Making power out of the 318

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Get creative. I've bought cars, pulled them onto a rented/borrowed trailer and then stripped the engine/trans/driveline into the bed of my truck before hitting the metal recycler to dispose of the carcass all in one day. Some places want a car cut into peices first - couple buddies with sawzalls and grinders helps.
Never underestimate the value of spare parts. All the little things you get from a fully assembled engine add up quickly.
I did that with a rusty Dakota 2 summers ago.
Brought it home on a Thursday, rented a tow dolly from haul a mile away from where I bought the Dakota, (and a mile from work) went to work Friday /returned the dolly that morning on way to work,
and between my son and I we had everything I wanted off of it Saturday morning, towed it across the scale 2 miles from home with a nylon tow strap and... Done. .

i wanted the heads off of it (91, last of the LA 318s) the a500 trans, the '302 (actually '714 heads supposed to be identical to the '302casting, they are heart shaped closed chamber) the full gas tank, (at the time that full tank of gas was worth over 1/2 of the buy in price) a few interior parts for my 96 Dakota (like the heater controls, the radio and various trim)
I gave the guy his $200 asking price, tow dolly was around $60 for 24 hours, and when I took it across the scale 2 days later (can't make this up) I got 200.10 for the remains. And got what I wanted from it for free.... No, I "made" 10¢... And got my parts plus a free tank of gas.
 
he's got a slant with an automatic, he's starting from square 1 with the whole trans/converter situation.
I realize that. But if he went 360 magnum and got the 96-up flex plate he wouldn't need the weighted converter.

And am I the only one getting sick n tired of seeing an OP asking about a 318 and members at large here, answer the "318 questions" with "find a 360"?

Maybe he wants to use what he has on hand. Nothing wrong with that. Just help him build the best 318 he can. In this thread or any other of the gazillions of the ads asking about a 318 around here.


Especially in a case like this.... 15 yo kid. Were losing the younger generation fast enough as us. This is a 1st engine build. He ain't gonna know how to do alot of what's needed, between what has to happen in a machine shop, and plain simple inexperience.
Help him build the best 318 he can for now and if he wants to do a different engine later whatever engine that may be) deal with that later. Now if somehow the block is deemed junk-- cracked, bored to the max already, or some other way "unusable" now that might change the story and the suggestions.

Get him the experience of building an engine and building it right without cutting corners first and "building one up" later. Not saying at all it has to be a "stone stock" engine for his 1st go round/ as many upgrades can happen going thru the exact same motions with that same engine, by picking the right parts.
For now something he can have fun with while gaining some experience. A healthy 318 will be stronger than a stock/6 in the 1st place.

Whatever CID engine were talking about, at the power level he thinks he wants in something like an a body, well be reading about his crash and burn... I don't want to see that.
 
I realize that. But if he went 360 magnum and got the 96-up flex plate he wouldn't need the weighted converter.

And am I the only one getting sick n tired of seeing an OP asking about a 318 and members at large here, answer the "318 questions" with "find a 360"?

Maybe he wants to use what he has on hand. Nothing wrong with that. Just help him build the best 318 he can. In this thread or any other of the gazillions of the ads asking about a 318 around here.


Especially in a case like this.... 15 yo kid. Were losing the younger generation fast enough as us. This is a 1st engine build. He ain't gonna know how to do alot of what's needed, between what has to happen in a machine shop, and plain simple inexperience.
Help him build the best 318 he can for now and if he wants to do a different engine later whatever engine that may be) deal with that later. Now if somehow the block is deemed junk-- cracked, bored to the max already, or some other way "unusable" now that might change the story and the suggestions.

Get him the experience of building an engine and building it right without cutting corners first and "building one up" later. Not saying at all it has to be a "stone stock" engine for his 1st go round/ as many upgrades can happen going thru the exact same motions with that same engine, by picking the right parts.
For now something he can have fun with while gaining some experience. A healthy 318 will be stronger than a stock/6 in the 1st place.

Whatever CID engine were talking about, at the power level he thinks he wants in something like an a body, well be reading about his crash and burn... I don't want to see that.
yes, and no. i loves me some 318's but with his intended goal of 400hp that's just not feasible withing the constraints of the budget he's put forth. hence, 360.

if you read my other post, what it really hinges on is the 318 might be crap and starting out with a 360 could very well put him in a better position both financially and to meet his goal of 400hp. but again: we don't know. hence my suggestion to take it to the machine shop and find out, then make a battle plan from there.

i'm all about a 318 being great for a first build and it could turn into a fun little motor for not a lot of cash and a great experience... IF... the parts are viable; AND he resets his expectations HP wise.

play it out this way: say that 318 needs to go 40 over, there's 4~500 in pistons, and the crank needs turned 10/10, and the heads need a full tilt rebuild-- how much is that at the machine shop? a grand? so he's 1500 into a short block and heads that'll *maybe* support 300hp and he still needs a cam, timing chain, cover, intake, oil pan, oil pump and pick up.

fundamentally, when a 360 from the yard is $500 and you can get away with minimal or zero machine work then that's the play to make in this circumstance. yes, you'll still need some of those same parts: cam, oil pan, etx but the end goal of 400hp is substantially easier and cheaper to achieve.

anyway, at least the car's got discs on the front already.

thanks for coming to my ted talk.
 
It would be wise to build the 318, if it was a complete running motor but it's a basket case that is missing parts and will likely need some machine work. Since it's likely to be cheaper for him to buy a known OK motor than even assemble what he's got, it just makes sense.

The kid is still going to need a bunch more stuff to complete a V8 swap into a slant car, so keeping it thrifty has to be the main goal. Getting 400+ out of a 318 isn't hard, but getting there from where he is will be a steeper hill than grabbing a $500 Magnum and a busted $500 LA with an airgap or street dominator and headers or something on it already..

I mean, the right pistons to support his end goal will cost as much anyway.
 
The other thing the OP might also not know, due to still being a high schooler, is that 400 horses in an A body, can be a handful driving if not all the systems (brakes, suspension, power, fuel) are sound. If you do simple math, the car is at 3000 pounds with 400 HP it is 7.5 pounds per horse power to weight ratio (at 500 is 6 pounds) or a mid 12’s car at the drag strip in a steel soda can. Think riding a bike as a kid, you start on the small one and work your way up. 400 in an old car is not the same as 400 in a new car. One of my buddies has a lightly built 318 in a 67 fish, that car is quite the handful as the suspension was /6 and such, now the car is way better after time fixing her up…
 
Junk yard jewel talks about how to build a 400 horsepower 318. I don't know if this has already been mentioned, if it has I apologize for the repeat.
 
Junk yard jewel talks about how to build a 400 horsepower 318. I don't know if this has already been mentioned, if it has I apologize for the repeat.
yes it did, but the heads was ported so far thay cracked and leaked water into the ports... lots to read on here bout 302 heads and performance, got a set sale ya cheap of a 86 running 318 with only 86,000 miles!!

you want a easy 400 hp outta a 318, something close to this, with very lil machine work...
https://www.motortrend.com/how-to/mopp-0409-318-engine-build/
 
yes, and no. i loves me some 318's but with his intended goal of 400hp that's just not feasible withing the constraints of the budget he's put forth. hence, 360.

if you read my other post, what it really hinges on is the 318 might be crap and starting out with a 360 could very well put him in a better position both financially and to meet his goal of 400hp. but again: we don't know. hence my suggestion to take it to the machine shop and find out, then make a battle plan from there.

i'm all about a 318 being great for a first build and it could turn into a fun little motor for not a lot of cash and a great experience... IF... the parts are viable; AND he resets his expectations HP wise.

play it out this way: say that 318 needs to go 40 over, there's 4~500 in pistons, and the crank needs turned 10/10, and the heads need a full tilt rebuild-- how much is that at the machine shop? a grand? so he's 1500 into a short block and heads that'll *maybe* support 300hp and he still needs a cam, timing chain, cover, intake, oil pan, oil pump and pick up.

fundamentally, when a 360 from the yard is $500 and you can get away with minimal or zero machine work then that's the play to make in this circumstance. yes, you'll still need some of those same parts: cam, oil pan, etx but the end goal of 400hp is substantially easier and cheaper to achieve.

anyway, at least the car's got discs on the front already.

thanks for coming to my ted talk.
Thank you for the ted talk lol i wish i had the money to build that 318 but your right the 360 mag is where it is at i can pick one up running for $400 and put new rings and bearing's in The bottom end as a somewhat cheap insurance and a good cam etc and make good hp for way less money
 
yes it did, but the heads was ported so far thay cracked and leaked water into the ports... lots to read on here bout 302 heads and performance, got a set sale ya cheap of a 86 running 318 with only 86,000 miles!!

you want a easy 400 hp outta a 318, something close to this, with very lil machine work...
https://www.motortrend.com/how-to/mopp-0409-318-engine-build/
Are 302 heads a true decent budget cylinder head for a 318? I'm between buying a set of 302's or a set of speedmaster cylinder heads.
 
Are 302 heads a true decent budget cylinder head for a 318? I'm between buying a set of 302's or a set of speedmaster cylinder heads.
The speedmasters are good but you need to have them gone tru by a shop and get new springs the stock ones like to break thats what my uncle said he has a 78 diplomat with a mag 360 makes 400 he is running stock heads but when he was looking into the speed masters that what he read
 
you want a easy 400 hp outta a 318, something close to this, with very lil machine work...
https://www.motortrend.com/how-to/mopp-0409-318-engine-build/
i've built this engine. yes, it makes 400hp but just barely and if you look at the dyno results you'll notice that it has a narrow, peaky powerband.

it's fun, but that wears off quickly if you've got a 4spd because you're always stirring the pot looking for that sweet spot of power. it makes less power but is A LOT more driveable and well mannered with a dual plane and a more reasonable carb.

anyway, it's not as cake of a build as they make it out to be. a ton of little details that need special attention. and the machine work must be *on point*. and without headers, this probably makes 370/340.

nice lopey idle tho.
 
Are 302 heads a true decent budget cylinder head for a 318? I'm between buying a set of 302's or a set of speedmaster cylinder heads.
to make any power thay need porting, alot!!!! and thay need bigger valves as well! thay good head for a mild 318 build driver or a truck... buy time you port and add big valves you can buy the speedmasters...
 
i've built this engine. yes, it makes 400hp but just barely and if you look at the dyno results you'll notice that it has a narrow, peaky powerband.

it's fun, but that wears off quickly if you've got a 4spd because you're always stirring the pot looking for that sweet spot of power. it makes less power but is A LOT more driveable and well mannered with a dual plane and a more reasonable carb.

anyway, it's not as cake of a build as they make it out to be. a ton of little details that need special attention. and the machine work must be *on point*. and without headers, this probably makes 370/340.

nice lopey idle tho.
think a different cam might could spread that power band you reckon??
 
Are 302 heads a true decent budget cylinder head for a 318? I'm between buying a set of 302's or a set of speedmaster cylinder heads.
they can be depending on what your combo is and what expectations you have power wise. 300-ish HP or less, yeah. why not.

speedmasters are fine, but should be inspected before being run. both PBR and 318WR have write ups about their findings. to the stacks with ye! research beckons!
 
think a different cam might could spread that power band you reckon??
maybe? i mean, it'd be interesting to see an analysis on computer modeling/software of what could be. i forget what the the finer specs of the cam were but if i had to do it again i'd probably spec something out instead of grabbing an off the shelf grind.

but i think it's mainly the architecture of the motor in that you really gotta spin those small bores up to move enough air, and that comes at loss to low and midrange which is only magnified by the already anemic lower rpm numbers.

if you were specifically building a car to go jackass around in and you had most of this stuff laying around it could be real fun (and probably make you a nice bundle of money)-- especially with some steep gears and a 4spd or a bunch of stall.
 
maybe? i mean, it'd be interesting to see an analysis on computer modeling/software of what could be. i forget what the the finer specs of the cam were but if i had to do it again i'd probably spec something out instead of grabbing an off the shelf grind.

but i think it's mainly the architecture of the motor in that you really gotta spin those small bores up to move enough air, and that comes at loss to low and midrange which is only magnified by the already anemic lower rpm numbers.

if you were specifically building a car to go jackass around in and you had most of this stuff laying around it could be real fun (and probably make you a nice bundle of money)-- especially with some steep gears and a 4spd or a bunch of stall.
a good port job, the right cam an converter, light car deep gears,..yup yup yup....
 
Thank you for the ted talk lol i wish i had the money to build that 318 but your right the 360 mag is where it is at i can pick one up running for $400 and put new rings and bearing's in The bottom end as a somewhat cheap insurance and a good cam etc and make good hp for way less money
I rebuilt my first engine last year and wanted it to be the least costly possible. I just wanted a reliable street rumbler engine. I went with a 318 magnum (same things apply to a 360 magnum except engine balancing which impacts flexplate/torque converter and harmonic balancer) I had my block and heads machined and went .030 over. Here's the rest of what I did and found success in spunky little engine that feels like A LOT more power over the slant 6 it replaced in my 67 Dart : You can send the original cam out to Oregon Cam Grinding and have a new profile ground for under $300 including shipping back and forth. They have many hydraulic roller profiles available. I did the #1280 on a 110 lobe sep (212/[email protected] .485/.506). While in there get some stock replacement lifters (or don't worry about it and just put the old ones back in the same holes for good measure). Replace the head gaskets with the .028 set from Mr. Gasket for a tick more compression. This will give you experience in measuring and ordering new longer pushrods since the cam base circle is reduced by grinding and the heads are slightly closer to the deck. I splurged on a set of nice Trend pushrods. Get a Hughes 1199 valve spring kit and install some new valve stem seals while you're in there. I dressed mine out in LA engine front dress and a 360 car oil pan, taking cues from Magnumswap.com. I used an Edelbrock 7577 intake and a 1405 carb. I sourced a complete stock and electronic ignition with curved distributor on FABO from @halifaxhops. I bought some 2nd hand hedman headers. Without any machining you can do all of this for less than $2700.00 and that's if you buy it all new. I bought my carb, intake, headers, timing cover, pulleys here on FABO and saved some money. You will be surprised how costs of the little parts and gaskets add up quickly. I think you would be totally shocked at the power increase and the rewarding feeling of doing these simple " hot rodding" upgrades.
 
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so i recently got and 1973 small block 318 i am very new to mopar and was wondering what to do to the 318 i have every thing but the pistons the guy that i got it off of droped one and cracked it, i also have 360 heads that i would like to put on i am thinking about putting kb 167 pistons (0.40 over) in it, stock crank, stock rods and a rad cam with a lot of lope because i am a stupid kid, and stock 360 heads and then some kind of single plane intake and then a 750 double pumper i am really on a tight budget. is all of this possible or unrealistic.
I didn’t want a lot of extra but just wanted a lot of bling.
Here’s a stock 318 I built with intake, 4Bbl and serpentine kit.
Before and after.

165C6013-873B-48F6-9BE3-4CB55D08D04F.jpeg


6045FEC7-ABE4-45D1-A4E7-E35537AFDFB2.jpeg
 
I have 1 problem with the speed master heads idea. And it's a huge one. Aren't they made in China??? I'm tired of this.
When I built my last engine (which happened to be a/6) I bought a good majority of my parts here and there from eBay, new parts but "dusty boxes"
partly because I got them at a great price but partly to avoid the China deal as much as possible. And it was actually easier to find much of what I needed for a better price. Much of what was needed I couldn't even find locally.
It does take some looking around there though. What you might need, you might not see today, but it might pop up tomorrow. And the first example of what you are after you can't buy. Put it on the watch list so you can find it later if needed.
I've seen too many times where the 1st one that popped up (of whatever you were looking for) might be $150. The next page down that same exact thing is listed for $40.
For the cam I sent my original one to Oregon for a regrind. As well as bought my lifters from and my valves too (SI brand oversized)

Also, I do all I can with stuff I already have.
 
so i recently got and 1973 small block 318 i am very new to mopar and was wondering what to do to the 318 i have every thing but the pistons the guy that i got it off of droped one and cracked it, i also have 360 heads that i would like to put on i am thinking about putting kb 167 pistons (0.40 over) in it, stock crank, stock rods and a rad cam with a lot of lope because i am a stupid kid, and stock 360 heads and then some kind of single plane intake and then a 750 double pumper i am really on a tight budget. is all of this possible or unrealistic.
As an old fart, I may have learned a couple of things over the years.
What vehicle will this be installed into and what is your intended use. Sit back and have a real hard and honest talk to yourself on that.
You say you have most of the parts to put it back together but only 7 pistons. With your comment on "extremely tight budget" in mind, find the manufacturer of the pistons you have and purchase one replacement.
Being a youth you need to not go out of your way to find attention from those in uniforms. With that in mind, a quiet exhaust is required. That real lopey cam for street with power assist brakes even with a cannister is not optimal. You will be much better served with an optimized cam. By that a narrower LSA and less duration to keep overlap down will let you keep the vacuum assist brakes without issue. To select the cam LSA, either watch David Vizard's Powertec 10 videos. He has one on What the Cam Companies Still Get Wrong, and another that explains his 128 formula. This is also explained in his book How to Build Horsepower. Another excellent book is Porting and Flow Testing Cylinder Heads.
Uncle Tony of Uncle Tony's Garage presented a project to DV on 318 build using a 2V carb and looking to make over 300 HP. Charley Servidono has been porting the heads and intake for it. DV did a few videos on lightening and race prepping the connecting rods. This is applicable to street driving and will increase reliability at minimal cost but a bunch of time.
Another weight loss area is valves. The LA 360 valves are heavy due to a large part, large diameter valve stems. You could use Magnum valves with 1.88" intake valves and 5/16" stems. Another alternative is Chev LS valves. 1.9" intake and 1.55" or 1.625" exhaust. Because millions of these engines have been manufactured the parts are fairly inexpensive. You could go to a Pick'n Pull when they have a head sale and just pull the heads off a low mileage 5.3l or 6.0l and take the valves, springs, retainers and keepers from them. Sell the castings. These engines are easy on their valves, so the head machinist should be able to do a light touch up of the valves. These have 8mm stems. You get 5/16" bronze guides installed and honed to fit the valve stems.
For the cam LSA: 128 - (displacement of one cylinder ÷ ( int valve dia × 0.91)).
318 at 0.030" oversize is 3.94"
3.94 × 3.94 × .7854 × 3.31 = 40.36
Using the LS 1.9 Intake
1.9 × 0.91 = 1.729
40.36 ÷ 1.729 = 23.3. Just round to 23.
128 - 23 = 105° LSA indicated
It is probably hard to find a cam grinder that would grind someone they do not know a cam with that tight a LSA, especially if you are pushing for long duration. You should be able to get a cam ground on 106° to 108° LSA with 220° to 225° @0.050 lift. For lift you should be looking at 0.500" to 0.525". This would be similar to a Comp Cams Thumper cam and deliver the lope you desire. With 10:1 or 10.5:1 compression you should have a strong running engine.
For mostly street driving, IMHO, you will be better served with an Edelbrock Performer Airgap manifold. Stay away from the knockoffs as QC is showing up as problematic. For a carb I would choose an Edelbrock AVS2 650 or 750. If you want a Holley, the vacuum secondary 750 or a 650 will also work well. Double pumpers were designed as race carbs to give throttle response with long cams. The offset is that extra shot of fuel can be a detriment on the street. Yes it can be tuned to function properly, but you need to know what you are doing.
Think long and hard before doing anything and create a whole car plan. You build power into the engine you need to build power in the brakes (heavier duty) and suspension before you drop the razoo engine in. Once you get the plan finalized, with help from the geezers in the local car club, stick to it. Changing your mind half way through gets expensive quick.
Just a FYI, my neighbor's kid got his GDL about 01 Sept 2023. The G is graduated, so much of any infractions in the first year and they lose it for a while and have to go through the whole licensing procedure again. I see the truck he was driving parked at his mother's and had heard he had been stopped for speeding and seatbelt infractions. This leads me to think he is taking shank's pony about town. He is under the influence of his idiot cousins and their rectum attitudes. This has brought police interest and once they are watching they will not let much slide.
 
yeah. dual plane.



for sure dual plane.

Ahh i hate being there i want to get out and go to trade school for welding the only thing that is fun is girls, football and auto shop
Watch out for the girls part. That can get real expensive way too quickly.
Like the army said in WW2 health film, treat your ***** like your rifle, keep it dry.
 
Thank you for the ted talk lol i wish i had the money to build that 318 but your right the 360 mag is where it is at i can pick one up running for $400 and put new rings and bearing's in The bottom end as a somewhat cheap insurance and a good cam etc and make good hp for way less money

I would avoid replacing the rings. It would be good to check a few main bearing but if they're good then leave them. A mistake while doing an at home hone, especially if you're inexperienced, and you're right back to needing machine shop services and possibly pistons. Magnums were efi and rarely have enough internal wear to worry about.

Get the mag, get an intake (Magnum airgap), get headers, and then figure out a cam. Keep the old cam and lifters and stuff from the Magnum for the future since they're rollers, but finding a mild roller cam isn't the easiest unless maybe you have one ground but I've no experience with Magnum cams, others might chime in.

Save the ring and bearing money for a transmission rebuild kit since you're much more likely to need to do that than put rings in a Magnum.
 
Ok why do you say flat tops not a dome piston? because some of the forms i have read say the domes are the best for the 318 i am just curious
Flat top pistons have the best flame propagation. The dome can get in the way of the flame propagation. Have you ever tried pouring a bit of gasoline in a line on a driveway or sidewalk. Make certain nothing that could catch fire is close. Cap your gasoline can and put about 10 feet away. Then light one end of the spill. You will see how the gasoline burn spreads. In the cylinder is quite similar, it is a progressive burn, not an explosion. If it explodes - detonation, bad and expensive things follow.
The decision between flat top or dome is reliant on the cylinder heads available or chosen. Open chamber heads do not promote cylinder mixture motion which aids a quick and efficient burn. If you watch DV's porting videos, he shows how to promote swirl, which is mixture motion. Those factory open chamber heads are prone to dead mixture motion which allows detonation.
Quench heads have a flat area that is level with the head gasket surface. Generally you want about 0.040" clearance between the piston top and that quench area. As the piston approaches TDC it squeezes the air/fuel mixture out of there at high speed, generating mixture motion and a quick burn. A thought, look up Somender Singh "groove technology". A local here uses it on his sled engines and swears by it.
With some heads you just need to use a dome piston, but keeping it down to say 0.100" is best for flame travel. Considering you can still drive with the leaning tower of power it may be wise to keep your eyes out for a good set of aluminium.heads with tight combustion chambers of about 60cc, and then chose the pistons. Remember, form a plan first. Getting good heads with small combustion chambers is part of the planning. Used parts are out there and someone on here may have what you need. Swap meets will be coming up soon. Get there EARLY as the good stuff gets snapped up early.
I hope that helps some.
 
I really like your thinking i think i will use what i have and use some kind of KB piston but i am a little lost on that should i use 399s or 167s if you dont know thats ok i will dig deeper into the internet
Look for flat top pistons that will put the piston top level with the deck surface. That enables good flame travel across the piston and will work with almost all heads. Piston to valve clearance is the catch phase on that. Big valves won't clear all piston valve reliefs. The valve reliefs can be enlarged later if required, but best to account for that up front.
Same goes for relief depth, with a milder cam you would have lots of clearance at the expense of a bit of compression. DV also speaks about piston porting. This involves dressing the sharp corners at the edge of the relief and also cutting it back to allow the incoming air to easily flow into the cylinder while the head is still close to TDC. Attention to details add up. The piston porting is dealt with in his BBC book.
 
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