Budget cylinder heads for a 318

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AJ/FormS said:
And I will never understand how a budget build 318 morphs into big cam, big heads, big everything; but the stock pistons are still way down in the holes, requiring a hi-stall now, and usually gears. You guys crack me up. The only Thing still 318 is the displacement.
And like I said right in the beginning; on a tight budget, 325hp from a 318 is no small thing.
And now for the ultimate budget build;
since the hi-stall and gears are a given,
just install those right now and leave the engine alone; you will be amazed at how a 2800 and 3.91s can wake up your Duster.
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I agree with the stall and gear recommend, to me that's the main problem with smaller displacement you need deeper gears in a world where most want to run 3.55 at most, that's why my signature says "If your willing to gear it build it if not build a larger displacement, Or take solace in your compromises."

I don't know about "325hp out of a 318 ain't no small thing" guess depends what you mean, it's just cam 4bbl headers and a bump in cr away to me that's basic hot rodding build but yes stock 318 heads make you run a little larger cam than you'd need with even 1.88 360 heads, but it don't need big heads it's just dollar wise for most it's don't make sense to put money into stock heads of any kind why people are saying cheap aluminum heads not cause he needs them but there price so it's hard not to. And yes the OP should at least bump cr up to 9:1.
 
Dan the man said:
Hello everybody. I've been out of the car scene for awhile and I'd like to put together a 318 for fun. Not looking for a lot of power, something like 300-325 at the flywheel. Thanks
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Dan the man said:
I'm mainly looking for a fun car to drive and thought that a 318 could make decent power.
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Dan the man said:
It doesn't have to make 300 at the flywheel, I thought that would be a easy goal. If the car I find has a 318 already in it then that's good enough for me
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Dan the man said:
I do have a budget that I would like to stay at, but I don't want to have to re buy parts either
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273 said:
I don't know about "325hp out of a 318 ain't no small thing" guess depends what you mean
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"325hp out of a 318 ain't no small thing", means; principally, that it costs money. and with bolt-ons, as you know, the fun-factor is delayed..... unless you spend even more money now on the chassis.
 
AJ/FormS said:
"325hp out of a 318 ain't no small thing", means;
it costs money.
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325 hp 318 stock heads = 9:1 xe268h 4bbl headers
325 hp 360 stock heads = 9:1 xe256h 4bbl headers
Where the extra expense ?? beside 360 would have slightly cheaper pistons
Give them both the same heads and 318 would need less cam probably the same cam as the 360.

The OP still hasn't shown any desire to build a 360 why push it ??
would a 360 make slightly more power in a streetable powerband like idle-5200 rpm = yes
if built to make the same power would the 360 be slightly more streetable since = yes
will the 360 need less stall and gear = yes
at 325 hp does it matter all that much = no
if the OP is ok with this why can't you be ???
 
273 said:
325 hp 318 stock heads = 9:1 xe268h 4bbl headers
325 hp 360 stock heads = 9:1 xe256h 4bbl headers
Where the extra expense ?? beside 360 would have slightly cheaper pistons
Give them both the same heads and 318 would need less cam probably the same cam as the 360.

The OP still hasn't shown any desire to build a 360 why push it ??
would a 360 make slightly more power in a streetable powerband like idle-5200 rpm = yes
if built to make the same power would the 360 be slightly more streetable since = yes
will the 360 need less stall and gear = yes
at 325 hp does it matter all that much = no
if the OP is ok with this why can't you be ???
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He hates 318s :rofl:
 
273 said:
Not saying port volume velocity etc.. ain't important. But most are not gonna port and or go with the perfect port size flow etc.. for application especially for a smaller displacement. To me say were looking to get 350 hp out of stock 318 heads we'd be talking probably about at least 10:1 cr and 230 degree cam but with say speedmaster heads you would be able to do it with a lot less cam and cr and would be the more streetable package, to me that's why factory does it this way especially with modern engines like LS and hemi lots of cfm and small cams to make reasonable power, cause making power through head flow is more streetable than larger cams. To a 318 with speedmaster heads would be like starting with a 5.3l LS short block and why put money into 318 heads ?
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Just pretend I'm drinking a beer and rambling off my thoughts on it...cause I am.:D
I see your point. LS have a better port, its tall n skinny and velocity is abundant flowing 300's cfm vs sheistmaster.
I threw bait out there for the age old debate if when everyone used to say NOT to use 360 heads. "Kills the bottom end"
"kills the cyl pressure"
And so [email protected]@.300
Why am I picking .300 lift?
Because it's a real good indicator of how well the head will do on average and the valve spends a good amount of time there x2 compared to peak. Ok...
So...Now its let's put some sheistmaster 170's something cc ports on that do [email protected] as well... see?
Now I went with 175 on the j head.1.88 though I've seen a few more on 2.02 version. You get a 65cc chamber, or 68cc after minor seat blending and a new valve job.. that's stock 675 318@68cc
..but back to the comparison..The sheistmasters need a valve job to flow any better till .475- .500 lift. Yes they do 240's ootb..but lag below that and run with a regular iron head that is less port/more velocity.
Yes you can use'em, have the valve job fixed. Would it show a difference in the low end and over all snap of the throttle and any rpm..I believe it would.
Its basic.
2 ports...
One 15cc bigger than the factory designed port.
If both flow near the same, which makes more power?
Which would put you back in your seat more?
It's not always the cheaper route and not always the way to go..
But imo it's the truth. 160cc is already a jump from 125cc and I have ported a lot of 318 heads to 360 flow numbers and ridden in the cars that have'em. They amazingly pull hard @132-134cc port [email protected] [email protected] [email protected].
There is a close relation to rpm/cid with port volume when it comes to efficiency and torque.
 
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AJ/FormS said:
And I will never understand how a budget build 318 morphs into big cam, big heads, big everything; but the stock pistons are still way down in the holes, requiring a hi-stall now, and usually gears. You guys crack me up. The only Thing still 318 is the displacement.
And like I said right in the beginning; on a tight budget, 325hp from a 318 is no small thing.
And now for the ultimate budget build;
since the hi-stall and gears are a given,
just install those right now and leave the engine alone; you will be amazed at how a 2800 and 4.10s can wake up your Duster.

back in 74 the lowly lo-compression 4bbl 360 was rated 240 NET. What does that calculate to at the the crank? Would it be 275/285? What would it take to get that to 300? Ima thinking just headers, a free-flowing exhaust, and a decent tune. Next, just swap that pressure-killing 340 cam outta there, and install fresh cold air. Quick and easy 325hp; and cheap.. Not to mention the mountains of tire-shredding torque.
But I get that you 318-lovers might want to spend wheel-barrows of cash just to be able to say you did it with a 318, and so what if it cruises the hiway at 3200rpm, sucking copious amounts of wrong-grade gas. How is that helping the budget-conscious OP?

I mean, lets add this up; for a 318,
my plan is;
hi-stall and gears; 4.10s will get you 5000=60mph@10% slip, in second gear.

Your plan is
starting to look like; big-valve heads, moderate cam, 4bbl, plus the headers and exhaust, ................... but no pistons , so no cylinder pressure to speak of, so here we are back at; plus the hi-stall, plus the gears

But for a 360, my plan is to just drop it in with dual exhaust and drive it; 2bbl and all. The ultimate in a budget-friendly, smile-creating, tire-frying, satisfaction.

EDIT(here to bottom)
for you 318 lovers
Your love for all things 318 has made you budget-blind. The epitome of HotRodding has been from the beginning, and forever will remain, swapping in a bigger engine.
Nobody cares if your whatever displacement street-engine has whatever horsepower, the questions are; how far will it lay blackies? and how quick can it get to 50/60 mph? Does it haul the mail, and does it look good doing it?
I put it to you that a 110/120psi lo-po 318 with all the big-stuff bolted onto it, is still, at it's heart, a lo-po engine, and will remain so, until you take it apart and give it a new hi-pressure heart.

To the OP, a power number on paper, does not guarantee a smile at days end. To make power, principally, requires rpm, and rpm means a higher-rpm cam. With no other changes; a cam that operates at a higher rpm, does not do well at lower rpms. The higher it operates at, the more bottom end has to be sacrificed.
The 318 already starts life as a low pressure engine. For what is was born to do, it's meager pressure was mostly always adequate. But that same low-pressure, immediately make itself known, in the performance arena; showing up as a loss of power at low rpms. As a streeter, the vast majority of the time, your engine, especially with 3.23s, will be stuck trying to operate at those low rpms. In First gear with 3.23s and 27s makes the gearing to be 10mph per 1000 rpm so 3000=30mph, the end of the low-rpm window, and just getting into the midrange. If you put it into Second, the engine goes pretty dead.
Installing a 340 cam or one like it that has an Intake-closing angle of 64*, in an 8/1 318; the Wallace Calculator predicts a CCP of just 118 psi@900ft elevation. At such a low pressure, there will not be any tirespin, at least not both of them.
And so, with your tires married to the road, your engine IS STUCK in the lo-po mode to about 30 mph. The only bandaid is to install a convertor with higher rpm stall, to get you thru and past that stinking lo-po window.
Ok but, at the other end, with 3.23s, the stall is no longer of any concern. Say that big 268 cam power peaks at 5000 and you spin it to 5500. With 3.23s, that will be 50 mph at the top of First gear. The power may begin arriving at 3500, probably at the earliest, which is 35mph. So then, to be in the fun window, you gotta be in the zone of 35 to 50 mph; But you gotta get there first.. Outshifting First at 5500, the rpm will drop to 3250, and your engine is struggling to get back "Up on the cam". Which is now gonna take a lil longer.....
But anytime you are at under 30mph, your engine will forever be in lo-po mode, lower even than when it was stock. 117psi CCP is pretty stinking soft.
But hey, don't pay any attention to me; according to some, I am a 318 hater.
But from me, you at least get the truth. which is in part;
I strongly advise you, that since you are gonna need a hi-stall and gears, and a "posi" anyway, you might as well just do them first, and see what happens. The buy-in is a fraction of what the 318 lovers are throwing at you. and the ratio of dollars spent to satisfaction is, IMO, incredibly high.
FYI:
I ran a 2800 and 4.30s, behind my lo-po 318LA for one winter, but was so impressed, it was early July before I put the 367HO back in.
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He doesn't need 4.10 gears.

3.73
Regular old 2400 stall 'cut' convertor you can get anywhere for 200 bucks.
good vj 360 heads with .025 milled off to make them 67cc would work great.

Might not be the cheap route or best future potential, but it's the right size shoe for the foot.
Build it for what it's for... not for what it "might be"
 
I agree ... for a 318 use the old 302 castings 1.88 valves or so and some good pocket porting/bowl blending pretty hard to beat. Now when the magnum heads came out they are a out of the box performance head for a 318 and probably the best out of the box 318 head. And without a doubt the best performing factory 318's the factory ever put out. I'm not so sure that the 360 magnum is the best performing factory 360. But that's a different topic

Almost all small block mopar parts available are centered around a 340/360
 
jammied said:
I agree ... for a 318 use the old 302 castings 1.88 valves or so and some good pocket porting/bowl blending pretty hard to beat. Now when the magnum heads came out they are a out of the box performance head for a 318 and probably the best out of the box 318 head. And without a doubt the best performing factory 318's the factory ever put out. I'm not so sure that the 360 magnum is the best performing factory 360. But that's a different topic

Almost all small block mopar parts available are centered around a 340/360
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Problem with 302 heads not many are into porting so the 302 offers very little in performance gain over stock for most.

Plus 273/318 heads was designed for 273 in mind and not as a performance head. 273 head volume and cfm is in similar ratio with 273 displacement as a X is with a 340, a 318 is 47 cid bigger than a 273 and 22 cid smaller than a 340 less so after an overbore. A 1.88 360 heads would be closer to right if you kept volume and cfm ratio for the 318 the same as 273 and 340.

With and overbore a 318 is 12-17 cid less than a 340 and 0.060”-0.030” smaller than the so called magic 4” bore can see these aftermarket heads being that far off. Not needed for 300-325 hp but for the money can’t see a reason not to. But yes a 1.88 360 or a ported 1.88 302 or magnum heads would right inline with 300-350 hp 318.
 
273 said:
Problem with 302 heads not many are into porting so the 302 offers very little in performance gain over stock for most.

Plus 273/318 heads was designed for 273 in mind and not as a performance head. 273 head volume and cfm is in similar ratio with 273 displacement as a X is with a 340, a 318 is 47 cid bigger than a 273 and 22 cid smaller than a 340 less so after an overbore. A 1.88 360 heads would be closer to right if you kept volume and cfm ratio for the 318 the same as 273 and 340.

With and overbore a 318 is 12-17 cid less than a 340 and 0.060”-0.030” smaller than the so called magic 4” bore can see these aftermarket heads being that far off. Not needed for 300-325 hp but for the money can’t see a reason not to. But yes a 1.88 360 or a ported 1.88 302 or magnum heads would right inline with 300-350 hp 318.
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302 heads should make 325 hp without porting if rest the engine is built right....easy!
 
dirty white boy said:
302 heads should make 325 hp without porting if rest the engine is built right....easy!
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I agree, so can the head that come with the 318 he buys, unless he wants to build quench for a 300-325 hp motor there’s little point in them. A 1.88 360 will make 300-325 hp with a lot less cam than the stock 318 or 302 heads making for a more mild and streetable combo. Plus if you buy the right piston you still can build quench if one chooses with the 360 heads.
 
Indy does bowl work for $150 a head add $150 a head into a good 3 angle valve job from them. Or just get magnum heads and a good valve job. IMHO those are the best options for a 318. For a budget head. You would have to go with a step top piston with 360 heads. And that's fine other than adding rotating mass. Or get the edelbrock magnum heads. But with 2.02 valves in less than a 4" bore valve shrouding becomes a issue and it gets to a point of diminishing returns.

I think we should start a group build gather up donations and heads and send to holdner to do the dyno with same engine and cam just different heads.
 
AJ/FormS said:
"325hp out of a 318 ain't no small thing", means; principally, that it costs money. and with bolt-ons, as you know, the fun-factor is delayed..... unless you spend even more money now on the chassis.
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The 318 hater speaks again!
It’s the same cost to build minus pistons if so the route goes.
It doesn’t take as much cam as others have listed and think it does.
 
Dan the man said:
Why did my post lose 5 pages of information?
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They upgraded the server and something got corrupt somehow and they had to use a backup all the way back to the 27th. So everything after that is gone. Don't know if they can retrieve it or not.
 
RustyRatRod said:
They upgraded the server and something got corrupt somehow and they had to use a backup all the way back to the 27th. So everything after that is gone. Don't know if they can retrieve it or not.
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Thanks for explaining it to me
 
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