Today, dollar for dollar, is the 318 faster than the 340 ???

would you agree ?

  • yep, the 318 wins if buying and building for under 3k

    Votes: 48 41.7%

  • Nope, the 340 always has and always will beat the 318

    Votes: 57 49.6%

  • Actually, never thought about it like this... Good Point !

    Votes: 10 8.7%
  • Total voters
    115
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mygasser said:
so as i said when you build your 340 with better parts (and there are now better parts out there than stock 340 parts) it's not a 340 any more?
listen to yourself :rofl:
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You miss the point what is this called "diverting"?:) Ill say it plain, if you cant get 320 Horse out of your 318 with three grand don't even bother...
 

Dartswinger70 said:
You miss the point what is this called "diverting"?:) Ill say it plain, if you cant get 320 Horse out of your 318 with three grand don't even bother...
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why are you so convinced it's not possible? you've obviously never tried or wanted to. so does that make it not possible? the whole thing's a theoretical discussion and it seems 340 guys don't like the possibilities. given the choice i'd use a 360 as they're almost as cheap as a 318 but that wasn't the original question was it?
 
$3000 ok let’s add it up. Good heads-$1200 average, no port work. But then you got those 7 to 1 pistons another $700 plus you gotta bore it out another $320 now you gotta balance $275 new bearings-rings $300 now a cam, good hyd roller $600, rockers $300, pushrods $80, springs for that big cam $200. Nice intake $350 carb $400 am I missing anything? Wow $4725 kinda out of you budget don’t ya think! You can’t just start adding parts it ALL ties together. No dick swinging 340 guy here, I live in a real world.
Knock $200 off for springs, they might be on the heads already. $4525 now
 
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Ceedawg said:
$3000 ok let’s add it up. Good heads-$1200 average, no port work. But then you got those 7 to 1 pistons another $700 plus you gotta bore it out another $320 now you gotta balance $275 new bearings-rings $300 now a cam, good hyd roller $600, rockers $300, pushrods $80, springs for that big cam $200. Nice intake $350 carb $400 am I missing anything? Wow $4725 kinda out of you budget don’t ya think! You can’t just start adding parts it ALL ties together. No dick swinging 340 guy here, I live in a real world.
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Things aren't cheap these days...Im going through it now with an overhaul of a 340. Only machining was the crank turned. I have just under 2 grand shelled out and I may pick up a set of aluminum heads, that will put me at 4 grand ish...till I get it in the car even more...
 
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I don't want to see any of yas...ANY OF YAS!.. converting a 318 to a 340...:lol:

download (1).jpg
 
Ceedawg said:
Well then I’ll turn my 340 5900 rpm. Both engines are capable of the same rpm since they have same crank. If bore size means nothing WHY do they notch the top of the bore around the valve? 22” less means a smaller pry bar to lift an object, nothing you can do to change that, WITH ALL THE OTHER PARTS BEING EQUAL.
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Didn't say bore size means nothing and some notch it's not a necessary mod for a 318 most don't. It's just doesn't suck especially with a rebuild overbore it's not that far from the so called magical 4" bore, LS guy's make 400-500 NA hp with 4.8l and 5.3l with a 3.78" bore, there basically cid wise close to 273 and 318 and if these engines came factory with something like edelbrock heads.

And yes a 340 and 318 are capable to turn the same rpm and if took out to the limits 318 obviously be behind but the 340 would need more cylinder head than the 318 to do so. So if use same cam and heads on both engines the 340 should peak at a lower rpm than the 318 will probably some ratio constant with there displacements.

But if you take a 340 vs 416 since they have the same bore the 340 will alway be able to turn enough rpm higher than the 416 to theoretically make up the displacement difference.

But were not talking about taking out to the limits here, I'd bet most street 340 peak somewhere between 5000-6000 rpm, so a 318 will need to peak 5350-6420 rpm about 7% higher to keep up and little more to beat. Not like the 318 gonna need radically different cam and heads to do so. But obviously there's more to it like Volumetric efficiency percentage VE%, and good way to know that is torque to cid ratio most engine will fall somewhere between 1-1.45:1 lbs-ft:cid. Most street guys are gonna make between 1.15-1.25:1 since there's a 9% difference which is more than the cid diffence there's a chance a well put together 318 can make as much or slightly more torque than the 340 but not usually, a 318 may or not need slightly different cam and heads for best VE%, a 318 will need more gear and stall though.
 
i'm betting most 340's peak around 5200 even though they are probably shifted much higher with 4 speeds.The stock 340's rev past 6000 easily
 
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Ceedawg said:
$3000 ok let’s add it up. Good heads-$1200 average, no port work. But then you got those 7 to 1 pistons another $700 plus you gotta bore it out another $320 now you gotta balance $275 new bearings-rings $300 now a cam, good hyd roller $600, rockers $300, pushrods $80, springs for that big cam $200. Nice intake $350 carb $400 am I missing anything? Wow $4725 kinda out of you budget don’t ya think! You can’t just start adding parts it ALL ties together. No dick swinging 340 guy here, I live in a real world.
Knock $200 off for springs, they might be on the heads already. $4525 now
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that'd come down to the desired street engine spec and cost of $3000 easy enough. lots of your quoted parts aren't what the build was about unless as some here would have you believe the 318 needs to be almost a 'race' motor to compete with the 340.
 
mygasser said:
that'd come down to the desired street engine spec and cost of $3000 easy enough. lots of your quoted parts aren't what the build was about unless as some here would have you believe the 318 needs to be almost a 'race' motor to compete with the 340.
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Depends on which year 318 vs which year 340 doesn't it? Are we taking about a race or a dyno pull. The OP staes "faster" I woul think that means a race. there are alot of variables, I would thing the cars would need to be near identical in weight, with compararble drivers, same gearing and trans etc.etc. But I dunno I am kind of stupid I suppose...:)
 
Ceedawg said:
$3000 ok let’s add it up. Good heads-$1200 average, no port work. But then you got those 7 to 1 pistons another $700 plus you gotta bore it out another $320 now you gotta balance $275 new bearings-rings $300 now a cam, good hyd roller $600, rockers $300, pushrods $80, springs for that big cam $200. Nice intake $350 carb $400 am I missing anything? Wow $4725 kinda out of you budget don’t ya think! You can’t just start adding parts it ALL ties together. No dick swinging 340 guy here, I live in a real world.
Knock $200 off for springs, they might be on the heads already. $4525 now
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wouldn't be my build at all.... I already have a 318 that will run with a production 340 and I only have 750 from carb to pan. AND, it still has the 1.74/1.5 318 heads..... Think if I threw another 2k into it, because the budget allows it.
 
Dartswinger70 said:
Depends on which year 318 vs which year 340 doesn't it? Are we taking about a race or a dyno pull. The OP staes "faster" I woul think that means a race. there are alot of variables, I would thing the cars would need to be near identical in weight, with compararble drivers, same gearing and trans etc.etc. But I dunno I am kind of stupid I suppose...:)
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no you're spot on, they'd need to be very similar spec which'd be hard to put together so a dyno session would probably be best. it is a theoretical discussion at the end of the day and i'm glad all the animosity and abuse seems to have died down. as i said previously we're all car guys and mopar guys at that. if we all liked/had the same thing it'd be pretty boring i think you'd agree, we may as well get new jelly mould/belly button cars. :thumbsup:
 
mygasser said:
no you're spot on, they'd need to be very similar spec which'd be hard to put together so a dyno session would probably be best. it is a theoretical discussion at the end of the day and i'm glad all the animosity and abuse seems to have died down. as i said previously we're all car guys and mopar guys at that. if we all liked/had the same thing it'd be pretty boring i think you'd agree, we may as well get new jelly mould/belly button cars. :thumbsup:
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If I would have posted 302 vs 351C on a 2500 dollar budget, it would have made sense and we'd have had a nice discussion.
 
mygasser said:
no you're spot on, they'd need to be very similar spec which'd be hard to put together so a dyno session would probably be best. it is a theoretical discussion at the end of the day and i'm glad all the animosity and abuse seems to have died down. as i said previously we're all car guys and mopar guys at that. if we all liked/had the same thing it'd be pretty boring i think you'd agree, we may as well get new jelly mould/belly button cars. :thumbsup:
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Yeah but the abuse can be fun...LOL! Just kidding. I agree on a dyno run and have suggested that folks watch :Nicks garage" 340 run, I beleive Nick got 320 Horse out of a 340 fairly stock I also believe. It is true they were underrated at 275 from the factory. I mislead the teener guys by saying "300 HP" I think If I were them Id be aiming for 320-325 HP out of a 318..I also seem to recall UTG and Lunar Outlaws 318 only pulling 230 or something so all UT's grinding and porting on the heads did nothing for that engine in terms of HP sain when they are rated at 235 stock from the factory. I mean in all reality the dyno runs on each engine are represented, out there on Youtube. It comes down to "what mods" will the 318 guys do to get a 320 HP dyno pull?
 
Dartswinger70 said:
Yeah but the abuse can be fun...LOL! Just kidding. I agree on a dyno run and have suggested that folks watch :Nicks garage" 340 run, I beleive Nick got 320 Horse out of a 340 fairly stock I also believe. It is true they were underrated at 275 from the factory. I mislead the teener guys by saying "300 HP" I think If I were them Id be aiming for 320-325 HP out of a 318..I also seem to recall UTG and Lunar Outlaws 318 only pulling 230 or something so all UT's grinding and porting on the heads did nothing for that engine in terms of HP sain when they are rated at 235 stock from the factory. I mean in all reality the dyno runs on each engine are represented, out there on Youtube. It comes down to "what mods" will the 318 guys do to get a 320 HP dyno pull?
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UTG seems to be somewhere between a bit of fun and a laughing stock really so his results can be taken with a pinch of salt. the 320/325 hp 318 ought to fairly easy with the $3000 budget though in reality.
 
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