AJ's Opinion; Just for you 318 streeters

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I'll give you that, but the big port heads don't do much for you either until the rpm gets up, and then the stock cam chokes up.
So then to take advantage of those heads, you gotta jump the cam up. If you choose the 268/276/114, 340 cam, with no other changes, that is an instant recipe for a weak bottom end. With no rear gear change either, the power LOSS at low rpms will offset the subtle power increase over the top, and with a speed limit of 65mph, I lost performance every time I did it, cuz when she hit second gear the engine was way off the cam; hopelessly drowning in sucked out territory.
But yeah with 4.30s and a 2800, things picked up some. But 4.30s were lousy on the hiway.

I got way more performance by bolting all the 318 stuff including the cam, onto a 340.
I think your interpretation of what folks are saying might not be accurate. I don't think anyone is arguing that a 318 is a quicker, faster engine choice over a 340 or 360, or 440. I think what is being stated is if a person has a 318 and wants to "biff it up" a bit, by all means do it. And, it can be mildly done with improvements on bottom end torque as well as top RPM. It's precisely why I did the low dollar 318 build 5 years ago. I threw UNDER 500 bucks at a 318 2bbl, no headers, 2.76 gears and ran BETTER than a factory '73 340 Duster with 3.21's. IF this is what a person is shooting for, what's wrong with it??? I since sold the 4bbl/intake and replaced it with dual quads, so now it's 750 dollar motor. Guess what? I'll race any stone-stock 340 3.23 car. Maybe I win, maybe I lose, but I didn't pay 1200 bucks for a core long block either.
 
Interesting stuff
yeah I'll bite
Above I had a 318 example with a 262* cam in an 8/1 engine having 535cc of Effective swept.
Lets see if I can match that with a 360. To get that, the effective stroke would need to be 2.598
Lets see, Hyup I get 360 cubes/800ft/ Effective stroke of 2.60@ 71.5* Intake closing angle, and check it out same VP of 99@ Scr of 8.9
So now, as to bottom end, these two are both operating as 261 cubers would at 100% stroke useage. And as you can imagine, with VPs of just 99 for both, both are dogs at low rpm, and in identical cars, will be identically doggy until that big cam in the 360 wakes up. I mean 71.5* is up there in the 284 to 288 range.
 
Just a quick mention in why and how good a purchase of a OD trans is a good thing no matter what kind of engine you build is the gear spread and final drive ratio you get when you multiply the rear end gear by the OD ratio. Once you find the cruise rpm at what ever speed you want it to be at, you can work the engine cam question in reverse with the above numbers. In an example, instead of being stuck as you would say with 4.30’s as a final drive ratio, you could re-cam the engine for the final drive ratio and so very well. With or without the big cam.

The purchase of a Chrysler OD trans w/converter will knit require a shortening of the driveshaft and ether purchasing a trans Mount or fabbing one up yourself.
The cost of wires and a OD on/off switch is peanuts.
You guys crack me up.
 
Interesting stuff....it made me think of the a video UTG did about a year ago called "the myth of displacement" or some such. Anyone know how to post a link? It ties right into this discussion
In today's world, as you well know, you don't have to go big to go fast. If available and pain free, I'll take more cubes. But it's amazing what some of these small cube motors are doing.
 
Ok let me repeat;
I am not a 318 hater.
I'm gonna tell you how it is, and you decide for yourselves.
On the street,

hi-rpm power means almost nothing because on the way to 60/65 mph,you only pass thru the power-peak once.
But, the vast majority of the time, a streeter is between idle and less than 4000rpm, and usually at Part Throttle.
Cylinder pressure makes heat, and heat is power.
More cylinder volume when the intake valve closes, at a higher pressure, makes more power, and specifically more low-rpm power; and it can be measured and quantified as V/P. Read about V/P here V/P Index Calculation
Here is my opinion of V/P, on the street;
160 or more is overkill with plenty of tire-frying
140 is a fun number
130 is about the min. for street-fun, barely chirps skinny tires with streeter type gears
120 is way too weak for me
110 is atrocious
100 super lo-performance.
What does it mean?
well, at 800ft;
the '73 8/1 smoggerteen comes in at about 110V/P
the '69 hi-C, 9.0 rated 318 comes in at about 129VP
the 8/1 318 with a 340 cam, 84VP

the 10.5 340,........... at about 128
the 8.5 340 at ........................ 97
the 8.5 360 4bbl, at about ..... 104
the 8.0 360 2bbl at ............... 122
So that gives you something to think about. As you can see, the 318 has both the lowest and the highest in this ranking.
So what is it that makes this possible?
Answer; this is a two-parter;
1) Effective cylinder size when compression begins, and
2) the Effective Dcr.
The 8/1 318 with a 2bbl cam has a mathematical cylinder volume of 652.27cc
but by the time the intake closes, the Effective stroke is down to 2.86 inches, so... the Effective cylinder volume is down to 562.7cc, and the Scr of 8/1 has dropped to an Effective Dcr of 6.88
Now, hear this; Any engine no matter it's size, that produces the same or similar VPs, will, at the lower rpms (up to about 3000rpm), have similar performance.
>lemmee show you;
69 440Magnum 134VP/ Effective stroke 2.58/ E-volume of 620cc @ 7.38 E-Dcr
69 318 / VP of 132 / Effective stroke of 2.86/ E-volume of.. 563cc @7.74 E-Dcr
69 340 / VP of 128/ Effective stroke 2.52/ E-volume of ..... 529cc @ 8.06 E-Dcr
So as you can see, the Effective numbers are all over the place. Yet the VPs are very similar. Try this; take the volume and divide it by the E-Dcr.
the 440 comes to ........ 84.0,
The early 318 comes to 72.7
and the 340 to ............ 65.7
Notice the similar progressions.
>Now, as a 318 owner, you already know what the bottom end of your engine feels like. Lemmee show you what happens to it with a bigger cam;
'73 318 at 8/1, VP of 110, Ica of 50*
at 54*Ica, VP drops to 104
at 58*Ica, VP drops to 97, 273 sized
at 62*Ica, VP drops to 91
at 66*Ica, VP drops to 84, slanty sized
Each of these Ica's represents about one cam size. Notice how fast the VP plummets.
Next;
lets raise the compression by .4 per step with the 318 2bbl cam (50* Ica),and see what happens;
the '73 8/1 smoggerteen comes in at about 110V/P;
at 8.4 the VP climbs to 118
at 8.8 to 125
at 9.2 to 133 target minimum reached
at 9.6 to 141 fun target reached
at 10.0 to 148
at 10.4 to 156, tire-fryer
You see how FAST the VP climbs?

So now we have seen how the Ica affects the VP in an 8/1 engine, and also how the VP climbs with Scr. Now lets see what happens when we add cubic inches to an 8/1 engine, while keeping the Ica at 50*
the 273 would start out at......................... 95VP
the '73 8/1 smoggerteen comes in at about 110V/P
the 340 would come in at 118VP
the 360 at...................... 126VP
the 408 at...................... 143VP
Wow! look at how those numbers jump!
And how about elevation?
the '73 8/1 smoggerteen comes in at about 110V/P @ 800ft
By 1600 it has dropped to 107.
By 2400 to 104
by 3200 to 100
by 5000 to 93, back in slanty territory.

But of course no sane 318 owner, when contemplating performance, desires to keep the cam stock. Why? Aye there's the rub. Cuz they all want their engines to have that big cam sound, right.
But as I have shown you, that later-closing intake valve, drives the Dcr right into the basement, and low-rpm performance, right along with it.I mean look at the 318 with the 340 cam above; the 8/1 318 with a 340 cam, 84VP. 84 is slanty territory! Do you really want your burbling 318 to take off with slanty performance?
So there you go, you decide.

Each one size bigger cam, with NO OTHER changes, will move the top of the powerband up about 200rpm. While also moving the Torque-peak up a similar amount, and the bottom end torque falls away easily half that, because of the loss of cylinder pressure/VP.
Going from a 318 cam of 50* Ica to just two sizes bigger, say 58*Ica, will move the power from about 4200 to 4600. That 400rpm is where the power comes from. Say you had 280 ftlbs at 4200= 224 hp. Now say you moved that 280 up to 4600; the new power would be 245 hp sounds sweet right. But what about the power loss at say 2000 stall? That's gonna hurt. And there is only one way to get it back,namely more pressure/more VP.
Now, you can work around it with a higher stall, and or a bigger rear gear. But those carry other downsides. And they do not address the fact that the low Dcr is affecting the power of your engine all the way from stall to shift rpm. AND by the time you pay somebody to install the TC and gears, you could have fixed the problem by one of the other three ways namely; cylinder pressure, Ica, or cubes.
You decide...............

Now, for Performance, here are the yardsticks I use;
10 pounds per horsepower/ 1.0hp per cubic inch.
why?
well, cuz these numbers make for a fun car. By the time you get to 12 pounds per cubic inch, at 1.0 hp per cube, maintaining the performance is gonna take gears and stall. Pretty soon the car is no longer a DD and no longer a dual-purpose machine. So it sits in the carport 6 days out of seven, with the gas going stale, and the brake rotors rusting, and the tires rotting. Time goes by and you realize that, you almost never drive it any more. But you got 20/30G stuck in it, which you will never get out of it. Then one day you hit the starter, and three valves are stuck in the guides, and that's that.
So, by my yardstick, a 318 is fine in a race-ready 3180 pound car at 318 horsepower. That will be a lot of fun at 800 ft elevation. The same amount of fun as a 360/360hp in a 3600 pound car. Or a 4400 pound pick-up with a 440/440hp.
I don't hate the 318
It's just hard to find a 3180 race-weight chassis, me in it. and
building a 318/318hp is NOT cheap nor easy.
You decide.
Why does it have to be 318/318 hp?
Cuz if Ima gonna spend all my hard earned cash, I don't want no slouch engine. And I don't want to do it twice or three times anymore.
1.0 hp per cube is a fairly realistic and easy target to attain.The engine is street friendly if a lil hard on gas. After that it starts getting expensive, and
by 1.1 it's getting harder/ pricier, especially with the smaller, small-blocks..
By 1.2 the engine is or has, leaving/left streetability behind.
By 1.3, honestly, give your head a shake, you shouldda started with a bigger engine.
You decide.
I tried to keep my bias out of this as best as I could.
 
Well I don't know about anyone else but I found this thread a wealth of information from some very knowledgeable A-Body members! Me, I'm willing to bet, I am like a lot of members on here and don't have the technical knowledge of these posters, AJ, Yellow Rose, Rumble fish , 318 , but I'm sure glad to have your experience to draw from. You all have different opinions and that's cool. Please keep up the very informative posts. There's a lot more of us watching and learning than you may know.
This what makes a good community in my humble opinion.

Cheers guys !
 
But of course no sane 318 owner, when contemplating performance, desires to keep the cam stock. Why? Aye there's the rub. Cuz they all want their engines to have that big cam sound, right.

Ok so a certain someone construed this to mean something I did not say. So let me re-word it for you.
The sane 318 owner, when contemplating performance, does NOT desire a stock cam; but rather, wants to have a cam with a bit of lope; right.
In other words, for performance, would it be sane to contemplate a stock cam.
Com'on Rumble, this is NOT a foreign language. Com'on Rumble, admit it; you saw the words "no sane 318 owner" in your skimming, and your brain got stuck there.
 
yada yada yada, my thread, my opinion, and go start your own thread, yur plugging mine up.
NO worries hater. I agree a bigger engine to start with is a good idea. I’m just trying to help those that want to hop up there 318, unlike yourself that pours hate on them small engines.
Interesting stuff....it made me think of the a video UTG did about a year ago called "the myth of displacement" or some such. Anyone know how to post a link? It ties right into this discussion
What UTG did is what AJ is explaining and why a bigger engine is better to do in a scientific manor. AJ gives outright good advice, except when he throws you under the bus for doing a 318.
yeah I'll bite
Above I had a 318 example with a 262* cam in an 8/1 engine having 535cc of Effective swept.
Lets see if I can match that with a 360. To get that, the effective stroke would need to be 2.598
Lets see, Hyup I get 360 cubes/800ft/ Effective stroke of 2.60@ 71.5* Intake closing angle, and check it out same VP of 99@ Scr of 8.9
So now, as to bottom end, these two are both operating as 261 cubers would at 100% stroke useage. And as you can imagine, with VPs of just 99 for both, both are dogs at low rpm, and in identical cars, will be identically doggy until that big cam in the 360 wakes up. I mean 71.5* is up there in the 284 to 288 range.
284/288 is a sizable camshaft in most every catalog. Not something I’d use in a streeter for everyday.
You guys crack me up.
Thanks you.
I also have a picture of AJ framed on my wall.
:lol:

Well I don't know about anyone else but I found this thread a wealth of information from some very knowledgeable A-Body members! Me, I'm willing to bet, I am like a lot of members on here and don't have the technical knowledge of these posters, AJ, Yellow Rose, Rumble fish , 318 , but I'm sure glad to have your experience to draw from. You all have different opinions and that's cool. Please keep up the very informative posts. There's a lot more of us watching and learning than you may know.
This what makes a good community in my humble opinion.

Cheers guys !

Will do! I hope to help every small displacement guy that comes aboard looking for help without saying get a 340/360.

When a member comes on and says he has a 318 he wants to hop up, I try and answer them for there engine. I point to 318willrun pretty quick to! He is active on his you tube. (Maybe one day I’ll do one…lol!)

I started a thread over a decade ago on hopping up a 318. Things got in the way and the car had to go. I wanted to show a few things you could do and why somethings work better than others. It was fun for the short time I had it.
 
Willrun
I understand what you are saying, But if you can 60ft that at 2.1 I think I'll dynomite my car to smithereens,lol. If it doesn't spin,Ima thinking you'll be measuring the 60 ft with a sundial. If it spins just one wheel, you'll probably be a bit quicker.
And then there is the small matter of "fine". But I know that's subjective, so I'll try to leave it alone.

Staaaaaand back !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
AJ/FormS is learning how to use dynamite to uphold his word........ (read post 27)


AJ, back a few days when we were having fun... remember??? LOL. This is why formula's that explode ones mind is not always where I bank my bucks. So many are impressed with a long list of formulas and say wow. I know it's your MO, but I'm glad I have A.D.D. when it comes to reading, cuz' my car can't read either so neither one of us know how fast (or Slow...) we are supposed to go. :poke:
 
NO worries hater. I agree a bigger engine to start with is a good idea. I’m just trying to help those that want to hop up there 318, unlike yourself that pours hate on them small engines.

What UTG did is what AJ is explaining and why a bigger engine is better to do in a scientific manor. AJ gives outright good advice, except when he throws you under the bus for doing a 318.

284/288 is a sizable camshaft in most every catalog. Not something I’d use in a streeter for everyday.

Thanks you.
I also have a picture of AJ framed on my wall.
:lol:



Will do! I hope to help every small displacement guy that comes aboard looking for help without saying get a 340/360.

When a member comes on and says he has a 318 he wants to hop up, I try and answer them for there engine. I point to 318willrun pretty quick to! He is active on his you tube. (Maybe one day I’ll do one…lol!)

I started a thread over a decade ago on hopping up a 318. Things got in the way and the car had to go. I wanted to show a few things you could do and why somethings work better than others. It was fun for the short time I had it.
Hey, I want AJ to keep ragging on the 318's so the price stays down!
 
Com'on Rumble, admit it; you saw the words "no sane 318 owner" in your skimming, and your brain got stuck there.
I won’t admit that but I will explain that after doing union rep work and dealing with highly educated to zero education peoples from a relatively wide upbringing and social status, points of view and understanding can be drastic. How people take what you right can be wide and varied. There actions based on your words and assumed credibility could be catastrophic. This is why I centered in on that.

You constantly down the smaller engines.
You consistently do not help the member looking for help on anything but what you prescribe as your engine in what almost seems to be, but never said, though pushed as the ultimate street engine. And boy o big do you brag on about it as if it were!!!!!!
 
Wow after having read this and owned no less than a dozen 318's in all types of configurations over the years and ran them all over the country, which all performed well and where extremely reliable. I now wonder how I could have ever owned and built such a small weak
engine...oh well time to build to build $$$ HUGE stroker and race nobody then drive to the local drag strip thats closed.
 
Interesting stuff....it made me think of the a video UTG did about a year ago called "the myth of displacement" or some such. Anyone know how to post a link? It ties right into this discussion
You cut and paste the URL. Thats the address at the top of the page. That is the link.
 
My 273 bracket racer ran best of 12.72 with stock heads, and never broke out of low 13's with 2.02 valve 340 heads (probably a loss of compression for one thing).
Dib’s. I think you made a typo since a 2.02/1.60 configuration doesn’t fit a 273. Or your 318, not a 273….
 
My 273 bracket racer ran best of 12.72 with stock heads, and never broke out of low 13's with 2.02 valve 340 heads (probably a loss of compression for one thing).
273 is not a 318 ....
 
Ok let me repeat;


But you apply YOUR definition of “street” to everything. What you call street I consider pretty milquetoast.

For me, “street” can encompass a whole lot more that what you limit it to. I have driven 4.56 gears on the street since I traded my 498 cased 3.23 Trac-lock diff and a hurst shifter handle for a 742 cased 4.56 Powr-lock diff in the fall of 1980. I drove that thing everywhere. Even down the freeway to the beach and I let it RPM. If the GF started bitching about it, I’d pull over and tell her to wait there and I’d pick her up in two days. That stopped most of that sniveling.

And that’s the crux of the issue. You live and die by your definition of street. I have been doing what people say Isn’t street since 1980. That includes tunnel rams and other stuff. In fact, my 340 will have a tunnel ram this year, and the W2 Stroker deal will have a Holley Pro Dominator tunnel ram on it. And I’ll drive them on the street with 4.88’s and I’ll have the wife drive it to prove how easy it is.

Oh, and that’s with a clutch that most everyone claims is a drag race only clutch. And it the D60 will have a spool.

My definition of street is not the same as some other folks.
 
To me there’s two main ways of looking at a combo you want build and reality it’s usually a combo of the two.

1st build to a certain powerband say a streetable 1000-5000 rpm with peak hp at 5000 rpm. Which if done right should be around 1 hp per cid. Obviously if you do a 273/318/340/360/408 the combos are gonna be vastly different from one another mainly head flow since 273 needs less head flow than a 408 to make 1:1 hp:cid. So obviously the bigger the engine the more power, this is how the factory muscle cars did it.
This way the combo and hp very but the powerband is basically the same.

2nd is to build to a certain performance level aka hp #. Say like 400 hp now the combos will be more similar like 200-220 cfm heads around 10:1 cr and 275-285 ish cam etc.. so combo and hp are now similar but powerband is veried same with gearing and stall which to me is the main problem since most only want to run 3.55 ish gears.

So yes a 360 in practically all cases should be the choice to build over 273/318, I could also easily make that argument for a 440 since it’s the largest readily available engine. Most are not looking to get every last hp et/mph out of there combo.

When helping people it’s not necessary what you would do but what you would do if you had their wants and skill money etc...

Most 318 peeps just want 4bbl duals maybe headers and a decent cam and lot on here make it near impossible to do so. Most are not looking to build a 500hp 318 monster. They just want to burn a little rubber and have a little rumble.
 
Page after page after page of why NOT to build a 318, yet still no one will recommend a "one step up" hydraulic flat tappet cam that doesn't kill the low end or MPG.

Perhaps we should concentrate on improving 0-60 times rather than increasing HP.

That sounds like a reasonable goal for a street car to me.
 
Page after page after page of why NOT to build a 318, yet still no one will recommend a "one step up" hydraulic flat tappet cam that doesn't kill the low end or MPG.

Perhaps we should concentrate on improving 0-60 times rather than increasing HP.

That sounds like a reasonable goal for a street car to me.


Problem with one cam recommendation is 1 nobody is gonna agree on one cam, plus everyone has a different level of compromise, but I agree 0-60 is what most street guys should focus on, which is mainly what Aj long windedly goes on about :)
 
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Page after page after page of why NOT to build a 318, yet still no one will recommend a "one step up" hydraulic flat tappet cam that doesn't kill the low end or MPG.

Perhaps we should concentrate on improving 0-60 times rather than increasing HP.

That sounds like a reasonable goal for a street car to me.
318 Hughes Whiplash cam
 
Need a light A body? Come talk the wife out of her 62 Lancer! I tell her it is as ugly as a mud fence, she just tells me it is unique and has character!! ha
Sorry to interrupt the discussion! Back to the channel!
 
Page after page after page of why NOT to build a 318, yet still no one will recommend a "one step up" hydraulic flat tappet cam that doesn't kill the low end or MPG.

Perhaps we should concentrate on improving 0-60 times rather than increasing HP.
Once you move away from the stock cam, mileage bets are off. Anyone who can tune a distributor and carb can lick 99.9999% of mileage issues.
Any HFT duration of 218 and lower.
No converter change needed.
 
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