Big horsepower 318 builds

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I have no problem with the ability of a 318 producing 500 HP. NA
But I believe it would be in the 7000 or so rpm range. Going to have to spin it.


I’m trying to get my head around why you think 7000 RPM is in the RPM stratosphere. It’s not. That is STREET/Strip RPM.


It’s not 1972 anymore.

And we have guys arguing that 500 HP in the dyno is useless, and others arguing that the engine in the article is some high dollar, exotic double and quadruple the cost of a stroker. That’s just stupid.

We have guys arguing that airflow isn’t everything (it’s not) but to swing the discussion over to the stupid limits of Stock, Super Stock and now this Factory Stock stuff is just pure mental masturbation.

No one with the IQ of a grape who isn’t building a SS legal engine would EVER pay to have a set of heads done like that. That is the definition of RETARDED.

Now we are just arguing for the sake of arguing, arguing about nonexistent numbers, and then backslapping each other and yourselves thinking you’ve made your point, when in reality, you’ve proved nothing.

You can’t build a 500 HP 318 that doesn’t spin to 10,000 RPM and have a set of 15k heads on it.

There, the argument is settled.
 
Some on this thread feel the air flow is the only thing that matters in making power.
If that’s the case, then a 318 should be able to do it with bowl blended J heads.
My 383 made 504hp on the dyno with unported 906’s that flowed 235cfm.

The Wallace calculator seems to agree it was 500hp.

View attachment 1715579054

It's not the only thing but makes it easier, why modern LS, Hemi even Magnum and 340 used way more head flow than needed to make more streetable power than camming up and super high CR to squeeze hp from a lesser head.

Air flow is everything....... like the 220cfm heads(and the .420 net lift at the valve cam) on the motor powering this car......

View attachment 1715579058

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Oh yeh, stock iron intake and a Q-Jet too.

Yes more than one way to skin a cat, awesome engineering.

Nor do I....... it’s just not going to be something you can throw together like you could with a 408 that had several of the components being far from optimized, and still end up making the 500hp.

This is a cast crank, flat top piston 416(12:1) with an easy on parts flat tappet cam and bowl ported RPM heads.
Knock the CR down to a pump gas friendly 10.5:1, take some duration out of the cam, but crank up the ramp speed a bit...... still would be very solidly over 500hp.

View attachment 1715579065

The thread is Big power 318's not is 318 the best way to make big power.
I wouldn't do a 500 hp NA 318 or any small block for that matter, Big Block would be the way I'd go, But If someone wants to build a /6 273 318 or whatever and they know the short coming of that decision then I'm all for it and want to help them to reach their goal even if it's not the way I'd go.
 
I’m trying to get my head around why you think 7000 RPM is in the RPM stratosphere. It’s not. That is STREET/Strip RPM.


It’s not 1972 anymore.

And we have guys arguing that 500 HP in the dyno is useless, and others arguing that the engine in the article is some high dollar, exotic double and quadruple the cost of a stroker. That’s just stupid.

We have guys arguing that airflow isn’t everything (it’s not) but to swing the discussion over to the stupid limits of Stock, Super Stock and now this Factory Stock stuff is just pure mental masturbation.

No one with the IQ of a grape who isn’t building a SS legal engine would EVER pay to have a set of heads done like that. That is the definition of RETARDED.

Now we are just arguing for the sake of arguing, arguing about nonexistent numbers, and then backslapping each other and yourselves thinking you’ve made your point, when in reality, you’ve proved nothing.

You can’t build a 500 HP 318 that doesn’t spin to 10,000 RPM and have a set of 15k heads on it.

There, the argument is settled.
Like I said, I'm looking forward to your dyno results.
It was you that turns your street 340 8000 rpm's. why ?
 
What I’m seeing in the Ford/Chevy 302 video is....... two motors with way higher flowing fully ported heads(345cfm with 2.19 valves for the Ford/311cfm and 2.08 valves for the Chevy) that have bigger valves in them, making less power than the 416 I posted the dyno sheet to.
Those 416 heads have 2.02 valves and flowed about 270.

The test with the Chevy and the TR that made 545hp was also done using Q16 fuel.

Here’s a street/strip 410 , 270cfm heads, 2.02 valves, smaller cam than what was used in the video motors, running on pump 93, run with the crank turning the water pump.
(Electric water pumps on both the video motors)

A73BA0B5-BF1F-4117-9EC7-A08A042BD9C1.jpeg


273’s always arguing how the cubes don’t matter.
My experience is they do.

There is no doubt in my mind that a 318 built using the equivalent parts on it as was used for either of the motors in the video, that you’d end up over 500hp.
(If you used TF heads for the 318, you’d still have smaller heads, with smaller valves, flowing less air than either of those video motors)

And I’m also just as sure that if those same parts were on a 416...... it would be over 600hp(at least it would be if I built it).
 
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The article on the 477hp 318 states the heads were ex-SS heads.

If they were competitive SS heads, I could build a whole 500hp 408 for what those heads would cost.

You take the top end and cam off a 500hp 408, and put them on a 318 of the same CR....... you’re not going to end up with 500hp.

The 500hp 408 can be built by ordering pretty much the entire motor from the Summit catalog.
Deck/bore/hone the block, prep some heads, blend the bowls, an off the shelf cam from some catalog, bolt it together.....10.5:1, pump gas.......500hp.
I was making the same point about those heads and it seemed to dust right over everybody's head but hopefully having a guru make the point the same one we'll have some validity...
 
The only way to have a thread of this topic is to build it without saying a word, then post it and the numbers. You cannot say "I'm building a 500 hp 318", I've learned that don't work. LOL. You have to silently do it, then post it :)
 
I was making the same point about those heads and it seemed to dust right over everybody's head but hopefully having a guru make the point the same one we'll have some validity...


Actually, if you read what I posted about those heads it would have saved you a lot of grief.

They used those heads because they HAD them (according to the article anyway) and it was a poor choice for heads unless you already had them.

The author of the article SHOULD have pointed that out.
 
The only way to have a thread of this topic is to build it without saying a word, then post it and the numbers. You cannot say "I'm building a 500 hp 318", I've learned that don't work. LOL. You have to silently do it, then post it :)


It won’t matter. As soon as you post the results, all the track guys will start vomiting out the boring old saw that “we don’t race Dyno’s” like they always do.

Of course, we don’t race micrometers and torque wrenches either, but we use them.
 
It won’t matter. As soon as you post the results, all the track guys will start vomiting out the boring old saw that “we don’t race Dyno’s” like they always do.

Of course, we don’t race micrometers and torque wrenches either, but we use them.
You dyno'd 501 hp and ran a 10.86..... but was there a tail wind... :D
 
The only way to have a thread of this topic is to build it without saying a word, then post it and the numbers. You cannot say "I'm building a 500 hp 318", I've learned that don't work. LOL. You have to silently do it, then post it :)
Like 10's on 5k... Bahahaha...
 
Actually, if you read what I posted about those heads it would have saved you a lot of grief.

They used those heads because they HAD them (according to the article anyway) and it was a poor choice for heads unless you already had them.

The author of the article SHOULD have pointed that out.
As I read it they shot after them because they were so great and in order to get them they had to go through a friend of a friend meaning they had to be in the know to get them...
Oh yeah and don't forget....
Screenshot_20200816-095722.png

Take your meds...:poke:...:D...
 
Actually, if you read what I posted about those heads it would have saved you a lot of grief.

They used those heads because they HAD them (according to the article anyway) and it was a poor choice for heads unless you already had them.

The author of the article SHOULD have pointed that out.

So..... you’re building an engine specifically to use in an engine dyno competition ....... and just throw any old head on it because you have them kicking around.
Yeh, I believe that.

If they didn’t feel those heads were fully up to the job...... they would have used something else.

They coulda/woulda/shoulda used other heads..... blah blah blah.
The bottom line is...... the heads they actually used would have had a ton of work done to them, and would have flowed very very well for their port cross section and runner volume(ss rules).

Imo, they would have had a pretty high impact on that overall package, and that just replacing them with some typical ported EQ Head would have almost certainly resulted in less power on that particular combo.
I feel they were a key component of the success of that package.

The person the engine builder contacted about heads was Randy Malik, who has been entering those EM contests since the beginning, often doing pretty well.
So, I’d expect him to have a good handle on what it would take for cylinder heads on the 318 build to be competitive.
I doubt he would have recommended that particular pair of heads unless he felt they would have been a good fit with the rest of the combo.
 
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273’s always arguing how the cubes don’t matter.
My experience is they do.

I do and don't, I think people over simplify by using torque is king and no replacement for displacement mantras.
And don't put too much value in rpm and gearing also, rpm got equal billing in the Hp formula for a reason torque x rpm / 5252 = hp.
Sometimes this train of thought of "torque is king and no replacement for displacement" leads to bad and or faulty decisions.

I go by the theory that the bore is the ultimate limit of NA power if taken out to the limits, eg. 4.04" bore 340 vs 410 at say piston speed of 5000 fpm so 9063 rpm vs 7500 rpm if both engine are built to take full advantage of the bore size and rpm they should come up with similar hp peaks and curves and the 340 should have a slight advantage cause of friction and better rod ratios. Now in everyday average build I could see the 410 coming out on top most of the time but I don't think it's safe to assume it's an always the case people make it out as, all the builds I've read and watch they use pretty similar parts for similar output no matter what engine make or size.
 
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My view is simpler than that.

In “most” cases, it’s easier to get the larger motor to “use up” the cylinder heads.
In that video, they put 345cfm heads on a 302 and never even got close to using up the available flow.
On my old 451, I made about 170hp more than that motor did out of my 340cfm heads with 2.19 valves(without a ported manifold like the Ford had).
And on another build that was yet another 106 cubes...... with slightly lesser flowing heads of the same type as what I had on the 451....... it made another 70hp.

So that motor made 235hp more than that 302 did, using heads that flowed 337cfm, and didn’t have the benefit of a ported intake manifold.

Using some simple formulas...... it would take the 302 nearly 11,000 rpm to use up a set of 345cfm heads.
On a 451 it takes 7300rpm...... which is much more within reach for most builds.

The old SuperFlow formulas show the 270cfm heads are capable of 555hp......... and that on 416ci....... they would peak around 6200(made 561@6300).
The same formulas say it would take 8000 to use them up at 323”.

The 311cfm heads on the 302 Chevy are worth 640hp.
To use them up on a 302 would take 9850rpm........ but 7330rpm would do it with a 406.

In the 30 years I’ve been dyno testing motors....... I have seen some motors follow formulas pretty well....... and others that just don’t.
But I don’t recall ever testing a small-ish cube combo, that fully exploited the potential of some large-ish, high flowing heads...... and could do it at a moderate rpm(NA).

To me, the fact that the TQ goes up as the engine gets bigger is usually just an added bonus.
 
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Do you know how many times I’ve been told my flow bench and dyno numbers are lies because the car doesn’t run what it should? Many, many times.

So you go to the track and watch the junk **** make a pass. The converter is wrong, not nearly enough gear, worn out tires, the car has never been on a scale, let alone corner scales, shocks I wouldn’t use on station wagon, front end tied down so the driver can “cut a light”, wheelie bars too low, ladder bars (if you can’t hook with a cal Trac type of bar you need a 4 link, of course the morons don’t want to learn a 4 link so the ignorance inertia goes forward), wheelie bars too high, IC set by the ladder bars or on a 4 link set by some magic percentage of the wheel base, can’t read a plug or use a timing light...

It goes on and on and on. So the time slips are NOT evident of much anything except can the tuner tune. Most times, the answer is no. So the dyno numbers aren’t wrong, it’s the junk car and/or ignorant tuner. But they dyno numbers take the fall for stupid.

As for the rest of your whittle little post, you didn’t question ****. How can you? I haven’t posted ANY numbers yet, but your mouth is on full blast. You are running your sewer about something that hasn’t even happened yet.

And you try and claim the high road. You can critique the dyno numbers AFTER they are posted not before. Do you see how idiotic you are being?

Grow up and act like a 59 year old man who actually has been to a track once or twice.

Who mentioned any dyno numbers you posted? I've never seen you post a dyno sheet, same with time slips.

A monkey should be able to tune a leaf spring chassis to run mid 10's. It's just not that hard.

So you don't think time slips are of any value? You don't think the mph indicates anything? Last weekend I made three passes, three very different passes. Pass #1 the car felt like it was hooking and unloading, it did this about four or five times before it settled down. I tightened the rebound two clicks on the front shocks before pass #2. On pass 2 I decided to use the trans brake. When I applied the brake and came up on the two step the car bumped forward and red light, then blew the tires off on the hit, I peddled it twice before it hooked up. For pass #3 I tightened the rebound two clicks on the rear. Foot braking to 2k like pass 1, the car left straight and smooth and made a clean pass.

There was a big variance in the 60' and et between the three passes but it ran anywhere from 108.13 to 108.42 mph for the three. So if you were looking at the time slips would they tell you?

How about you grow up first and if I like what I see I'll give it a try.
 
Back to the subject of 500hp 318's? Unless you're running a stocker or a ci limited class why would you attempt it? 500hp is easy with a 360 block, a 4" crank, decent heads and a easy to live with cam. IMO it would be an all around more fun package to drive too. Plus in the long run it would probably be easier on the pocket book.

I do like to watch high hp short stroke small blocks run but have no interest to build one.
 
Here’s an example of the formulas not working out:
540” motor, heads flow 360.
Formulas say 740hp@6300.

Intake A 732hp@6400(pretty close)

Intake B 805hp@6800(hhhmmmm)

Intake C 848hp@7300(uh..... way off)

Tests done back to back, no other changes.

The problem with the formulas is...... not enough inputs.

Like I said previously........ if you built a 318 along the lines of what was in that video, it would be a slam dunk 500hp.
 
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The article on the 477hp 318 states the heads were ex-SS heads.

If they were competitive SS heads, I could build a whole 500hp 408 for what those heads would cost.

You take the top end and cam off a 500hp 408, and put them on a 318 of the same CR....... you’re not going to end up with 500hp.

The 500hp 408 can be built by ordering pretty much the entire motor from the Summit catalog.
Deck/bore/hone the block, prep some heads, blend the bowls, an off the shelf cam from some catalog, bolt it together.....10.5:1, pump gas.......500hp.

The guy who did those SM heads for me a couple of months ago....does Stock/Super Stock heads and engines...and he is expensive....He has a 360 Dakota that has 9.82 @ 135+ ...held or hold the National Record for the class...He said his SS heads only flowed 260 CFM.....but spins the engine upwards of 8500 rpm....
 
He said his SS heads only flowed 260 CFM

With a stock sized valve and a cc limit.
So, very high velocity and a high discharge coefficient.

Based on the ET/Speed he’s running.......those heads are obviously capable of supporting well over 500hp.
 
How about a discussion about a naturally aspirated, no nitrous, stock stroke, 318 on gas or alcohol. I have read quite a few posts lately about 500+ horse teens that I find hard to believe.

I watched Bob Mazzolini race his 318 years ago. Cast iron heads, low compression pistons, QJet carb. Made more than 500 hp, ran low 10's in a Sebring. Very high dollar engine with a high dollar transmission and a high dollar car. It would yank the front end and go. He used a cast crank since it was lighter. Not sure on the RPM, well north of 7K.

I think the compression ratio in Bob's engine was 8.9 and he used some 360 cast iron heads but I don't recall the part number. Car was around 3200 lb and it ran low 10's. When I saw Bob's car run it really woke me up to the fact that there is a big difference between what most people think and what is possible with some dedicated effort.
 
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When I saw Bob's car run it really woke me up to the fact that there is a big difference between what most people think and what is possible with some dedicated effort.
Your statement ^^ goes right along with what i posted in post 92. Smaller motors need more thought.
 
I watched Bob Mazzolini race his 318 years ago. Cast iron heads, low compression pistons, QJet carb. Made more than 500 hp, ran low 10's in a Sebring. Very high dollar engine with a high dollar transmission and a high dollar car. It would yank the front end and go. He used a cast crank since it was lighter. Not sure on the RPM, well north of 7K.

I think the compression ratio in Bob's engine was 8.9 and he used some 360 cast iron heads but I don't recall the part number. Car was around 3200 lb and it ran low 10's. When I saw Bob's car run it really woke me up to the fact that there is a big difference between what most people think and what is possible with some dedicated effort.
Yep! Wayne Taylor's Chrysler Sebring at NHRA World Finals
 
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