318 head porting for the average joe

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I wouldn't put x heads on a 318.
That being said, xheads were the 1st set that I did a decent amount of DIY porting. That is on my 340.
Don't go crazy, be careful. X heads are notoriously good iron oem heads. Yes they can be made better with cleanup and porting.
Sorry to jump into an old thread but this is right around the question I’m trying to figure out. My 318 is running the larger valves 2.02 and 1.60. The heads were ported a bit by the previous owner. He states he “gasket matched” the heads and intake the best he could but isn’t a “pro”. I haven’t had the motor apart to closely inspect but it does seem snappier than I would have thought. My question is this after reading this thread I’m still not sure if I should go after a set of local 340X heads and start porting etc or is that not worth the squeeze with a set of worked 318s I have? Sorry if this is repetitive just learning here.
 
Check out Charles Servedio’s YouTube channel.

He did a bunch of work on some 302’s and a set of open chamber heads.
He has also done magnum heads.
Also W2 and X heads for fish.
Ain’t that right Bob?
 
He has also done magnum heads.
Also W2 and X heads for fish.
Ain’t that right Bob?

LOL! I guess that post has a for me???

Charlie did indeed grind on a Magnum & my “J” head for me to copy myself after I get my garage up and running. He also did do a set of race W2 heads. Flowed on a 4 inch bore plate to 323 cfm - IIRC.

Charlie is doing research and development on a 318 head for David Vizard’s “Mission Impossible” 318 project he took over from Uncle Tony. YouTube both of these names for further information on the project.

Off hand, I don’t know what the latest cfm topped out at or the flow curve to the 318 head. Do note the small valve size. Also on that note, I’m not sure what exact 318 head he has. It is an open chambered head.

Here is a link to one of Charlie’s videos. It’s a bit of a tech video. If your not into the tech side of porting and you just want to see some flow numbers of this head, fast forward some and you can see how the head flows at many points including cam lifts that 99.9% of you guys would never go.

 
Its all about optimum port flow for the job at hand.
If you are a grocery getter 318 then small ports are perfect.
If you are a 7000rpm screaming 318 (@+60)/340/360 then X-heads will be fine for you...
 
I know that some people talk about terrible the stock casting is on these old heads. While porting my 675 heads I have seen how bad the stock ports really are and well... they bad and they ugly. Some ports were casted off center and the casting slag was horrendous.

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Its all about optimum port flow for the job at hand.
I agree, But
If you are a grocery getter 318 then small ports are perfect.
A so called 318 port was basically designed for a 273 an engine that's 45 cubes smaller and that head is not really designed to make any real amount of hp with any displacement. Saying that a 273/318 heads aren't too bad if looking to make under 300 hp with moderate cam sizes.
If you are a 7000rpm screaming 318 (@+60)/340/360 then X-heads will be fine for you...
The X head was mainly designed for a 275 hp 340 @ 5000 rpms, Not 7000 + rpm screamers that's what W2 where designed for.

There's nothing wrong with 340/360 type heads on a 318 if looking to make 300 + hp or even on a 273 if goal is the same. (yes you'll need to do something about CR).

And yes you can port and add 1.88/1.60 to a 318 head if you can do so, but your basically making a J head.
 
Saying that a 273/318 heads aren't too bad if looking to make under 300 hp with moderate cam sizes.
That's good enough to make a 3200 lbs car with the right gearing feel peppy kind of quick. If people want something with some pep but don't want to easily break parts, then that is the direction they should go.
 
A so called 318 port was basically designed for a 273 an engine that's 45 cubes smaller and that head is not really designed to make any real amount of hp with any displacement.
That's funny a lot of local guys run 11's with less cubes (308 CI) with a head of similar size in street cars.

As a matter of fact some one will sell you an engine (308 CI) with a mild cam and stock valves sizes similar to a 273 that will run 11's.

These engines are designed for the budget minded who are looking for a low maintenance efficient engine that they can use in their everyday driver, but still drive to the track and run a mid to high 11 second ¼ @ 112-115mph with 3,000 rpm convertor and 3.5 gearing.
 
I have a set of 302 heads here on the shelf fresh from the machine shop (ok 3 years ago but still not mounted on an engine) and yes I plan to pull them apart this summer and clean them up, mostly just casting flaws and yes I'm gonna RUN THEM... On a 318, even.
Tough. Not going speed master, not yanking my 318s for 360s, nothing of the sort.

Ok let the boo birds chime in.... Too bad it's what I'm doing.
And I have a 2nd set of these heads to get thru the machine shop so I can do the same thing to them.... They're what I have, and they're what I'm gonna use....... Can't be any worse than the 163 heads I have now..... (These 163s are original to my engines)
Don't have the money for speed master and wouldn't want them if I did because I am trying to keep the chinesium content as close to non-existent as humanly possible.
If I had the money for aluminum id probably buy the Eddie's.
 
That's funny a lot of local guys run 11's with less cubes (308 CI) with a head of similar size in street cars.

As a matter of fact some one will sell you an engine (308 CI) with a mild cam and stock valves sizes similar to a 273 that will run 11's.

These engines are designed for the budget minded who are looking for a low maintenance efficient engine that they can use in their everyday driver, but still drive to the track and run a mid to high 11 second ¼ @ 112-115mph with 3,000 rpm convertor and 3.5 gearing.
That's nice, is there a point that's relevant to the average dude (with average skills, time, money etc..) building a 318 ?
 
That's nice, is there a point that's relevant to the average dude
That's the problem isn't it. Your arguments seem to produce average results yet other people out there manage to make more impressive power with less.
 
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I have a set of 302 heads here on the shelf fresh from the machine shop (ok 3 years ago but still not mounted on an engine) and yes I plan to pull them apart this summer and clean them up, mostly just casting flaws and yes I'm gonna RUN THEM... On a 318, even. Ok let the boo birds chime in.... Too bad it's what I'm doing.
And I have a 2nd set of these heads to get thru the machine shop so I can do the same thing to them.... They're what I have, and they're what I'm gonna use....... Can't be any worse than the 163 heads I have now.....
Nothing wrong with that, obviously if your hp goals aren't high, 200-275hp than stock 318 heads are fine, but at some point if the goal is more power something has to be done with the heads and for most especially people that aren't gonna port your gonna have to move up to some type of 340/360/magnum head, no matter how hard Hysteric champions the SMALL.
 
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That's the problem isn't it. Your arguments seem to produce average results yet other people out there manage to make a more impressive power with less.
This ain't a pro engine building site, so how a pro would go about a lot of the time has very little bearing on most of the builds on this site, Know your audience.

The title of this thread is 318 head porting for the average joe, and most average joe's probably aren't gonna do any porting, but this thread was designed to hopefully encourage a few to do so, most guys doing a 318 are just doing RV cam, 4bbl and maybe headers. And the few that are taking it to the 325-425+ hp range have to get there with their abilities and what parts are available to them. Generally means stock or ootb parts. And for most it's cheaper and easier to build inefficient power, the low hanging fruit.
 
This ain't a pro engine building site,
Not everyone running 11's with a small port 308 is a pro engine builder. Quite the opposite. But by all means stay where you are.
The title of this thread is 318 head porting for the average joe,
Have you ever ported a cylinder head let alone 318 heads?
 
Here maybe you need to hear it from some one else:

This 318 head will out perform a 340/360 head, give snappier throttle response and mileage because the air is moving quicker to atomize the fuel for a better more complete burn for more power.
 
Not everyone running 11's with a small port 308 is a pro engine builder. Quite the opposite. But by all means stay where you are.
It's not about staying where your/I'm at, I don't know if you notice but most asking for build advice especially for 318 are generally novist and Super Stock, F.A.S.T, Pro Stock, Sprint Car, Nascar info and mods might be a little above their pay grade while they're trying to figure out which RV cam to run, most that know what their doing here basically document their builds here.
Have you ever ported a cylinder head let alone 318 heads?
No I haven't, I've mostly done the 340/360 top end on a 318 with 340 type cams in the past, right now I got the Mopar 380 hp crate engine.

Kind of my point when people/novist are looking to make more than a stock 318 head can provide and their more than likely not gonna port saying all these racers can do a lot more with similar size head ain't really helpful to most.
 
Here maybe you need to hear it from some one else:
Quoting him to me ain't gonna help your case lol, I have zero interest what that a$$ thinks, your way smarter then him, you don't need to quote him to make a case :)
 
That's funny a lot of local guys run 11's with less cubes (308 CI) with a head of similar size in street cars.

As a matter of fact some one will sell you an engine (308 CI) with a mild cam and stock valves sizes similar to a 273 that will run 11's.

These engines are designed for the budget minded who are looking for a low maintenance efficient engine that they can use in their everyday driver, but still drive to the track and run a mid to high 11 second ¼ @ 112-115mph with 3,000 rpm convertor and 3.5 gearing.
Who , what , where ?
 
Here maybe you need to hear it from some one else:

The problem with this guy is his knowledge is only around what he reads here and sees on TV or reads in a magazine. While good information can be had at such places, he is limited.
He cries a river after getting roasted and tries to for a conversation twisting & bending the words to suite his point of so called knowledge and the. Tries to rip you and your ideas as nonsense or done by a super secret pro that won’t tell anybody anything because there on double secret probation and will loose there tools if they speak out.

He is an idiot, no nothing, clean finger nailed geek that has t done anything except change his oil and replace spark plugs that were fouled to high heaven from his tuning skills.


He will admit this on occasion. So look out for this.

I have spent a ton of time correcting him which turned me into a bully by his account. Then I just spent time calling him out and still correct him over and over and over again to the point that this jackass is the only one I have on ignore temporarily. Temporary only since I can’t in good conscience let his stupid *** advice effect and/r ruin someone else’s build turning there engine into a pile of slow *** ****.

I wonder sometimes if I built more engines than he changed spark plugs.

I know he has built exactly the same amount of engines that I have changed plugs on my 5 cars in the last 5 years.

ZERO!

Don’t waste your time with guy. Just shoot the fish in the Dixie cup and move on. My words don’t seem to me **** to him and that’s fine even though there sometimes that same words or things I have figured out on my own that mirror what other well known people have figured out.

And I’ll tell you straight up I don’t know ****. But what **** I do know I’ll tell you straight up. But he’ll argue with me against what I have found and what the pro’s do.

By default, that makes me extraordinary or the pros dumb as ****. I say I wish I had the time and money to become extraordinary. But those are the guys I listen to. The been there and done that and still doing that with factual, repeatable and reliable results.

This guys argues there achievements or blows them off or states there super pro builder that we can’t replicate unless you dump a kings random to have done for you.

He is tiring.
 
It's not about staying where your/I'm at, I don't know if you notice but most asking for build advice especially for 318 are generally novist and Super Stock, F.A.S.T, Pro Stock, Sprint Car, Nascar info and mods might be a little above their pay grade while they're trying to figure out which RV cam to run, most that know what their doing here basically document their builds here.
You are giving advice that contradicts the title of the thread.

No I haven't,
That figures. When you have and have seen results contrary to what people here say and repeat ad nauseum because they don't actually know. Its not hard to get a 318 head over 200 cfm and I have a set over 240 cfm that I ported myself. 200 cfm is plenty for an engine up to 400 HP.

Go put a ported 318 head on a 360 and see how that performs.....It may actually shock you.
 
You are giving advice that contradicts the title of the thread.


That figures. When you have and have seen results contrary to what people here say and repeat ad nauseum because they don't actually know. Its not hard to get a 318 head over 200 cfm and I have a set over 240 cfm that I ported myself. 200 cfm is plenty for an engine up to 400 HP.

Go put a ported 318 head on a 360 and see how that performs.....It may actually shock you.
In his head, you can’t or your lucky to make more than 2hp per cfm of head flow like it’s a barrier that only pros can make.

It takes knowledge of which he just doesn’t lack but has a massive void over and proves it in arguments each and every time.

He is giving perfect examples of it right now. But he won’t believe you.
 
Quoting him to me ain't gonna help your case lol, I have zero interest what that a$$ thinks, your way smarter then him, you don't need to quote him to make a case :)
Sometimes even a blind squirrel finds a nut. Go and think about that sentence and figure out where your blind spot is.

I'll leave you with this: Just because a head flows 250 cfm that doesn't mean that is what the engine uses.
 
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