chair. but i HAVE TO SAY THIS: i DO remember how my 1968 340 4 speed fastback Barracuda Formula S with a 3:91 rear gear ran .... it WAS fast!! if i was pulling away from a red light in first gear and just planted my right foot into the loop pile black carpet trying to kick the gas pedal through the fire wall - the force that would throw me and a passenger back into those expensive vinyl covered bucket seats was overpowering. i used to do the $5.00 bill taped to the dash trick - you old guys know this drill. you tape a bill to the dash and then tell the passenger "when i launch this car, if you can reach up and grab that bill, you can have it." no one was ever able to grab that bill in my "340" Barracuda. there were lots of cars that would "accelerate quickly" back then. but then there were a few others that when you launched from a standing start and began grabbing gears, the experience was right on the edge of being frightening. that's the way a lightly modified 340 mopar was. if you had a 340 mopar and put a better manifold with a big holley carb along with a good set of headers and then topped if off with a 3:91 rear gear, you ended up with a street car that would scare almost anyone sitting in the passenger seat any time you wanted to.
i know old guys all have their favorite car. and i know our memories get a little less accurate the older we get. but i "remember" my 68 Barracuda - it scared my guy friends and it made my "girl friends" "giggle" and get "romantic."
i know old guys all have their favorite car. and i know our memories get a little less accurate the older we get. but i "remember" my 68 Barracuda - it scared my guy friends and it made my "girl friends" "giggle" and get "romantic."
ir3333
Well-Known Member
...and on the seventh day, God created the 340!
Hey you can kill a stock 340 turning it 6000+ RPM, it's not going anywhere there, but have fun.
They were dead in the water at 5500 at best. Only reason to turn them higher was if you were in high gear running out the back.
They were dead in the water at 5500 at best. Only reason to turn them higher was if you were in high gear running out the back.
I was referring to that in my post. It's even the later cast crank engine. Dumbassness at its finest.
They were hardly monsters. It was the whole package. A 340 in a Dart or Duster was a terror a lot of big block cars could not handle. Put that same 340 in a Challenger, Charger or Road Runner and the game is nowhere near the same.
I'll give you this as an example. The 1970 LT1 Camaro was rated (conservatively) at 360 HP.
Those cars weighed around 3300 pounds give or take. Couple that with an M22 close ratio Muncie 4 speed and optional 4:10 gears and there was probably not a 340 car on the planet that could take one, all else being equal. Stock for stock.
11:1 compression. 346 degree advertised duration, .458 lift solid lifter camshaft. Bow Tie heads.
Only way a 340 car of any kind will come around that is driver error on the Camaro's part or parts breakage. Otherwise, it ain't happenin.
Sorry to break it to you, but that's the truth.
Those cars weighed around 3300 pounds give or take. Couple that with an M22 close ratio Muncie 4 speed and optional 4:10 gears and there was probably not a 340 car on the planet that could take one, all else being equal. Stock for stock.
11:1 compression. 346 degree advertised duration, .458 lift solid lifter camshaft. Bow Tie heads.
Only way a 340 car of any kind will come around that is driver error on the Camaro's part or parts breakage. Otherwise, it ain't happenin.
Sorry to break it to you, but that's the truth.
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