Good evening all, I am new here and new to older Mopars, I just bought a 73 duster project an have what I believe to be a 74 318la block with newer (early 80s heads) hard to tell because the casing numbers are on the bottom of the heads. If this is true is it worth putting money into the heads for more power or are they not really worth it?
Mopar 318 heads
- Thread starter Dusted73
- Start date
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Can 318 head be modded to make power yes , worth it ? probably not.
What are you looking to get out of your combo?
As is stock 318 heads can support about 300 hp, stock 360 1.88 valved heads about 375 hp, magnum 400 hp.
What are you looking to get out of your combo?
As is stock 318 heads can support about 300 hp, stock 360 1.88 valved heads about 375 hp, magnum 400 hp.
I'm looking for right around 350-400 end goal, but getting it on the road is more of a priority at the moment. The motor has no intake manifold or carb and all the ignition is missing aside from a brand new distributer so I don't even know if it runs but the heads looked really good when I pulled valve covers and the motor spins freely with what feels like good compression.
pishta
I know I'm right....
casting numbers are on the top of head also, look around the left most intake runner.
Before we start off you'd probably be better off with a good running 5.9l magnum.
The base Hp/TQ is a stock longblock 5.9l with 4bbl and headers.
Getting that out of the way, there's a 318 build stock long block "low cr" 4bbl headers and a comp cam xe262 making 282hp at 5000 rpm.
After that the problem with 318 is it's cr, limits the size of the cam you can use and 318 head flow limit the power you can make, could use 340/360 heads but they will drop the cr even more.
Magnum will give you enough air flow to make 400 hp, but you might as well use the whole magnum engine, porting 318 is an option if you can do it, but you could probably buy some aftermarket by time your done sinking money into the stock head that might flow as good as a 360 1.88 valve head.
The base Hp/TQ is a stock longblock 5.9l with 4bbl and headers.
Getting that out of the way, there's a 318 build stock long block "low cr" 4bbl headers and a comp cam xe262 making 282hp at 5000 rpm.
After that the problem with 318 is it's cr, limits the size of the cam you can use and 318 head flow limit the power you can make, could use 340/360 heads but they will drop the cr even more.
Magnum will give you enough air flow to make 400 hp, but you might as well use the whole magnum engine, porting 318 is an option if you can do it, but you could probably buy some aftermarket by time your done sinking money into the stock head that might flow as good as a 360 1.88 valve head.
Wyrmrider
Well-Known Member
what 273 said
what cams in it now?
get it running with what it has unless noo or bad cam
256 lunati is better than 262 comp
compare the lifts
shorter cam will have more low and mid range
no comp shorter than 275 is best for a chrysler
what cams in it now?
get it running with what it has unless noo or bad cam
256 lunati is better than 262 comp
compare the lifts
shorter cam will have more low and mid range
no comp shorter than 275 is best for a chrysler
If I run what I have will I be able to use the brand new intake manifold I buy for my 318 on a 5.9 magnum? I'm looking at the weiand action plus intake with a edlebrock 1406 carb and a set of headers and hei ignition mod, and swapping out the 7 1/4 rear with a Ford 8.8 with 3.73 gears out of an exploder.
Magnums take a different bolt pattern, some intakes have both, don't think yours would.
You can do a 318 might want to lower your expectation, are you rebuilding ? a set of piston, for better cr opens up head choices to and 340/360/magnum aftermarket.
but if your rebuilding you still might want to think about getting a 360 LA to start with, not trying to talk you out of the 318, if your doing more then cam 4bbl headers, it's usually better off starting with 360/5.9l, it's gonna be making an extra 20-40 hp through out 1000-5000 powerband where most street engines need it.
You can do a 318 might want to lower your expectation, are you rebuilding ? a set of piston, for better cr opens up head choices to and 340/360/magnum aftermarket.
but if your rebuilding you still might want to think about getting a 360 LA to start with, not trying to talk you out of the 318, if your doing more then cam 4bbl headers, it's usually better off starting with 360/5.9l, it's gonna be making an extra 20-40 hp through out 1000-5000 powerband where most street engines need it.
MOPAROFFICIAL
Oogliboogli
Yes
The route I’d take is an all Edelbrock top end and just use the cam you want.
RPM heads
RPM Air tap intake
650 AVS II
Cam of your choice
Dual exhaust, manifolds or header, headers are a plus. I have used and will do again Summit headers and there dual exhaust kit with there turbo mufflers and there H pipe.
Use the 318 heads if you can do the work yourself. Otherwise, cut them up for fishing weights and door stops. If you can do the work, install 1.88 360 valves and port away!
RPM heads
RPM Air tap intake
650 AVS II
Cam of your choice
Dual exhaust, manifolds or header, headers are a plus. I have used and will do again Summit headers and there dual exhaust kit with there turbo mufflers and there H pipe.
Use the 318 heads if you can do the work yourself. Otherwise, cut them up for fishing weights and door stops. If you can do the work, install 1.88 360 valves and port away!
MOPAROFFICIAL
Oogliboogli
234's are truck heads. Late 60's.
They have a water heated cross over.
You can use them blocked or not. I block them. If you go with better heads, I'd take those off your hands.
2658234 are listed for 66 273 and 67 318. They should be small valve closed chamber heads.
MOPAROFFICIAL
Oogliboogli
Shhhhhhhhh. They're junk! ;)
They work but if you want to make 350-400 horse you will have to machine them for 340/360 valves, should have hardened seats, and at least port match and bowl blend. You could easily have $$ wrapped up to make them work unless you can do all the work yourself. Reasonably priced aluminum heads now days are really a bargain.
MOPAROFFICIAL
Oogliboogli
Yeah, he should toss them this way.
They really aren't worth much.
PRH
Well-Known Member
If the goal is an honest 350-400-ish hp, and have it be a pretty basic build....... I’d suggest getting a 360 to start with.
You can do it with a 318, it’ll just cost more....... and have less tq.
You can do it with a 318, it’ll just cost more....... and have less tq.
Okay, what do you guys think id be at for hp if I did a cam, intake manifold and 4bbl? I just bought the car and it needs a bunch of work so plan is to get it running and stopping then wiring last, if I could get 300 I'd be happy to run it for a few years and then worry about engine swap down the road. I was thinking weiand action plus intake and eddlebrock 1406 carb, the reason I chose the weiand is because of the small port heads i thought I read that a air gap was made for 340/360 heads and I would loose Hp. But I haven't ordered anything yet just looking for some advice, I'm new to the mopars and so far it's so much more confusing than the small block chevy world.
PRH
Well-Known Member
Lots of variables, but 250-300hp shouldn’t be an issue.
Don’t get hung up on the HP numbers.
Come up with a pile of parts that will all work well together...... and iiwii.
Don’t get hung up on the HP numbers.
Come up with a pile of parts that will all work well together...... and iiwii.
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Read up on 318 cams. There are as many opinions as there are members here. There is no "magic bullet" cam for a 318. They are easy to over-cam and then you will be changing rear gears and torque converter to make that cam work. (along with intake, carb, headers or HP manifolds and exhaust.) We are at $2-3000 with bolt on's just to make the cam work.
Am I on the right path with the weiand action plus intake manifold and eddlebrock 1406? If so what cam should I use? Rear gears will be a 3.73 Ford 8.8 and the transmission is a 904 stock i would believe.
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The intake and carb is a good combo. You will need to match your heads, exhaust, converter, and rear gear to the cam.
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