Mopar 318 heads

-
I'm new to the mopars and so far it's so much more confusing than the small block chevy world.
Click to expand...

Once you get more familiar with them you’ll likely find they’re actually easier, since there are less variants.

When you really get into the weeds, there are a ton of different stock pieces for the SBC....... many of which kinda suck if you’re trying to make power.
 
Cams? You’ll get 100 answers on that.
I’d use something fairly small, that’s easy on parts for the type of build you’re talking about.
But, ultimately you’ll have to weigh all your options and make a choice.
 
toolmanmike said:
The intake and carb is a good combo. You will need to match your heads, exhaust, converter, and rear gear to the cam.
Click to expand...
I'm going to run the stock 234 valve train 3.73 gears, 904 transmission with a stock converter im guessing. I'll run a cheap set of headers 2 1/2" exhaust and some glass packs to start with. What is you advice on a cam for that set up?
 
With 3.73 gears, a reasonable stall converter with stock heads on a low compression 318, you can use a street cam with as high as a duration @.050 of 228 and make very good power. Now I can’t finger the number and even more so with the missing variables. But this would be a pretty good street combo that would approach your goal.

PRH is a head ported in your geographic area in which I would (or if he would be OK with doing your heads) send the heads to for some work IF the price of the work is within your wallet.

The catch of reworking and some porting of an old iron head is very close to an aluminum head. The price difference normally warrants taking a pause since the price difference is small but the heads abilities are much greater making it well worth the price for many.

I am not against iron heads.
 
Dusted73 said:
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.
Click to expand...

318 Long Block Bolt Ons - Tech Articles - Mopar Muscle Magazine

318 Small Block Build - How To - Hot Rod Magazine

Some people will say those engines don't make that much cause there magazine builds, but like I most don't have a dyno nor have had anything dyno'd, so I think most of us are talking about magazine numbers anyways when we say 300 hp 350 hp 400 hp etc..
 
Dusted73 said:
I'm going to run the stock 234 valve train 3.73 gears, 904 transmission with a stock converter im guessing. I'll run a cheap set of headers 2 1/2" exhaust and some glass packs to start with. What is you advice on a cam for that set up?
Click to expand...

Stock converter? That changes the cam mentioned above. Since that is the case, a stock converter, a duration @.050 not more than [email protected] will work great! Been there done that exactly like your doing.
The 228 cam might be a bit much for the stock converter even though you have 3.73 gears. This I’m not sure of.

Use Summit headers and there dual exhaust kit and if you can splice in there H pipe kit, go for it.
 
Dusted73 said:
I'm going to run the stock 234 valve train 3.73 gears, 904 transmission with a stock converter im guessing. I'll run a cheap set of headers 2 1/2" exhaust and some glass packs to start with. What is you advice on a cam for that set up?
Click to expand...
I found the Hughes Whiplash 318 cam interesting. I have one but haven't installed it yet. #SMC1326AL Hughes Engines

318 Whiplash.PNG
 
Last edited:
Depending on your compression
look at Lunati Voodoo or Howards with a 15 in the catalog comments catalog pick the rpm range you want to run
given a choice choose the smaller of the choices
The Whiplash intake is ok The exhaust is way too long for headers, sucks gas big time and kills your expansion ratio by opening the exhaust early for that "sound"
you do not need all that lift on the exhaust either
way too much overlap
 
I’d wait on the cam decision until things are a little farther along, so you know what the actual CR is, and for sure what the converter, gears, and exhaust situation is.
 
273 said:
318 Long Block Bolt Ons - Tech Articles - Mopar Muscle Magazine
Click to expand...
I gotta tell ya, a lot of people crap on these dyno reports with various reasons that could be true to a point for someone somewhere....

Having used a Crane cam with super close specs produced a pretty good 318 runner for me. The first few times out sucked until I got it more dialed in. After I sold the car, the next owner took it to the track and ran close to 340 times with it in the mid 14’s.

This is also a good cam for a 318 project.
 
Thank you guys all for the help, I'll be able to put more money into the drive train is proven to function, so I guess I'll skip the cam for now and work on getting it running and stopping. I have no idea the shape of the tranny either so I guess I'll start with that weiand action plus and eddlebrock 1406 and put fuel and spark to it and see how she does. I just wanted to make sure that the intake and carb was a good start of something I could grow in to, I'd hate to spend 600 on parts just to have to buy a new intake and carb when I do heads and a cam and maybe even a slight bore to freshen the motor. Its hard because a lot are saying go 360 where others are saying stay 318.
 
Dusted73 said:
Thank you guys all for the help, I'll be able to put more money into the drive train is proven to function, so I guess I'll skip the cam for now and work on getting it running and stopping. I have no idea the shape of the tranny either so I guess I'll start with that weiand action plus and eddlebrock 1406 and put fuel and spark to it and see how she does. I just wanted to make sure that the intake and carb was a good start of something I could grow in to, I'd hate to spend 600 on parts just to have to buy a new intake and carb when I do heads and a cam and maybe even a slight bore to freshen the motor. Its hard because a lot are saying go 360 where others are saying stay 318.
Click to expand...


That’s the best thing getting it going, you can always do hop ups later, any bolt on to a 318 can mostly be used on a 360 later if wanted.

PS. There’s nothing wrong with doing a 318 just a 360 is gonna make 30-50 more power through out the rpms we normally drive in on the street, 1000-5000 rpm.
For the same money. That’s up to you.
 
Wyrmrider said:
Depending on your compression
look at Lunati Voodoo or Howards with a 15 in the catalog comments catalog pick the rpm range you want to run
given a choice choose the smaller of the choices
The Whiplash intake is ok The exhaust is way too long for headers, sucks gas big time and kills your expansion ratio by opening the exhaust early for that "sound"
you do not need all that lift on the exhaust either
way too much overlap
Click to expand...
Yep, "that sound" . That's why I haven't put it in yet. Love the sound but there are better cams out there for stock teen's.
 
I don’t see that much HP between the two engines in this low power build up. No way.

@duster73, I have a Weiand Stealth and there is no provision for mounting the coil. Also, the bolt holes are to close to the runners to get the attaching bolts I .
I also would say there was also a fair amount of core shift on mine.

Several shots of multiple bolt holes to attach the intake to the head that needed modifying in order to accept the reduced head size of 3/8 on these ARP bolts.

Id get a Edelbrock intake of any dual plane kind first if I change intakes gain. (And I will.....)

E9E98FFD-BE4B-42ED-943E-6C926D03DDDB.jpeg
044334E5-7914-4B5A-BCD3-ED29A476F5A1.jpeg
3DA0112A-89D4-4DF8-AA1C-AB3F08FD4123.jpeg
32D7A432-C93B-4978-9931-AFFD07CC21D1.jpeg
248B932B-4F26-4C5D-B6AA-C4DE3D39D2AD.jpeg
 
Last question for now, im about to place my order with JEGS, what are the best budget headers for a 73 duster with power steering, as far as install wise?
 
MOPAROFFICIAL said:
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.
Click to expand...
Why do you block them? And how do you block them, I am unfamiliar with these heads.
 
do do a compression check and make sure all is ok before proceeding
also how's the timing chain

what the mopar muscle article (link above) said
We elected to go with a Competition Cams XE262H, a hydraulic grind spec'ing out with a gross duration of 262/270, delivering 218/224 degrees open time at .050 inch tappet rise and .462/.470 inch lift on the intake and exhaust sides, respectively. (218 is 10 degrees bigger than the 340 Magnum cam nut look how much shorter the seat to seat is- close to 16 degrees adjusting for lift ad adv duration see why I say the 340 smog cam is LAZY- it is giving an EGR effect)

Another good choice would have been Comp's smaller XE 256H, which shows a somewhat " fatter torque curve down low." (for stock gears)
"Higher camshaft should be reserved for combinations with more flow potential from the cylinder heads and a higher level of static compression."

Now personally I'd never use a comp under 274hl
here I'd use the Lunati 250 or 256
compare the lift with the comps in the article you will find similar areas under the lift curve but shorter seat to seat
you pick up torque on a low compression build
Big as I'd go is the 256 Howard
all these have different LCA's so there are some choices
For my on personal engines I've used the Jones 256

holding off on the cam is a good idea unless yours is trashed
and do not spend money on roller tip rockers
there are other more important things- like suspension and stopping
 
Last edited:
You must log in or register to reply here.
-

Back
Top