Just curious, why would you go with magnum heads over the 302's it's already got?
Cheaper than dirt 318 build
- Thread starter lud
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Magnum heads will have bigger valves and ports, and will flow more than the 302's. I always hate giving up the rocker shafts, but something gives, right? lol Also, unless you drill them for the LA bolt pattern intake, you are kind of stuck with the air gap... unless you are really patient for the old M1 dual plane. But i guess I'd just take the entire magnum engine.
You also gain 1.6:1 ratio rockers in the switch.
if he just put a Chinese air gap on a 5.2, he'd just about have his 300 hp (gross). They already come with a truck oil pan.... I'm not sure what the situation is on the pilot of the magnum crank. I know many were manuals, so maybe they do both ???? ?? ?
it takes a fair size cam to make 300 hp with stock 302's and magnum heads make about 300hp with stock cam.
here's a 230 cam with magnum heads and 10:1 cr makes 400 hp
318 Engine Build - A Parts Book 400HP 318 - Mopar Muscle Magazine
and here's a 218 cam stock 318 heads 8.?:1 makes 282 hp
318 Long Block Bolt Ons - Tech Articles - Mopar Muscle Magazine
here's a stock 5.9l magnum making 311-327 hp depending on exhaust.
Installing Exhaust Headers Into 300hp Crate Engine - Mopar Muscle Magazine
318 Engine Build - A Parts Book 400HP 318 - Mopar Muscle Magazine
and here's a 218 cam stock 318 heads 8.?:1 makes 282 hp
318 Long Block Bolt Ons - Tech Articles - Mopar Muscle Magazine
here's a stock 5.9l magnum making 311-327 hp depending on exhaust.
Installing Exhaust Headers Into 300hp Crate Engine - Mopar Muscle Magazine
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From the factory the '92 5.2 with the large diameter exhaust manifolds made 235 NET HP through a cat and large single exhaust.
Later ones with smaller manifolds made 10-15 less.
Most all 5.9 made 245 NET HP, again, through large single exhaust.
That 245 NET HP 5.9 was the first run 300 Gross HP "crate" 360.
Later ones with smaller manifolds made 10-15 less.
Most all 5.9 made 245 NET HP, again, through large single exhaust.
That 245 NET HP 5.9 was the first run 300 Gross HP "crate" 360.
Please quit repeating what you have read on the internet, I had a 5th ave 1985 no 302 heads or roller block.
If the OP heard the engine run, best way to get the truck going on the cheap is to just drop the V8 in and feel the difference. It will not be huge, but not slant-sick powered, not hating on slants, I have owned many of of them in various vehicles.
I can attest I had a 81 D-150 with a slant, drove it for alot of miles, it would get you there but it sucked, even with 4.56 gears, it would not pull snot out of a wet paper bag, the 833 OD has horrible gear ratios. Put the stock 3.55 rear back in it and sold it.
For comparison, I bought a 85 D-150 off my buddy, because I needed a vehicle quick. This D-150 was horrible, slant with an auto, 3.55 sure-grip, it was 100% reliable, started easy but was just **** for a truck, I think that year they were like 100HP, completely under-powered.
Now I have a 85 D-150 with a 440 auto, 3.55 rear, it is stupid fun, forget gas mileage, its more like giggles per mile.
All trucks I had were short-bed trucks, so the same weight.
My BIL had a 77 short bed with a 225 auto circa 2005.
It was a cream puff with low mileage and nice original paint.
Dependable, but barely any power and got the same MPG as his previous 4x4 Warlock with a 318.
It was a cream puff with low mileage and nice original paint.
Dependable, but barely any power and got the same MPG as his previous 4x4 Warlock with a 318.
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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If you are interested in fuel-economy;
After all is said and done, yur still gonna want to get rid of the 3.23s.
The ratios in the A833od are 3.09-1.67-1.00-.73od. Some say these ratios are horrible(see above) And you won't hear me disagree. They can be made to work by carefully coordinating your combo; I have done that.
Now, with the 3.23s and 29s, 65=1777 rpm in od/2430 in Direct. Either gear will get about the same fuel-economy. Unless you can figure out how to give the engine the cruise-timing it needs at 1777, actually, 2430 is likely to be better. That will be the First challenge.
>The Second challenge will be getting the fueling right at those rpms. There is no 4bbl that will operate at a decent AFR, pulling that brick, at 65=1777rpm, until you make it so, and then it will be wrong the rest of the time.
>The Third challenge is driving it slow; chugging along at 650 in Low gear is 5.6 mph. That's about as slow as she'll drive before losing it.
>The Fourth challenge is that 30 mph is; 1123rpm in Direct, 1875 in Second, and 3470 in First gear. As you can see, there is no good gear to use in stop and go traffic.
So here's my point;
Since you gotta change the rear gear anyway, why not do it now, while the slanty is still in it? ........... well I mean , you don't gotta but it don't make any sense to me to try and cruise 65=1777, in a "cheaper than dirt combo"............
The secret to running that transmission is to select the right rear gear, such that Second gear works right, and then building your engine to pull that gear, and let the rest be what it will be .
My combo likes a Second roadgear of ~6.00 corrected to a 24" tire. to get that in your combo with the 29s and 1.97 Second gear, will take a rear ratio of
{6.00/(24/29)}1.67=4.34; rounds to 4.30s With that gear your speed will be 12 mph per 1000 rpm. so;
2000=24, 3000= 36, 4000=48, 5000=60mph, 6000=72mph
Knowing this now; there is NO SENSE putting a big cam in this 318, which will only sacrifice power at 2000, to get it on your budget. Just leave the 318 cam in there and instead, punch up the cylinder pressure.
So what are your other roadgears?
My math says 13.29-7.18- 4.30-3.14 but with 29s, as compared to a car with 27s, this will feel like ;
11.81-6.38-3.82-2.79 almost perfect.
With 4.30s and 29s; 65=2365
IMO, this is altogether acceptable now, which is why I used to run my combo with this gearing.
Now all you have to do is build your 318 up pull that Second gear, hard enough to satisfy your need for acceleration.
First gear at WOT will get you to [email protected]
At the 1-2 shift, the Rs will fall to 2700rpm. So your teener is gonna need some grunt down there, or just do what I did, run first gear up to 5500@36 mph, and Second will come in at ~3000, Thus your powerband will have to start at 3000.
Since most Passenger car cams will be hard pressed to have a powerband much wider than 1500, this points to a cam that power-peaks around 4500, which points to a stock-type duration. But since you gotta wring it out to 5500 in First, your heads are gonna have to make that work.
Aaaaaaaannd, now you know why this transmission is such a PITA , or as @sireland67 says, "it has horrible ratios" .
So by now, your dirt budget is looooonng gone.
What I'm seeing here is a high compression short block, with a re-balanced crank, built to survive 6000rpm blasts, with fancy heads to pull mid-range power out of that tiny engine. It'll probably need a high-lift, fast rate of lift, Solid-lifter cam, adjustable valve gear, good valve geometry, etc. .
what's that all about?
Well, that's about making that very low first gear, (11.81 corrected) get the engine onto the cam, in that very high (6.38), Second gear, so you can have some Second-gear fun.
Do you have to run the 4.30s?
No, you can put a stock 440-2bbl into your truck and forget everything I have said so far. Or
you can do what I did; which was to swap a buncha pumpkins into the back, until I eventually, 4 years later, I landed on the 4.30s, and that was that, with that combo.
The point is that you get the benefit of my experience with that PITA transmission, and it's free.
Ok start saving for heads.
After all is said and done, yur still gonna want to get rid of the 3.23s.
The ratios in the A833od are 3.09-1.67-1.00-.73od. Some say these ratios are horrible(see above) And you won't hear me disagree. They can be made to work by carefully coordinating your combo; I have done that.
Now, with the 3.23s and 29s, 65=1777 rpm in od/2430 in Direct. Either gear will get about the same fuel-economy. Unless you can figure out how to give the engine the cruise-timing it needs at 1777, actually, 2430 is likely to be better. That will be the First challenge.
>The Second challenge will be getting the fueling right at those rpms. There is no 4bbl that will operate at a decent AFR, pulling that brick, at 65=1777rpm, until you make it so, and then it will be wrong the rest of the time.
>The Third challenge is driving it slow; chugging along at 650 in Low gear is 5.6 mph. That's about as slow as she'll drive before losing it.
>The Fourth challenge is that 30 mph is; 1123rpm in Direct, 1875 in Second, and 3470 in First gear. As you can see, there is no good gear to use in stop and go traffic.
So here's my point;
Since you gotta change the rear gear anyway, why not do it now, while the slanty is still in it? ........... well I mean , you don't gotta but it don't make any sense to me to try and cruise 65=1777, in a "cheaper than dirt combo"............
The secret to running that transmission is to select the right rear gear, such that Second gear works right, and then building your engine to pull that gear, and let the rest be what it will be .
My combo likes a Second roadgear of ~6.00 corrected to a 24" tire. to get that in your combo with the 29s and 1.97 Second gear, will take a rear ratio of
{6.00/(24/29)}1.67=4.34; rounds to 4.30s With that gear your speed will be 12 mph per 1000 rpm. so;
2000=24, 3000= 36, 4000=48, 5000=60mph, 6000=72mph
Knowing this now; there is NO SENSE putting a big cam in this 318, which will only sacrifice power at 2000, to get it on your budget. Just leave the 318 cam in there and instead, punch up the cylinder pressure.
So what are your other roadgears?
My math says 13.29-7.18- 4.30-3.14 but with 29s, as compared to a car with 27s, this will feel like ;
11.81-6.38-3.82-2.79 almost perfect.
With 4.30s and 29s; 65=2365
IMO, this is altogether acceptable now, which is why I used to run my combo with this gearing.
Now all you have to do is build your 318 up pull that Second gear, hard enough to satisfy your need for acceleration.
First gear at WOT will get you to [email protected]
At the 1-2 shift, the Rs will fall to 2700rpm. So your teener is gonna need some grunt down there, or just do what I did, run first gear up to 5500@36 mph, and Second will come in at ~3000, Thus your powerband will have to start at 3000.
Since most Passenger car cams will be hard pressed to have a powerband much wider than 1500, this points to a cam that power-peaks around 4500, which points to a stock-type duration. But since you gotta wring it out to 5500 in First, your heads are gonna have to make that work.
Aaaaaaaannd, now you know why this transmission is such a PITA , or as @sireland67 says, "it has horrible ratios" .
So by now, your dirt budget is looooonng gone.
What I'm seeing here is a high compression short block, with a re-balanced crank, built to survive 6000rpm blasts, with fancy heads to pull mid-range power out of that tiny engine. It'll probably need a high-lift, fast rate of lift, Solid-lifter cam, adjustable valve gear, good valve geometry, etc. .
what's that all about?
Well, that's about making that very low first gear, (11.81 corrected) get the engine onto the cam, in that very high (6.38), Second gear, so you can have some Second-gear fun.
Do you have to run the 4.30s?
No, you can put a stock 440-2bbl into your truck and forget everything I have said so far. Or
you can do what I did; which was to swap a buncha pumpkins into the back, until I eventually, 4 years later, I landed on the 4.30s, and that was that, with that combo.
The point is that you get the benefit of my experience with that PITA transmission, and it's free.
Ok start saving for heads.
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AJ I am thinking his tire size is off, a stock tire is a 235-15 which is 28" tall.
It really does not matter, years ago I put 4.56 behind a slant OD, it still sucked.
I did have an 80 d-150 that was not that bad, slant, but the auto went bad on me, put a NP435 behind it, the truck actually pulled good, I was happy with the trans change, but I remember the bell-housing was a sob to find.
It really does not matter, years ago I put 4.56 behind a slant OD, it still sucked.
I did have an 80 d-150 that was not that bad, slant, but the auto went bad on me, put a NP435 behind it, the truck actually pulled good, I was happy with the trans change, but I remember the bell-housing was a sob to find.
MopaR&D
Nerd Member
The crank and rods in a 225 are so heavy it ends up using all its power just to get that internal mass moving instead of accelerating the vehicle once shorter gears are put in lmao. I wish so badly Chrysler made a diesel variant, it's literally already built like one.
MOPAROFFICIAL
Oogliboogli
Because 'as cast'...The 302 head is the worst flowing head mopar ever made for a small block dodge.
Yep! Even the late seventies to early eighties standard duty open chamber 183 smog casting 318 has a better looking intake port.
junkyardhero
Well-Known Member
to OP, didn't you roll this around the other week about whether you wanted to swap to a V8 but you had mentioned reservations in that this is your daily right?
lud
Well-Known Member
My friend... your standards and expectations are much higher than mine, but I can get that slant hulling pretty quick, I can only imagine a 318 in there. I'm not building a race car, or the perfect daily driver. I want what I got now, but with that v8 sound and more power. For example I drove past some kids playing sin their yard yesterday and they did there little hand signals they do for rev it up, do a burn out, etc... all I could do was roll on by, felt pretty lame lmao. If I could of just dumped the clutch and let her eat and it did something other then sound like it was gonna explode that'd be awesome. The slant is not a rev happy little motor.. and like I said, I have done some impressive things with this engine even though it's probably only making 190 horses... 300hp 318 is all I'm looking for.
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lud
Well-Known Member
I have another vehicle... and I've just had it with this engine, it's become a money pit, money spent on an engine that I won't appreciate until I'm wayyyy older (im keeping it for something else). For right now I want a cheap tire roasting fast pull anything I need kinda truck. And this seems like the easiest route. And to be completely honest a learning experience. I have never completely rebuilt and engine before, but I'll have help when needed. I just want to take the time and say thank you I very much appreciate every single response in this thread I have read everything over very carefully and with consideration. Much appreciated. Friday I'm going to go talk to the dude and figure out a deal. The parts truck drives. But I checked the oil stick when I was out there yesterday and it was way over full and smelled of gas. Any ideas?
MOPAROFFICIAL
Oogliboogli
Terrible amount of shrouding, terrible.
Once they do flow...you realize you could have spent barely half that time on any of the open chamber versions and better numbers. The novelty is how terrible it is from the get go turning out any decent numbers at all. Theres no testing out there to determine if that chamber once massaged is more beneficial than the early closed version.
There are cult followings for everything..and they hate hearing that anyone reputable talking down on their iron idols
Slants ain't for everybody, that's a fact. The 318 will be cool. I like um all.
1990 318 TBI Roller Engine, stock 9.2:1 cr with the 302 factory closed chamber heads and stock roller cam. All Stock.
Add the Edelbrock 1406 4 barrel carb and 2" dual exhaust and you are good to go.
Great performance with the 4 barrel. Just keeps on pulling, never floated out the stock valve train once > just keeps on pulling.
No need to port the heads, they perform fine as they are.
1990 Stock 318 Roller
w/truck engine mounts.
302, 714 stock closed chamber heads, same same.
1976 D100
318 Roller Engine
727 Automatic
3.55 Rear Gears
Great drivability, performance, and mileage.
Do it again? Heck Yeah!
Note:
Used to be slant 6 with manual 3 speed and clutch.
(Night and Day difference going to the V8, total different truck.)
☆☆☆☆☆
Add the Edelbrock 1406 4 barrel carb and 2" dual exhaust and you are good to go.
Great performance with the 4 barrel. Just keeps on pulling, never floated out the stock valve train once > just keeps on pulling.
No need to port the heads, they perform fine as they are.
1990 Stock 318 Roller
w/truck engine mounts.
302, 714 stock closed chamber heads, same same.
1976 D100
318 Roller Engine
727 Automatic
3.55 Rear Gears
Great drivability, performance, and mileage.
Do it again? Heck Yeah!
Note:
Used to be slant 6 with manual 3 speed and clutch.
(Night and Day difference going to the V8, total different truck.)
☆☆☆☆☆
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lud
Well-Known Member
Bad to the bone truck, can't wait, lookin at the engine with the dude friday (gonna try to get the whole truck but wouldn't count on it cuz the springs are so much better than mine etc..) I got a lead on a bellhousing to match up the 318 to my 4 speed, and a lead in some 318 magnum heads. Gonna rebuild from ground up, new performance HEI system, water pump, oil pump, plugs n stuff (whatever cam seems like itd work) make everything work how it should. Thannnn... dump it into my truck and start adding more to it. Headers, valve covers, intake, carb, you name it. But afterwards. important stuff first, get her back on the road and in a daily drivable state. I'm probably going to have to get the block and heads milled n stuff... (I plan on driving this Truck a long time) unless they look good, I've yet to see the odometer... or what the gas pedal looks like... but in the process of getting the stuff at a machine shop, should I bore it over or anything special?
lud
Well-Known Member
That truck use to be red... amazing what some sand paper and spray paint will get done lmao
Maybe get it running and do a compression test first. See if there’s anything that’s begging for attention. If you’re bound and determined to rebuild it anyway, how much are you budgeting towards it? Dig around on the truck and see if maybe a reman or junkyard engine has been swapped in. Casting numbers and casting dates along with the numbers stamped on the front of the block below the drivers side cylinder head wil tell you much.
Also, if look at those years of trucks, look for leaks around the windshield and at the roof near the windshield. They’re condensation traps and notorious for leaking from rust starting inside near the windshield pinchweld seams and working it’s way out.
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