W2 heads on a 318

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yellow rose said:
Even with a 2.02 valve you will see a power increase by notching the bores. Guys fit 2.02's in there and don't notch the bore, but it should be done.


Otherwise, no reason not to do it.
Click to expand...

I never notch anymore except when physical interference mandates. I think the crevice volume kills more power than any flow increase. J.Rob
 
318/360/340 will all be within 22 cid of each other if you run the same crank and the bore is big enough to make similar power as 340/360.

But I don't get why you'd pick a 318 to stroke if I was going to the expense of stroking I'd start with 340/360.

If I was to build a 273/318 it would cause I'd want that size of engine.
 
Sorry guys, I didnt see ANYWHERE that he wanted to stroke a 318 BUT did see where he wanted to stroke the 360.

I DID SEE that he wanted to mess around with a 318 with the W2 heads until the stroker got built. He said he wanted to see what he could do/get out of a 318.
 
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Well, if not a streeter, but a weekend bomber,
I tell you what, I buzz mine up to 7200 all the time, and the shrieking is awesome.
I used to get people chasing me down to know what was under the hood. And it never failed; the second I said 360, there faces fell, and all too often the very next question was why not a 340; those were real revers?
And I'm thinking; excuse me, did you not just here 5 seconds of screaming 367 with the tach pegged at 7200? Pegged at 7200. Get lost shmuk! But I don't say any of that.Later on I let it slip that, you know it's a 4.04 bore,same as a 340,but the crank has a 270 thousands stroke advantage. Two hundred and seventy thousands! You know that kindof makes it a 340 stroker? Suddenly they're interested again.
Point of story, I can almost hear that W2-headed Beast of yours ripping a streak, well past 7000, and yeah, it sounds awesome!
 
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Yea, 43 years later, people still get wrapped up on it being a 340 or it's garbage.
 
IMO
Say you had a 360/400 hp engine,and with all other things being equal;
For a 340 to achieve that would require about 1 size bigger cam. A teener might require 2 sizes bigger, or more.So yes it is possible to build similar hp and go racing. Since a given hp to weight traps at a given mph, everybody uses the same reargear. This can cause a real problem on the start line.
But on the street it's whole different ball-game. When it comes to small blocks, those 20 or so cubes become very valuable and/or very useful, cuz the vast majority of the time for a streeter is spent way below peak power, and usually considerably below peak torque as well. So this is where the small-cammed 360 shines,seeing as how it will make more low-speed torque.
And every time you upsize the cam, you need to upsize the gears, and/or the TC.So again, a 360 with say,a 268* does quite well with 3.55s. The 340 with a 275*cam will want 3.73s, and a teener with a 282* will want 3.91s. So again, it can be done. You just gotta deal with the issues that come with running big cams,big gears, and hi-stalls.
Where the 360 shines, is that it can cruise the hiway in more comfort, and sip less fuel,and since it doesn't need to rev as high, the engine should last longer too.And this, for a streeter is also an asset, cuz I for one, want my engine to last a really long time, cuz it cost me a really lotta money, and will cost me a really lotta more money to rebuild it, if it breaks.
So that is why, I started with a 360, even tho I had at least one of every size LA to chose from. I am a streeter first, and was a travelin' man when the combo went together, and to top it off nearly broke. So, for me the 360 hit the most bases.Well, that and the fact that it costs about the same to build any of the SBMs, so I thought; might as well start with the biggest.
But, I'm probably preaching to the choir, cuz I'm sure you all know this kindof stuff, and some probably know it waaay better, than do I.Perhaps most......
 
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AJ/FormS said:
IMO
Say you had a 360/400 hp engine,and with all other things being equal;
For a 340 to achieve that would require about 1 size bigger cam. A teener might require 2 sizes bigger, or more.So yes it is possible to build similar hp and go racing. Since a given hp to weight traps at a given mph, everybody uses the same reargear. This can cause a real problem on the start line.
But on the street it's whole different ball-game. When it comes to small blocks, those 20 or so cubes become very valuable and/or very useful, cuz the vast majority of the time for a streeter is spent way below peak power, and usually considerably below peak torque as well. So this is where the small-cammed 360 shines,seeing as how it will make more low-speed torque.
And every time you upsize the cam, you need to upsize the gears, and/or the TC.So again, a 360 with say,a 268* does quite well with 3.55s. The 340 with a 275*cam will want 3.73s, and a teener with a 282* will want 3.91s. So again, it can be done. You just gotta deal with the issues that come with running big cams,big gears, and hi-stalls.
Where the 360 shines, is that it can cruise the hiway in more comfort, and sip less fuel,and since it doesn't need to rev as high, the engine should last longer too.And this, for a streeter is also an asset, cuz I for one, want my engine to last a really long time, cuz it cost me a really lotta money, and will cost me a really lotta more money to rebuild it, if it breaks.
So that is why, I started with a 360, even tho I had at least one of every size LA to chose from. I am a streeter first, and was a travelin' man when the combo went together, and to top it off nearly broke. So, for me the 360 hit the most bases.Well, that and the fact that it costs about the same to build any of the SBMs, so I thought; might as well start with the biggest.
But, I'm probably preaching to the choir, cuz I'm sure you all know this kindof stuff, and some probably know it waaay better, than do I.Perhaps most......
Click to expand...

I don't think you need bigger cams in 318/340 to make same power as a 360. It's just the cam and head combo in a 318/340 is gonna move the powerband up in rpm compared to a 360. There for needing more gear which by the way cancels the torque advantage.

Since each can use the same strokes it's really only down to bore size that differs between them. If a 360 came with a 3.31 stroke it would of been a 333 cid engine.

Like said before there's only over 20 difference between them just like 383/400/440 if talking same stroke not the biggest difference.
 
AJ/FormS said:
IMO
Say you had a 360/400 hp engine,and with all other things being equal;
For a 340 to achieve that would require about 1 size bigger cam. A teener might require 2 sizes bigger, or more.So yes it is possible to build similar hp and go racing. Since a given hp to weight traps at a given mph, everybody uses the same reargear. This can cause a real problem on the start line.
But on the street it's whole different ball-game. When it comes to small blocks, those 20 or so cubes become very valuable and/or very useful, cuz the vast majority of the time for a streeter is spent way below peak power, and usually considerably below peak torque as well. So this is where the small-cammed 360 shines,seeing as how it will make more low-speed torque.
And every time you upsize the cam, you need to upsize the gears, and/or the TC.So again, a 360 with say,a 268* does quite well with 3.55s. The 340 with a 275*cam will want 3.73s, and a teener with a 282* will want 3.91s. So again, it can be done. You just gotta deal with the issues that come with running big cams,big gears, and hi-stalls.
Where the 360 shines, is that it can cruise the hiway in more comfort, and sip less fuel,and since it doesn't need to rev as high, the engine should last longer too.And this, for a streeter is also an asset, cuz I for one, want my engine to last a really long time, cuz it cost me a really lotta money, and will cost me a really lotta more money to rebuild it, if it breaks.
So that is why, I started with a 360, even tho I had at least one of every size LA to chose from. I am a streeter first, and was a travelin' man when the combo went together, and to top it off nearly broke. So, for me the 360 hit the most bases.Well, that and the fact that it costs about the same to build any of the SBMs, so I thought; might as well start with the biggest.

This is one of your best posts. J.Rob
But, I'm probably preaching to the choir, cuz I'm sure you all know this kindof stuff, and some probably know it waaay better, than do I.Perhaps most......
Click to expand...
 
So, lets see if I understand this right;
Say I take my 360/400hp to the track and it turns a certain mph. Then I go home, put a cam in it 2 sizes smaller. Then go back to the track, and turn the exact same mph, but now I can rev it 400 rpm lower?Or did I misread that.
Or maybe you are saying; pick a cam any cam, and stick it in a teener, go to the track, get a trapspeed.Go home swap that cam into a 360 all other things remaining equal, like I said, and 360 will now turn same trapspeed as teener, but at a lower rpm. Or did I misread that?
Or maybe the 360 in a 6000 pound truck outfitted exactly like a teener, will be the same sucked out as that teener, in that exact same truck,cuz its only 42 cubes different.
Or did I misread that?
So then at 1 hp per cid your teener is making 318 hp, and the 360 is making 360 hp. Its only 42 cubes and only 42 hp. Even if they both used the exact same cam,and all other things being equal;Stick them in identical chassis with identical gears, and ...... will they turn identical trapspeeds?
Or did I misread that?
I'm not sure what I read, but I'm confused.

Of course you have to spin the smaller engines faster, to get equivalent power. That's how the physics work, with all other things being equal. But to unlock those rpm, the cam has to keep pace. And since a particular trapspeed requires a particular rear gear,say to trap at 106 requires 4.56s or so and each of these engines, all producing 400hp,are stuck with this same gear, as I said;all other things being equal,each is stuck with the same starter gear.This is gonna be a bit of a problem for the teener, if the exact same stall is used in each engine.

But the whole gist of the post was towards the streeter, where small cams are the norm. Streeters almost shouldn't care about absolute power numbers.Those are just a function of rpm. Streeters should be concentrating on putting the torque exactly where it needs to be MPH-wise,for what they want to do, cuz streeters are pretty much a one-gear deal, and then optimizing their particular combo to show the best there.Then if gearing and stall are non-conducive to cruising the hiway, or to getting great fuel economy, which they might also be interested in,then the engine size needs to be up-sized so that the stall or gear can be reduced, and still end up with the same torque to the rear axles.
Look, I like to go hammer down at 35 mph and light up the 295s. In second gear with 3.55s, this is 2964rpm for me. Lets say I had just barely enough power to accomplish this. Just barely. Now pretend it was possible to reduce my bore size, without changing the Scr, to teener size. Now lets see what happens with 42 cubic inches less. Its only 42 cubes.
 
AJ/FormS said:
So, lets see if I understand this right;
Say I take my 360/400hp to the track and it turns a certain mph. Then I go home, put a cam in it 2 sizes smaller. Then go back to the track, and turn the exact same mph, but now I can rev it 400 rpm lower?Or did I misread that.
Or maybe you are saying; pick a cam any cam, and stick it in a teener, go to the track, get a trapspeed.Go home swap that cam into a 360 all other things remaining equal, like I said, and 360 will now turn same trapspeed as teener, but at a lower rpm. Or did I misread that?
Or maybe the 360 in a 6000 pound truck outfitted exactly like a teener, will be the same sucked out as that teener, in that exact same truck,cuz its only 42 cubes different.
Or did I misread that?
So then at 1 hp per cid your teener is making 318 hp, and the 360 is making 360 hp. Its only 42 cubes and only 42 hp. Even if they both used the exact same cam,and all other things being equal;Stick them in identical chassis with identical gears, and ...... will they turn identical trapspeeds?
Or did I misread that?
I'm not sure what I read, but I'm confused.

Of course you have to spin the smaller engines faster, to get equivalent power. That's how the physics work, with all other things being equal. But to unlock those rpm, the cam has to keep pace. And since a particular trapspeed requires a particular rear gear,say to trap at 106 requires 4.56s or so and each of these engines, all producing 400hp,are stuck with this same gear, as I said;all other things being equal,each is stuck with the same starter gear.This is gonna be a bit of a problem for the teener, if the exact same stall is used in each engine.

But the whole gist of the post was towards the streeter, where small cams are the norm. Streeters almost shouldn't care about absolute power numbers.Those are just a function of rpm. Streeters should be concentrating on putting the torque exactly where it needs to be MPH-wise,for what they want to do, cuz streeters are pretty much a one-gear deal, and then optimizing their particular combo to show the best there.Then if gearing and stall are non-conducive to cruising the hiway, or to getting great fuel economy, which they might also be interested in,then the engine size needs to be up-sized so that the stall or gear can be reduced, and still end up with the same torque to the rear axles.
Look, I like to go hammer down at 35 mph and light up the 295s. In second gear with 3.55s, this is 2964rpm for me. Lets say I had just barely enough power to accomplish this. Just barely. Now pretend it was possible to reduce my bore size, without changing the Scr, to teener size. Now lets see what happens with 42 cubic inches less. Its only 42 cubes.
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All valid points.
But, when you consider the geometry, a 318 at .030 is only .060 smaller on the bore than a 360. If the OP was putting W-2 heads on a 360, no one would be screaming he'd have to rev the piss out of it.


As a general rule, stroke dictates power at peak torque and bore dictates power at peak RPM. So the actual difference in RPM between a 318/340/360 is vary little. The OP won't have to rev the piss out of the make power.

In fact, I can tell you the stock W-2 port is pretty small for a 340 turning 8000 and making power up there, even with a tunnel ram. I fought a long time to make power over 7500 with W-2's on 340 inches. It's a *****. The port isn't that big. It certainly is too big for a 318 turning 6500.
 
Stock port W2 on a 340 or 360 block s fine at 6 - 6500 RPM's. Unless the cam is on the large side, your done making power by 6000 or 6500. ( Cam size dependent, among other things, but that's the general area rpm wise.)
 
ciamcoop said:
So I've wanted to build a stroker for awhile and have been collecting parts. I have a 73 360 block (thick casting-hopefully), econo w2 heads and single plane intake. I wanted to be in the 550 hp range. The stroker stuff with a forged crank and H beams isn't cheap though. I built a decent running 318 years ago, factory forged crank, 340 rods, flat tops, and 4v 360 heads. The 318 had the cam go flat so I tore it all down to go through it.
I have this crazy idea of trying to get more power on a budget lol. Is the 318 worth putting the w2 heads on it and maybe getting the compression ratio up around 10.5:1?
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Call me crazy but I read this as wanting 550hp on a stock-stroke teener, with W2s. How you gonna make that number without lottsa revs?
Or did I misread this too? Sux to be me then,lol
 
[email protected]/.630 add 1.6 rockers
Add N02 w/supercharger
LMAO

Did he not say that he is messing with a 318?
If not, my bad. A W2 318 for fun? Sure! Why not?

Why is AJ afraid of racing an engine up?!?!
Enquiring minds wanna know....
 
[email protected]/.630 add 1.6 rockers
Add N02 w/supercharger
LMAO
Click to expand...

I'd like to thank Rumble for a short winded answer that didn't answer his question but rather threw in more confusing information to help confuse and derail the OE posters plans via adding doubt and more routes to run that were never asked.
Way to go Rumble.
lmao

My 367 pulls to 7200 on a regular basis.It revs higher,but she's already quite far on the down-side of the curve.
 
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LMAO!
:rofl:
Woooooooooooooooooo!!!!!!
Ha ha ha ha ha

Now get back to work runching numbers! You will be called apon!
 
I honestly would not worry about all the drama. Bolt the damn w2 heads on to the 318.
The car will still cruise and idle. Sound mean as hell.
The small rpm differences be damned and peak hp crap. When cruising the roads who will notice?
When wanting Crack the throttle boil the tires and scare the small women and children while you grin ear to ear in pure acceleration fear.
Tell everyone they got smoked by a 318. Who cares what everyone thinks or wants to tell you.
If they ask if the car is numbers matching you can say yes (because the ownership matches the car in your name)

The flip side. Around here 318s are more plentiful then the 360s. Blow the 318 up or window the block... go get another 318 at the wreckers and they will be cheaper because nobody wants a 318
 
AJ/FormS said:
Call me crazy but I read this as wanting 550hp on a stock-stroke teener, with W2s. How you gonna make that number without lottsa revs?
Or did I misread this too? Sux to be me then,lol
Click to expand...

Sorry if I made it unclear. I was planning on 550ish with the 408. It'll take a bit to get that from the 318, but if it's possible why not. I'm not afraid to spin it to get there. I was mainly wondering if the w2s are worth even the thought of putting them on the 318. I guess enough compression, cam, and rpm they'll be fine.
 
dodgedifferent2 said:
I honestly would not worry about all the drama. Bolt the damn w2 heads on to the 318.
The car will still cruise and idle. Sound mean as hell.
The small rpm differences be damned and peak hp crap. When cruising the roads who will notice?
When wanting Crack the throttle boil the tires and scare the small women and children while you grin ear to ear in pure acceleration fear.
Tell everyone they got smoked by a 318. Who cares what everyone thinks or wants to tell you.
If they ask if the car is numbers matching you can say yes (because the ownership matches the car in your name)

The flip side. Around here 318s are more plentiful then the 360s. Blow the 318 up or window the block... go get another 318 at the wreckers and they will be cheaper because nobody wants a 318
Click to expand...

Yeah that's the plan.

What kind of power and revs will the 340 rods take? They've been double shot peened, sized, and bushed with arp bolts.
 
ciamcoop said:
Sorry if I made it unclear. I was planning on 550ish with the 408. It'll take a bit to get that from the 318, but if it's possible why not. I'm not afraid to spin it to get there. I was mainly wondering if the w2s are worth even the thought of putting them on the 318. I guess enough compression, cam, and rpm they'll be fine.
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ciamcoop said:
Yeah that's the plan.

What kind of power and revs will the 340 rods take? They've been double shot peened, sized, and bushed with arp bolts.
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Well ciamcoop, I'm not sure where the factory will give up. There pretty darn good.
As far as a W2 being a "Budget head," I'm not to sure that is an accurate route vs. Edelbrock heads. I got my 59*, W2's on a close out from Mancini racing. Under a grand delivered. At that price, they become arguably cost exceptable. There draw back, besides weight, is valve train. It is roughly double that of an LA heads.

IF, (stress point!) I can get the rest of the bare head done inexpensively, I'll have done well. Then porting on top of it is about the same cost BUT! I will be ahead with a higher performance ceiling over Ported Edelbrock heads. The W2's do not do better than Edelbrocks OOTB.

Now to get off my soap box, I'll say, if you already have them, then run them.
And don't look back. Just GO!
 
Yeah I picked em up a couple years ago from a guy who ran em for a season. They're like new, the ports look untouched and they're complete with valves, springs, rockers, etc. Guess I'll give em a shot.
 
AJ/FormS said:
So, lets see if I understand this right;
Say I take my 360/400hp to the track and it turns a certain mph. Then I go home, put a cam in it 2 sizes smaller. Then go back to the track, and turn the exact same mph, but now I can rev it 400 rpm lower?Or did I misread that.
Or maybe you are saying; pick a cam any cam, and stick it in a teener, go to the track, get a trapspeed.Go home swap that cam into a 360 all other things remaining equal, like I said, and 360 will now turn same trapspeed as teener, but at a lower rpm. Or did I misread that?
Or maybe the 360 in a 6000 pound truck outfitted exactly like a teener, will be the same sucked out as that teener, in that exact same truck,cuz its only 42 cubes different.
Or did I misread that?
So then at 1 hp per cid your teener is making 318 hp, and the 360 is making 360 hp. Its only 42 cubes and only 42 hp. Even if they both used the exact same cam,and all other things being equal;Stick them in identical chassis with identical gears, and ...... will they turn identical trapspeeds?
Or did I misread that?
I'm not sure what I read, but I'm confused.

Of course you have to spin the smaller engines faster, to get equivalent power. That's how the physics work, with all other things being equal. But to unlock those rpm, the cam has to keep pace. And since a particular trapspeed requires a particular rear gear,say to trap at 106 requires 4.56s or so and each of these engines, all producing 400hp,are stuck with this same gear, as I said;all other things being equal,each is stuck with the same starter gear.This is gonna be a bit of a problem for the teener, if the exact same stall is used in each engine.

But the whole gist of the post was towards the streeter, where small cams are the norm. Streeters almost shouldn't care about absolute power numbers.Those are just a function of rpm. Streeters should be concentrating on putting the torque exactly where it needs to be MPH-wise,for what they want to do, cuz streeters are pretty much a one-gear deal, and then optimizing their particular combo to show the best there.Then if gearing and stall are non-conducive to cruising the hiway, or to getting great fuel economy, which they might also be interested in,then the engine size needs to be up-sized so that the stall or gear can be reduced, and still end up with the same torque to the rear axles.
Look, I like to go hammer down at 35 mph and light up the 295s. In second gear with 3.55s, this is 2964rpm for me. Lets say I had just barely enough power to accomplish this. Just barely. Now pretend it was possible to reduce my bore size, without changing the Scr, to teener size. Now lets see what happens with 42 cubic inches less. Its only 42 cubes.
Click to expand...


My point was that I don't think you need 3 radically different cams to accomplish the same hp goal among the 3 different displacements.

All 3 will be similar in combination to make 400 hp just there idle/powerband and stall/gears will be quite different.

Not to over generalize but most serious street and street strip builds are gonna be in a narrow cam choice of around 275-285 for the most part doesn't matter if is a 273-512 cid.
It's basically the heads that decide the hp and the cid that decides the powerband.
 
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