We have some big name engine builders here and every one of them I've seen quote that larger valves increase power everywhere, so I wouldn't sweat that.
Budget cylinder heads for a 318
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We have some big name engine builders here and every one of them I've seen quote that larger valves increase power everywhere, so I wouldn't sweat that.
I think they would work fine.
Stock heads will get ya to the power level you want 300-325 hp,but you would be better off with aftermarket heads no point putting much money into stock heads. Plus you can get 300-325 hp with less cam or make more hp with similar cam you’d use with the stock heads. 9:1 Cr and a cam like xe262h or xe268h or similar with some gears and stall you’ll have a great streetable combo.
For street nasty the stock heads. The large port heads will loose throttle response and hp per second when going from 1/4 throttle to 1/2 or 3/4 throttle. The big port big valve heads yeah max numbers at wide open throttle. Drag race.
Really hard to beat factory heads for street nasty. But you may give up 15-20 hp depending on the combo. But have better throttle response with factory heads.
Really hard to beat factory heads for street nasty. But you may give up 15-20 hp depending on the combo. But have better throttle response with factory heads.
Since nothing is bought (car or engine), I suggest you continue your research and see what kind of budget it takes to obtain the car and engine you would like to have. See how much rust free Duster's run in price, heads of different types, and see how well it stacks up against your funds and then make decisions. Nothing wrong with coffee shop talk..... as for speedmaster heads, I did a home inspection on them and found nothing wrong, and they've been on my car close to 2 years issue free. I don't drive it much, though.
- P.S. - It's hard to say you are looking for "cheap, budget" and then quote your Dad saying "cheaper isn't always better". Little bit conflicting. Again, coffee shop talk. Do more searching in the for sale adds online
If your sticking with stock heads, 3.23’s, it’ll be a little harder to achieve your goal. Ported 318 heads do very well except that’s an iron head that is hard to find a ported to do the labor intensive work and a rebuild. The aluminum head becomes more ch more attractive with lighter weight and better flow as cast.
The Speed Master/Pro Comp heads are a good match. With 20cc’s more to the TF heads, the very important velocity through the head may start to become an issue. “MAY” being the key word. I’m becomes build dependent from this point on. And it just isn’t the engine, it is the whole drive train. 3./3’s do not release the power as quickly as 4.10’s and up. For that gear ratio, a quick stop light to light tire burner is a not really going to happen.
The aluminum cylinder head at the 170cc area and a cam duration around 220 to 228 area would be very good.
Get a good torque converter and up the compression ratio on the engine and you’ll be pretty good
The Speed Master/Pro Comp heads are a good match. With 20cc’s more to the TF heads, the very important velocity through the head may start to become an issue. “MAY” being the key word. I’m becomes build dependent from this point on. And it just isn’t the engine, it is the whole drive train. 3./3’s do not release the power as quickly as 4.10’s and up. For that gear ratio, a quick stop light to light tire burner is a not really going to happen.
The aluminum cylinder head at the 170cc area and a cam duration around 220 to 228 area would be very good.
Get a good torque converter and up the compression ratio on the engine and you’ll be pretty good
I think the conflicting words actually make sense. Just not in an expected way. Cheaper may not always be better so spending coin on a good item is better than spending twice (or more) on crap.
To that end, I don’t see a reason myself on a TF head expense at this level. Would it actually be better? I have seen dyno results that say YES! But I wonder how actually driving it would be. Maybe one day I’ll try something like this for fun.
Yeah I think it would be a good experiment on a 318. Get some factory magnum heads. Indy will bowl blend and port match for $250 per head then add $150 per head for a valve job. At that point it's sitting around $800 for the pair then add a couple hundred for springs and retainers. So $1000 into stock magnum heads maybe flow about 230-240 when done. Plus whatever you pay for the stock magnum heads. At the current price of speedmaster heads the price is fairly equal. And for a 300-350 hp 318 my personal choice is use factory rockers for magnum. Then whatever a person chooses for rockers on the speedmaster.
Then take the same engine and swap heads and dyno those babies! Be a good group project for the fabo crowd. That would get everyone's mind off of world events for a few moments and we would learn something to boot
I took your car wanted request out. You will need to start a wanted ad in the classified forums if you are looking for a car.
Click this and start up a want ad.
Cars and Mopar Parts Wanted
Cars and Mopar Parts Wanted
I thought about doing that when I posted above but if you lead a member directly, he will never know how to get there on his own. LOL
Dan the man
Well-Known Member
Dan the man
Well-Known Member
Iin
In the short time that I've been on this forum I'm already getting great support. I want to thank everybody for being understanding and helpful. I have to learn not to get the cart in front of the horse. Once a car is purchased, then I can move forward.
Dan the man
Well-Known Member
Just do yourself a favor and ignore the 318 haters....and there ARE a few even though they say they aren't. I mean heck, if you end up with a 340 or 360, great. Just don't let them talk you into discounting a 318, because they can be made to haul the mail. Somehow, I believe you already know that.
cookietruck
Well-Known Member
for a mild 318 i think a good set of magnum heads would be great.
small efficient combustion chamber, ports aren't too large, 1.6 ratio rockers.
small efficient combustion chamber, ports aren't too large, 1.6 ratio rockers.
@Dan the man
This is 100% true.
I’ll not argue that a bigger engine will do it better and easier, but there is nothing wrong with the smaller displacement engines. It just takes a little more. For your description of your target, the 318 is not going to have a problem.
Build what ya got and have fun.
ChargedDart75
Well-Known Member
My two cents, if you don't have an engine, get a Magnum. No matter what the displacement, they will make your power goal with ease, and with untouched heads to boot. If you already have an LA 318 (I couldn't gather that from your posts), run it man.
MOPAROFFICIAL
Oogliboogli
I think the AL speedmaster might be a bit much for your build and would be aimed more toward 3500-7500rpm type 318 builds. That would be more for a 400+ hp goal. Just my opinion.
The as cast port?
MOPAROFFICIAL
Oogliboogli
I think its 171-175cc? I'll have to check the pair here. Definitely 170's cc, 2.02 240'scfm
Ootb
Fwiw for comparison
Stock 318 124cc 175-180 cfm
340/360 head 155-160cc 197-228cfm
300-350hp goal? That's a 5500-5800rpm red line motor imo. Excess port volume only hurts this build.
That's how I'm looking at it
I've never understood how people lose it when you build and engine 42 cid smaller 360 vs 318 or even 20 cid smaller 360 vs 340 cause to them it's all about displacement but are ok with 80 cid deficit of a 360 compared to 440.
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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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.
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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