Is More Flow Better, Is The Smallest Intake Port That Flows The Most The Best

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Does a more efficient port improve cylinder fill on intake valve closing? Does a bigger valve and bigger runner increase reversion and does that hinder cylinder fill................
 
Your talking over my pay grade :) but I'll take a shot
Hysteric said:
Does a more efficient port improve cylinder fill
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I would say generally yes
Hysteric said:
on intake valve closing?
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Have no idea, what's the significance ?
Hysteric said:
Does a bigger valve and bigger runner increase reversion and does that hinder cylinder fill................
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bigger than optimal ?

Say runner/port opening is optimal size for target hp for the displacement rpm, since valve is the main restriction wouldn't enlarging the valve and opening the bowl to closer match the runner/port opening be more ideal ?
 
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If it doesn't fit ones narrative...he will think/talk around it.
There is such thing as too big but, we aren't talking about too big.. we are talking about properly sized here vs small as possible.
Example...Charlie's head goes turbulent after it's 'big performance'...because it is too small...in lamens terms..
Velocity is what we are after...but too much is too much...and it starts ripping from one side of the bowl to the other, blocking any flow increase to the point of flow loss.


I just mentioned this video set yesterday or the day before in the Dvmia318 thread and said it would make for a good opener of discussion in another thread .
Watch Chad spiers video now, 3 videos.
Target velocity ... know the territory.
Some here 'who only mention others accomplishments' get carried away with velocity/small port ideas and boast of ridiculous 318 power and 3.23 gears and 11's in the 1/4...but does anyone believe those claims from these people?
Have we seen any proof or even head work pics? Flow sheet ,time slip...anything? Nope!
So dont fall for arguing hypotheticals with bozos who are dancing in fantasy land. You want a port with enough cs, aka big enough for the airflow passing or it will be LESS than optimal, not more.
 
MOPAROFFICIAL said:
Target velocity ... know the territory.
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Totally agree. Have a think about what creates the demand for air to flow in the first place ie the piston speed and where the valve is in relation to that and also the vacuum generated at the valve curtain area and how that aids vaporization because liquids don't burn in cylinders gasses do. Funny how head porters never talk about combustion and how to improve it because all they understand is airflow. When you can't utilize the fuel and air you already give an engine give it more air........

I've posted many examples of engines that punch above their weight for the head size and airflow those engines receive. Imagine a 360 running to 6K with a 1.78 valve. As always you can highlight facts but people will always attack what they don't understand.

273 said:
Have no idea, what's the significance ?
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Is the cylinder still filling as the piston passes BDC and returns to TDC? Does that column of air and fuel have inertia and does it still continue to fill the cylinder until the valve closes?

All these things you need to think about if you want to build power. Here's a thought what happens with you put a much bigger head with a much bigger valve and a big manifold and a big carb on that same piston speed and demand generated? Ever thought about that?

Vacuum plays a big part in vaporizing the fuel so you can burn it so does all that increase in size help that or worsen that? Does the distillation temp of the fuel you use matter?

Now go and look at this engine and think about how the smaller carb ran the quickest, Idled the leanest while making 4.5 inches of vacuum at the top end.

How to Pick the Best Carburetor for a Street/Strip Car

There's more to making power than just airflow other wise the bigger carbs would have run quicker. Head Porters always talk about the air they never discuss the fuel.
 
What kinda flo is best? I like Linoleum. It's easy to keep clean.
 
Hysteric said:
Is the cylinder still filling as the piston passes BDC and returns to TDC? Does that column of air and fuel have inertia and does it still continue to fill the cylinder until the valve closes?
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I would think the column of air would be like a freight train hard to get going but once going hard to stop, if having problems filling as valve begins to close wouldn't that be the port choking it in some way ?
Hysteric said:
All these things you need to think about if you want to build power. Here's a thought what happens with you put a much bigger head with a much bigger valve and a big manifold and a big carb on that same piston speed and demand generated? Ever thought about that?
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Yes I have Sir :) the way I see things is I and most others is stuck with what's available ootb or stock heads in mainly stock form and to most street manners are generally important in various degrees, so for most people the question is what heads will allow me to accomplish my goals with the smallest cam within reason.

Eg. Say 360 hp 360 Is it a stock set of 302 with CR and duration cranked up or milder cammed eddy's which is the more streetable package ? Would it be better if we could optimize the port shape size per application yes of course, everything is a series of compromises, velocity is import but only one peice of the puzzle.
Bet more people have killed a lot of power over worrying about it and being ultra conservative in carb intake heads etc.. choices.
Hysteric said:
Vacuum plays a big part in vaporizing the fuel so you can burn it so does all that increase in size help that or worsen that?
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Increase over optimal ? And it's only optimal by putting some kind of restriction / goal like eg. 360 hp, cause say I have a zero decked 360 short block with say a xe285hl cam do I care about vaporizing the fuel when I go from stock 302 to trick flows when I just gained 100 + hp ? So if the goal is to build the best most efficient engine at a certain hp and or e.t. Etc.. I'm sure it does.
Hysteric said:
Does the distillation temp of the fuel you use matter?
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No idea
Hysteric said:
Now go and look at this engine and think about how the smaller carb ran the quickest, Idled the leanest while making 4.5 inches of vacuum at the top end.

How to Pick the Best Carburetor for a Street/Strip Car

There's more to making power than just airflow other wise the bigger carbs would have run quicker. Head Porters always talk about the air they never discuss the fuel.
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And for a different combo could of went the other way unfortunately lot things need to be tested and tuned if you want to dial your combo in to perfection. Same with stall gears intake cams might have to try a couple.
 
MOPAROFFICIAL said:
If it doesn't fit ones narrative...he will think/talk around it.
There is such thing as too big but, we aren't talking about too big.. we are talking about properly sized here vs small as possible.
Example...Charlie's head goes turbulent after it's 'big performance'...because it is too small...in lamens terms..
Velocity is what we are after...but too much is too much...and it starts ripping from one side of the bowl to the other, blocking any flow increase to the point of flow loss.


I just mentioned this video set yesterday or the day before in the Dvmia318 thread and said it would make for a good opener of discussion in another thread .
Watch Chad spiers video now, 3 videos.
Target velocity ... know the territory.
Some here 'who only mention others accomplishments' get carried away with velocity/small port ideas and boast of ridiculous 318 power and 3.23 gears and 11's in the 1/4...but does anyone believe those claims from these people?
Have we seen any proof or even head work pics? Flow sheet ,time slip...anything? Nope!
So dont fall for arguing hypotheticals with bozos who are dancing in fantasy land. You want a port with enough cs, aka big enough for the airflow passing or it will be LESS than optimal, not more.
Click to expand...
Velocity is obviously important, but a lot of people are scared so much by it for some reason they throw away power by being ultra conservative with parts selection, I blame ford tunnel port 302 and boss to some extent and guys putting untuned or poorly tuned 750 on their **** combo turd engines like a 305 with just an oversized cam and untuned 750 holley and blame the carb cause it runs like ****.
 
273 said:
I find this guy Eric Weingartner of WeingartnerRacing videos on cylinder heads informative here's two of his latest

Is More Flow Better


Is The Smallest Intake Port That Flows The Most The Best


Mopar heads








Trick Flow SBM 190cc cnc Ported Head Review With Real Flow Numbers
Corrections, Updates And Small Block MOPAR Head Review
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Love Eric, spoke with him about a month ago. We've supported each other at the EMC for years. Eric rubs shoulders with some heavy hitters such as the Street Outlaws and is no stranger to making power. He is VERY experienced and well versed with everything SBC/BBC. While I don't agree with all of his ideology when it comes to making power or porting--You will do well to listen to him as he is one of the most honest and hard working dude I've known. J.Rob
 
Air Flow

Shop air compressors create high pressure air carrying moisture with it.

Plumbing the air compressor high air pressure exit into a larger 2" vertical drop pipe slows the air down and the suspended moisture turns back into a liquid and drops out the bottom cleaning the up the air for use.

Maintaining port speed and size keeps the atomized fuel in suspension.
 
RAMM said:
Love Eric, spoke with him about a month ago. We've supported each other at the EMC for years. Eric rubs shoulders with some heavy hitters such as the Street Outlaws and is no stranger to making power. He is VERY experienced and well versed with everything SBC/BBC. While I don't agree with all of his ideology when it comes to making power or porting--
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Everyone gonna have from slightly to wildly different philosophy, as long as produces results.
RAMM said:
You will do well to listen to him as he is one of the most honest and hard working dude I've known. J.Rob
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Good to hear, I've been watching him for a while, that's the impression I get.
 
RustyRatRod said:
What kinda flo is best? I like Linoleum. It's easy to keep clean.
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Flo or Flow?

Flo.jpg
 
I’m glad you asked those questions and I’m surprised for someone that always has a claim on how to make power, not to know some of those answers to the questions you asked.

Beyond just booting parts on and in the engine to make power, and the basic combination of parts which work well together, knowledge of the head becomes rudimentary first stop knowledge on what parts you are selecting.

Otherwise, you’re just blindly assuming and suggesting parts that you think will do the job. You think you’re standing on 3 base but in reality, you’re just making it to first. The more you learn the bigger the picture becomes and the more complex the engine becomes. It’s no longer a simple machine as you once thought it was.
 
rumblefish360 said:
I’m glad you asked those questions and I’m surprised for someone that always has a claim on how to make power, not to know some of those answers to the questions you asked.

Beyond just booting parts on and in the engine to make power, and the basic combination of parts which work well together, knowledge of the head becomes rudimentary first stop knowledge on what parts you are selecting.

Otherwise, you’re just blindly assuming and suggesting parts that you think will do the job. You think you’re standing on 3 base but in reality, you’re just making it to first. The more you learn the bigger the picture becomes and the more complex the engine becomes. It’s no longer a simple machine as you once thought it was.
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Guess your talking to me, never said I knew everything, I don’t pretend to have done more than I have, no one knows everything, and the more you know you find the less overall you know.

I only recommend at the level I feel comfortable, generally I try to provide information instead so the OP can make up their own mind since it mostly comes down to personal preference.


Most arguments I seem to get into is most people seem to think at least act like Torque and HP are two different kinds of power. And over exaggerate smaller engines deficiencies which there are but not to the level most make out or something related to these I don't need to be an engineer to know these basic truths.
 
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273 said:
Guess your talking to me, never said I knew everything, I don’t pretend to have done more than I have, no one knows everything, and the more you know you find the less overall you know.

I only recommend at the level I feel comfortable, generally I try to provide information instead so the OP can make up their own mind since it mostly comes down to personal preference.


Most arguments I seem to get into is most people seem to think at least act like Torque and HP are two different kinds of power. And over exaggerate smaller engines deficiencies which there are but not to the level most make out or something related to these I don't need to be an engineer to know these basic truths.
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235/273----.860 hp/cu in
230/318----.723 hp/cu in
275/340----.808 hp/cu in

Oh ya I know. The 340 was under rated, may be the HP 273 was over rated, HP was rated different, torque is king. Lots of excuses but these are as the factory rated them.
 
toolmanmike said:
235/273----.860 hp/cu in
230/318----.723 hp/cu in
275/340----.808 hp/cu in

Oh ya I know. The 340 was under rated, may be the HP 273 was over rated,
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340 & 273 came with similar head flow to cid ratio allowing both to breath, 318/360 both under headed especially 318.

toolmanmike said:
torque is king.
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Rpm is Queen and HP is their baby :)
 
273 said:
340 & 273 came with similar head flow to cid ratio allowing both to breath, 318/360 both under headed especially 318.


Rpm is Queen and HP is their baby :)
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Torque is produced and Horsepower is a calculation.
 
toolmanmike said:
Torque is produced and Horsepower is a calculation
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The pressure applied across the piston during the combustion which transfers force to the crank to be multiplied by stroke during one power stroke is Torque, HP is the sum of all those power strokes over time rpm. If your engine makes 400 lbs-ft at 3500 rpm it's making 400 lbs-ft per ever two revolution so 50% of 3500 = 1750 x 400 which is baked in the torque x rpm / 5252 = hp. If my engine makes 200 lbs-ft every two revolution, I'll have to spin 4 revolution for every two of yours in the same amount of time so twice the rpm to make same hp cause I'm basically making 400 lbs-ft in 4 revolution instead of two.
 
fishmens67 said:
68 Cadillac 472 ci 525lbs ft torque 375 hp.
torque doesn't always equate to horsepower
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Most leave out importance of rpm has on power, most automatically think high rpm when rpm and hp is mention, rpm is from idle until she won't go any higher and the engines hp curve is the same.
 
273 said:
Guess your talking to me, never said I knew everything, I don’t pretend to have done more than I have, no one knows everything, and the more you know you find the less overall you know.

I only recommend at the level I feel comfortable, generally I try to provide information instead so the OP can make up their own mind since it mostly comes down to personal preference.


Most arguments I seem to get into is most people seem to think at least act like Torque and HP are two different kinds of power. And over exaggerate smaller engines deficiencies which there are but not to the level most make out or something related to these I don't need to be an engineer to know these basic truths.
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Talking to you?
My apologies, the answer is no, but to everyone generally actually.
The question is a good one.

I also think your right, “
and the more you know you find the less overall you know.”
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As my parents used to say, “The older I get the stupider I become.”
With engines, I’d imagine that if one focused on one engine on one goal, there would be a finite amount of knowledge to learn.
What hasn’t been discovered is discounted.
 
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