318 head porting for the average joe

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I agree there is only so much out of a 318 head vs say a j head. main reason is its two different castings and the runners are cast bigger in the 360 head. You simply cannot hog a 318 head out big enough to match a J head.
 
I agree there is only so much out of a 318 head vs say a j head. main reason is its two different castings and the runners are cast bigger in the 360 head. You simply cannot hog a 318 head out big enough to match a J head.

And the port on a 340-360 head is too small for even 318 inches. Even at 5500.

So you jam more cam in it to make it rpm and the torque takes a massive hit.

More torque and driveability is killed by a big cam than a head thats “too big”. I see it all the time.

Where did my torque go? Well, you **** the torque because your heads are too small, the cam is too big and you don’t have enough compression to get it back.

And then the crying starts…
 
Nobody is stuck building anything. If you have an original 273 car, pull the thing out and build something else, if you want something and don't care about making good power don't waste your time porting on a 318 head, air velocity is great until you run out of steam at 5300 because the port is too small. A 340-360 port with a burr finish will out perform a lil twerp 318 in a running vehicle and on a flow bench or Dyno.
That's like paying $3500 to have someone port 906 Chrysler big block junk heads.
Why ?
I guess some people just wanna play with there benches and make threads about cartridge rolling a tiny bowl lol.
I build cylinder heads all day, everyday & some are just better than others and that is a fact.
 
And the port on a 340-360 head is too small for even 318 inches. Even at 5500.

So you jam more cam in it to make it rpm and the torque takes a massive hit.

More torque and driveability is killed by a big cam than a head thats “too big”. I see it all the time.

Where did my torque go? Well, you **** the torque because your heads are too small, the cam is too big and you don’t have enough compression to get it back.

And then the crying starts…
Problem is people don't know how, where or what to start with building a engine. As you know...it's all gotta live and work together, 1 thing wrong it all suffers, everything correct, all is good.
 

I think there is alot of 318 hype these days and the record needs set straight. Yesa a 318 is a good engine it is not designed as a performance engine It doesnt mattter what Uncle Tony or any other 318 drum beater says about it being the 340s little brother its simply not true the 340 is a redesign. They wouldnt have redesigned it if they could have modded a 318. there is nothing a modern day backyard mechanic knows that Chrysler engineers didnt know in the 60s when designing these engines. And even if so its too expensive to do now. The most affordable way is to start with the right engine to begin with. It has to be like the difference between riding a Honda 350 then getting on a crotch rocket to explain to some people. I will finish with this, sure build a 318 but don't get crazy with how much money gets spent, it's difficult to get back when you decide to go 340 or 360. This is why you see 318s for $1000-$1500 etc. I believe alot of this is modern day hype because 318 owners want to believe they have something special, its not it was a mass produced engine made by the millions they used to be in junkyards everywhere and free from guys swapping in 383s that were pulled from yards etc. Ok I will stop now :thumbsup::lol:
 
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You guys are polluting this gentlemen's thread.
You wouldn't get off so easy back in the wild days. lol
 
You guys are polluting this gentlemen's thread.
You wouldn't get off so easy back in the wild days. lol

How is saying the truth polluting a thread?

I can’t see any reason to port a 318 head. Ever. Simple as that.

You will have guys who will want to and I say go for it if you want to learn.

Other than that, it’s just dumb to even put a burr in the grinder to port a 318 head.
 
I can’t see any reason to port a 318 head.
First off, this thread was started almost 15 years.
Secondly a good cylinder head porter doesn't care what he's porting, it's the customer's choice.
I think it's great someone is putting some effort in cast iron, it's becoming a lost art.
I get it, aluminum heads are so much nicer to port, but then again they come halfway there, most pickup significantly with a quality valve job and some bowl work.
 
First off, this thread was started almost 15 years.
Secondly a good cylinder head porter doesn't care what he's porting, it's the customer's choice.
I think it's great someone is putting some effort in cast iron, it's becoming a lost art.
I get it, aluminum heads are so much nicer to port, but then again they come halfway there, most pickup significantly with a quality valve job and some bowl work.
Good cylinder head porter is realistic about what he's porting too.
 
First off, this thread was started almost 15 years.
Secondly a good cylinder head porter doesn't care what he's porting, it's the customer's choice.
I think it's great someone is putting some effort in cast iron, it's becoming a lost art.
I get it, aluminum heads are so much nicer to port, but then again they come halfway there, most pickup significantly with a quality valve job and some bowl work.


Yup, you missed my point. How many 318 heads have you ported and what are the results?
 
Damn straight. Wasting time and money on porting when you can get a better casting to start with is madness. It’s not economical either.
I know it's not 1980, I only had 915's to work with for the 383. lol
My uncle sure knew his **** and helped me out a bunch, I think I might have learned a little something.
 
This is a merry-go-round thread, as its been way too long in finishing!
I approached the magician that is DV and asked if he would examine and dyno my 1969/70 W1 engine.

He was talked into doing the worst thread in Mopar history a 2BBl 318...
We all know its a 'fool's errand' but folks still want to read and make comments.

Looks like DV will be remembered for this farce and all his previous good work is forgotten.
But it will be finished and folks will say ''its all nonsense''...:mob:

Sorry it on its side.

Weslake heads closed.jpeg
 
The W1 Nascar engine of 1969/70, a replacement for the banned hemi 426.
Developed in the UK by Weslake engineering, a Passenger car 426/400 head with heat crossover.

The W2 to which folks are more familiar was a spin-off of the unknown W1 head.
Weslake never got the recognition for the development work.

But one set of W1 Nascar heads are still here in the UK.
They are part of a full Dyno engine that was going to be inspected and run by DV.

But the infamous 318 2BBL has got in the way and has killed this better thread.
Be careful what you wish for, as hell is paved with good intentions...:BangHead:

Ovalport 'Weslake one' intake ports.jpg


D-port exhaust Weslake head.jpg
 
Andy Wood and DV should have never entertained Uncle Tonys idea. Yes it got them clicks and views I get it Tony is good at clicks and views. But if someone is waiting for this miracle 318 build it will never happen it's too costly an endeavor IMO. I mean DV started grinding on 1 rod then bailed its too time consuming grinding on and lightening those heavy Mopar rods etc. then they need donated parts etc no one these days can afford to give things away even rich guys don't do that. these are ethe reasons why MI 318 will never happen its an Uncle Tony pipe dream blown up in their faces . It cannot be done cheap and Tony knows it, but he also knows his audience.
 
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Some of you guys forget that not every build is a max effort build. My stock 318 heads needed rebuilt. I found some 302s that already had 1.88/1.60s in them for cheap. Moparofficial’s and other threads (like this one) and videos helped guide me through the process. I’d never ported anything before and tbh I’d rather learn on some cheap heads than something else. Anyway. Heads and headers did abundantly more for my car than going from 2.76 to 3.92s. I turned on music, sat with a drill and carbide bits for a couple days and just chilled. Enjoyed the learning process. I’m really happy with the results and that’s all that matters. And all that matters for most of us.

Could I have gotten more out of a 360 head to begin with? Sure. I could have also gotten more out of nitrous. Or a bigger cam than what I put in it before. Or 4.88s. Or out of building a fox body. Or out of a rail car. Or a big block. Etc etc etc..
 
I ported 318 675 heads, I guess I'm wrong to do so, because I wasted my time according to some of the old farts of wisdom. I'm not building a race engine, it's just a peppy grocery getter. I have another set of of 675 heads, maybe I should waste my time on those too. Maybe just a quick worthless touch up to clean off the nasty casting slag just too waste some time. Or maybe I should just leave the ugly booger casting alone?

20230318_172730.jpg


Ok, to be realistic, we just want to learn and have fun. Some people use their time to do some things different than others and that is fine. Have realistic goals and do it because you want to. Porting Mopar 675, or Ford E7TE door stoppers is fine if the goal is realistic and you don't expect to have a track monster on a low budget. A peppy runabout is more realistic and if that's the goal, that's fine. However, anyone can build whatever they want and spend whatever they want and that's fine as long as they realize the bad investment they are making. Lol, it's not my money.

Alright, now my take on the "Mission Impossible" nonsense. It's doomed. No really, this project went so far off the rails, I don't even consider it a "Mission Impossible" project anymore. It would have been very interesting to see what could be done with 318 using only stock factory or stock replacement parts. Practical? No. Curious? Yes. DV went off the rails and decided that he was going to use non factory or non factory replacement parts which would just make it a modified 318 with some bolt on goodies. That's far from the original objective. Really I and many others have put together a 318 that's more true than his off the rails idea. This created issues with UTG. From the beginning this project was supposed to be a group effort with UTG who had the original idea, DV and Andy. Then the other guy started coming in which would be Servedio. UTG who was not getting updated or involved in the decision making and felt like things were going off the rails, which they were and respectfully backed out of the project. "Mission Impossible" was UTG's idea so I'm sure he felt frustrated.

On to other M.I. problems. DV pretty much let Servedio do most of the R and D work and they had an idea of what could work in theory. The problem is that other than the heads and manifolds, the parts were never completely ready so the engine could be assembled. In fact the lower end parts that UTG gave them were "unusable" according to DV and Andy. They had a set pactice budget I'll call it because that doesn't include the experiments, and UTG just pretty much dropped off junk that was just good for R and D, so they needed everything for the bottom end. Machine shop work is not cheap and I do believe was factored into the budget, so unacceptable junk would require too much machine work to stay in budget.

In the end this whole group project was a group disaster that eventually fizzled out and now has maybe come back again with Andy from Unity Motorsports Garage in charge. So far not much has happened in five months and has been a huge disappointment for the viewers. I am sure the original intent is no longer there even if it ever gets finished. The Mission Impossible 318 project is tarnished, even if they go back to the original goal, it's a disaster no matter what the outcome is.
 
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Wow Ant, someone talking sense about the MI disaster at last!
Its all been done before , BUT folks like grinding on 50 year old junk iron.

''Nothing to see here'' and DV knew this, so he got out asap without upsetting folks.
Andy will now finish the MI 318 in some shape or form, just a stepping stone to a 400hp build.

The problem is here the hardcore racers are amazed that Plebs (like me) like old factory iron.
My goal was to run a NINE with a factory iron 440 in a B-body.

Now its how fast can I run in an A-body with a factory iron engine...:realcrazy::thankyou:
 
The problem is here the hardcore racers are amazed that Plebs (like me) like old factory iron.
That's what it seems like. A bunch of race snobs that get stuck in the same groove they dug up a long time ago. The problem is just not here too unfortunately.
 
Yep the hardcore racers do not understand the factory iron guys at all.
They have no concept of someone spending a week grinding a junk iron head!

''What's the point they will say'', but some folks like to keep their cars original.
So they massage what they have and see big-port Aluminum heads 'a step to far'.

I just did a 318 for a friend, closed chamber 66 heads, forged pistons and later heavy rods.
He thinks he has got a flying machine now, with around 300 horsepower!

Different strokes for different folks.
Live and let live.:mob::poke::thankyou:
 
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