What do you think about this 318 guys.

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Icetech said:
Yeah, i have had people tell me not to do 426 but no one with a good reason why not.. Everyone thinks 408 over 390 is a MASSIVE jump in power, but 408 to 426 doesn't matter... although it's pretty much the same price to do.
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Because you will be horribly induction limited. All you’ll do is move the TQ and HP curves down.

Unless you have some very high end heads (and that’s not W2-5 heads…maybe a W7 or the big Indy head and even then the cross section is on the small side to make any power at other than John Deere RPM) you‘ll strangle the engine.

You could do sub 400 inches, shift at 7200 and drag a 426 by the balls anywhere you want to go.
 
nah I got it... right away I'm thinking "wouldn't the early 340 piston dome hit the closed chamber "LOL! :)

hey it might work with the later 340 right? :)

Ill never stop getting a kick out of the 318 guys,

the ones who have never tore down a 340 and laid the internals out on a bench

its like they don't know what they are talking about the UTG 318s are just as good as a 340 crowd LOL! :)
 
Rat Bastid said:
Because you will be horribly induction limited. All you’ll do is move the TQ and HP curves down.

Unless you have some very high end heads (and that’s not W2-5 heads…maybe a W7 or the big Indy head and even then the cross section is on the small side to make any power at other than John Deere RPM) you‘ll strangle the engine.

You could do sub 400 inches, shift at 7200 and drag a 426 by the balls anywhere you want to go.
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I like to keep under 6500-7k which is why i was thinking torque.. i will prolly end up making my 318 a 390 anyway so it's moot :)
 
Icetech said:
I like to keep under 6500-7k which is why i was thinking torque.. i will prolly end up making my 318 a 390 anyway so it's moot :)
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I‘ll run some numbers in a bit on a 426 that will make peak TQ at say 5200 which should get you a shift point of 6500ish.

I think youll be surprised by the size of cam you’ll need.
 
Rat Bastid said:
I‘ll run some numbers in a bit on a 426 that will make peak TQ at say 5200 which should get you a shift point of 6500ish.

I think youll be surprised by the size of cam you’ll need.
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This is all next year stuff.. so no biggy right now, just bullshittin. And i am more about reliable than peak power.. no point in getting 45more hp if it ends up in a oily pile on the ground
 
Icetech said:
This is all next year stuff.. so no biggy right now, just bullshittin. And i am more about reliable than peak power.. no point in getting 45more hp if it ends up in a oily pile on the ground
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My quick math says you’d need 272 at .050 just to get peak torque at 5500. And that was at 11.5:1 compression. If the compression is higher you’d need still more at .050 to keep the TQ peak at about 5500.
 
Rat Bastid said:
My quick math says you’d need 272 at .050 just to get peak torque at 5500. And that was at 11.5:1 compression. If the compression is higher you’d need still more at .050 to keep the TQ peak at about 5500.
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Interesting, What math? Would you be so kind to explain a little?
 
273 said:
Interesting, What math? Would you be so kind to explain a little?
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Hey Rat Bastard teach these kids how we master engine building 101.

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Icetech said:
First step... look up Vizards cam formula....
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Already read most his books and articles, his youtube channel is a little hard to watchs he's dry and rambles, needs to be scripted.

I don't think David Vizard is the end all be all, last word when it comes to performance but at least unlike most he gets into reasonable details of his theories. And has cohesive theory.
 
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273 said:
Interesting, What math? Would you be so kind to explain a little?
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If you go to speedtalk.com and see if you can get a copy of “The Horsepower Chain” because there is great math in there for about everything.

So far, all the equations in that book have proven to be very accurate.

Last time I checked the book was 60 bucks or something. It ain’t cheap.


EDIT: as of 11/07/2022 that book is 80 bucks shipped. Worth every penny IMHO.
 
Rat Bastid said:
Because you will be horribly induction limited. All you’ll do is move the TQ and HP curves down.

Unless you have some very high end heads (and that’s not W2-5 heads…maybe a W7 or the big Indy head and even then the cross section is on the small side to make any power at other than John Deere RPM) you‘ll strangle the engine.

You could do sub 400 inches, shift at 7200 and drag a 426 by the balls anywhere you want to go.
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That's why i personally like the 3.79 stroke type deals...
 
Rat Bastid said:
Because you will be horribly induction limited. All you’ll do is move the TQ and HP curves down.
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It seems that's the main reason lot's build 402+ sb, is to get 450-550 hp at rpm that they feel is more friendly. Seems most only want to run 3.55 gears at best.
Rat Bastid said:
Unless you have some very high end heads (and that’s not W2-5 heads…maybe a W7 or the big Indy head and even then the cross section is on the small side to make any power at other than John Deere RPM) you‘ll strangle the engine.

You could do sub 400 inches, shift at 7200 and drag a 426 by the balls anywhere you want to go.
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Makes sense in take no prisoner build.
 
there's tons of magnum 318/360 motors rolling around the yards out here in socal. it's just that you have to go and pull them. i'm not sure what a short block would run ya, but a complete is about $700 minus the electrics and some tat.

**** i have one that got yanked out of a running 1500 just cooling it on the shop floor. so they're out there. they're just not 12 pack and 5 twenties pricing anymore.
 
I kinda pulled the plug a little early around here. I was getting LA blocks and cranks for 50-75.00 around here bare and taken apart. When I bought my R3 block and had around 10-13 blocks I quit buying them. I never see anything under 100.00 now and if I do it’s for just the block. I rarely run a stock crank now but I’m pretty low on stock.
 
Dartswinger70 said:
whats the point of the 318 block is it the shared stroke with the 340? I believe its a 3.91 bore that cant be taken to 4.0 correct? The only advantage I see is traditionally a 318 was laying around free or cheap i bought a LA 318 with a 904 bolted to it with every thing from carb to linkage to exhaust manifolds for $40 delivered that was 20 years ago though.
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I don't get why 4" bore is some magical number.. a 318 can be 3.970 and i believe 4 if sonic checked and you like cracked walls :) But you are telling me .090 matters that much?
 
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Icetech said:
I don't get why 4" bore is some magical number.. a 318 can be 3.970 and i believe 4 if sonic checked and you like cracked walls :) But you are telling me .090 matters that much?
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My point always is a 318 isn't a 340 and cant be made into one there are similarities in and around the crank stroke etc but why go to the lengths to make it into something its not the chrysler engineers didn't even waste their time on a 318. They redesigned it to be a 340. The 318 is or was cheap they were laying around every where other than that dumping money into them negates what they really are a cheap reliable v-8 I get into this discussion all the time and all it is is internet arguing next youll say "but 340s aren't around" I say yes they are they will cost you just for a core...if someone really wants a 340 they still can be had 360s also I see people who cant give away 318s on here occasionally thw 273 is even worse if these engines are so great why is it noone will give a guy 100 bucks for one? There was a 318 in CT on here once and the guy was like "come and get it" i thought about it as Im about 5 hours away but themn i thought " what the hella m I going to do with it it wiill sit..." the 318 thing is internet bullshit I really think and thats my opinion. Uncle Tony perpetuated it and his nut sniffers really beat that drum.
 
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