Yes. I'm a "fan" of all the LA/Mag small blocks. BB's too for that matter.
Today, dollar for dollar, is the 318 faster than the 340 ???
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Here's a good one a 68 383 vs 72 400. both are viable candidates for a hone and re-ring.
Sometimes cubic inches don't mean diddly. lol
now back to the 318 vs 340.
Sometimes cubic inches don't mean diddly. lol
now back to the 318 vs 340.
I personally love the 400. Huge bore, ready for a lot of extra cubes should one decide to change the crank, and still a Low Deck motor for better fitment. Again, I love the 383 too....
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If you have the money to build it the 400 would be my choice over the 383. However the 383 will walk the dog on the 400 in stock forum. And by this I mean a 68 or 69 383 versus a 72-73 400.
Here are some first hand facts of cars I owned that I'll share:
- '68 Plymouth Fury Police Package. 383 Commando factory dual exhaust all stock except the heads were redone with harden seats. 3.23 gears. Weight, 4150. Best ET as set up 15.19.
- '89 D150. 400 2bb, I added 4bbl and headers. Nothing fresh, ran as pulled. 727. 3.21 gears. Weight about 3850. Best ET 14.5 as it sat.
Ha Ha, that is not even close to being correct. Sorry.
Dave_J
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There can never be a direct factory compare of a low compression 2bbl 318 to a high compression 4bbl 340. Even the Police 318 4bbl was choked by huge chambered 360 heads and a piston half way down to china in the bore.
But if you took a 273 4bbl 10.25 CR and its horsepower to cube ratio and directly did the math of the 43 extra cubes it comes close to 273 HP for a 318. So put 10.25 CR pistons in a 318 block for a near 0 deck, put a 360 head with its 1.88 valves, a 340 resto cam, 4bbl intake, 625 CFM AFB and 5.9 magnum exhaust manifolds on it then it should pump out close to the same ratio.
But the 340 Cult will never agree.
But if you took a 273 4bbl 10.25 CR and its horsepower to cube ratio and directly did the math of the 43 extra cubes it comes close to 273 HP for a 318. So put 10.25 CR pistons in a 318 block for a near 0 deck, put a 360 head with its 1.88 valves, a 340 resto cam, 4bbl intake, 625 CFM AFB and 5.9 magnum exhaust manifolds on it then it should pump out close to the same ratio.
But the 340 Cult will never agree.
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I don't understand the 340 envy. I also don't understand the 318 can never be a High Performance build. They are just parts. Put your combination together, and run it. If you pick the right combination and have a clear goal in mind, you should be happy with the results, no matter what block you use.
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I have 340's, not for sale, a 318 magnum, just because I am curious and try different combinations and purposes. So far, my favorite is a 273 and a 4 speed. Go figure.
the thread kind of took a turn with "I'm a fan of" and therefore....
I have no special interest of either, as I'm a fan of both 318 and 340 and understand both. I thought it was truly a fair question considering todays prices, is the 318 a better choice if a guy only has 3k to buy and build his engine. Would he go faster at todays prices with the 318 vs 340 and their prices? Very fair question and to me, the 318 hands down wins this race. Doesn't mean I think the 318 is a "better" motor at all. I just think it means the money will go farther making hp vs the 340.
ain't nothing free, I'm taking the $ 3000.00 and building a roller 360.
I think the 360 is the winner on a tight budget and would pretty much be a pointless conversation. It's why I kept it out of the conversation. However, when looking at the grocery getter 318 vs the loved HP340, and every 340 was a HP version, it gets really interesting. Not a debate, but a conversation I thought was worth having.ain't nothing free, I'm taking the $ 3000.00 and building a roller 360.
ain't nothing free, if all I HAVE is a 318, I'm taking the $3000.00 and building me a 318.
no you wouldn't, you'd build a 383.....ain't nothing free, if all I HAVE is a 318, I'm taking the $3000.00 and building me a 318.
I think the problem comes down to use, a lot of people on here when it comes to built engines, they want an engine that makes a lot of racket and smoke the tires at will, and mainly drive through town above idle with a blip of speed once and a while, I’d rather have a slower but more balanced car, something that can handle bends ok with banging through the gears without worrying the backend will come around at any moment and have fun at reasonable speeds. Could see a 273/218 more inline with purpose.
The street is a very traction limited space. Faster at the track doesn’t always equate to the street especially at lower speed and short distances.
I'm going to end this debate now, dollar for dollar I'm stroking a 400 and smoking little brother. 
If we're not using the 318 model.
If we're not using the 318 model.
opinions vary.
Depending on gears and stall for each can make a big difference, most cars are under geared and stalled. Lots only run 3.23-3.55 which is gonna be the optimal max performance gear for less 1% for the other 99% of the other cars out there those gears are always gonna be better for larger engines.
To me that's the main reason to build larger displacement, most 360 probably should be running one full ratio lower than 3.23-3.55 and a 340 probably 1.25 lower.
What gets me is that almost nobody cares about the 90 cid and the 0.32”bore difference between a 440 and 360, but the 20-42 cid and 0.040-0.13” difference between 318/340/360 is a huge chasm. And that a 440 would be happier with 3.55 or less gears, less stall etc.. and yes you could build a 408 out of a 360 but you could build a 543 out of a 440 and I bet dollar for dollar you’d be better off with a 440. I know, I know size weight, price of performance.
360’s rule
33IMP
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