THIS COULD BE A GAME CHANGER FOR THE NATURALLY ASPIRATED...

[97DFG]

-So, most everyone knows that the piston, on a naturally aspirated engine, creates a vacuum inside the cylinder on the intake stroke. Vacuum pressure is what draws the air in during those few milliseconds.

--So if you take two identical vacuums, but give one a small hose and the other a big hose, which one has more vacuum pressure? ...the one with the small hose...

-Having thought about that, then why do we put the biggest Intake, TB and intake manifold on our naturally aspirated engines?!? When this simple thought leads us, or maybe just me, to believe that we'll get more air into the engine with the smaller components! Obviously we see a better throttle response with a bigger TB, but at open throttle we would hypothetically make more power.

SMALL intake + SMALL tb = MORE Vacuum = MORE AIR = MORE HP
LARGE intake + LARGE tb = LESS Vacuum = LESS AIR = LESS HP

Then i think about what we see online for performance products as far as prices. Bigger diameter Intakes or TB's cost more and advertise HP GAINS. So are they really just lying to sell us more expensive products that will actually hurt our performance; when the cheaper and smaller intake items will help us Naturally Aspirated enthusiasts out...

Obviously these bigger intakes help the boosted community, but do we in the N/A community hurt ourselves for believing the same thing without thinking about it, I THINK SO..
*****PLEASE COMMENT WITH YOUR THOUGHTS!*****

 

[g36 monkey]

GO put on a throttle body, then put your car on a dyno. See if you gained or lost.

 

[Ferocious]

I don't think that's a game changer.

 

[97DFG]

Well maybe i outspoke myself, No doubt a bigger TB would create more power; But what I'm getting at is, would i see a greater power gain from a 4" JLT over a smaller SR Performance intake...on my mostly stock NPI GT...?

 

[Burninriverdiver]

So if I constricted the intake tube through a straw I would gain more hp? I don't see the logic. Bigger isn't always better, nor is smaller. I believe you will get the most out of a well researched and properly tuned setup..... I've spent money on parts that didn't necessarily help my hp, however I don't think constructing the air intake is the answer

 

[Burninriverdiver]

Well maybe i outspoke myself, No doubt a bigger TB would create more power; But what I'm getting at is, would i see a greater power gain from a 4" JLT over a smaller SR Performance intake...on my mostly stock NPI GT...?

Now that you've rephrased it, I don't think a bigger "cold air intake" will net you more hp. As a matter of fact, most cold air intakes will probably give you minimal gains regardless of diameter.

 

[97DFG]

So if I constricted the intake tube through a straw I would gain more hp? I don't see the logic. Bigger isn't always better, nor is smaller. I believe you will get the most out of a well researched and properly tuned setup..... I've spent money on parts that didn't necessarily help my hp, however I don't think constructing the air intake is the answer

I'm not saying go put a straw as your intake; but rather, on a N/A motor, a huge 4" diameter intake (JLT) will probably not give any more power than a 3" intake (SR). $260 VS $80
I guess i spoke way too broad for being the only one knowing exactly what application i was thinking about...

 

[RichV]

That's the debate, how to size all the components for the power level.

You need to size everything for maximum efficiency, ultimately your longblock determine what's possible. Then the intake and exhaust sizing will either help or hinder the power.

Look at it this way, a turbo/SC makes boost. The more boost, the more power right? Well that's not necessarily true because if your motor makes 400hp at 10psi and it's at the max of it's flow capability, you can't make 800hp at 20psi. It don't work that way. Just like a n/a scenario where decreasing the size of the intake makes more power.

 

[96blak54]

Keep in mind "cold air". Its the key word.

Youre correct about the vacuum higher with smaller tube and the correct tube size is important for inertia to take over. The cold air intakes are bigger to keep that incoming air off the hot surface of the intake tube. But Ford has to build fuel efficient, drivable torque, while still implimenting performance to compete at an exceptional value.

Is the cold air intake worth its weight? Debatable!

 

[Burninriverdiver]

I'm not saying go put a straw as your intake; but rather, on a N/A motor, a huge 4" diameter intake (JLT) will probably not give any more power than a 3" intake (SR). $260 VS $80
I guess i spoke way too broad for being the only one knowing exactly what application i was thinking about...

Sorry I jumped the gun without the specifics! You are probably right though on the cold air kits... You probably won't feel much if any increase in the hp between the two kits in my opinion. I don't know for sure, but you might be just as well off saving the $..... Welcome to the forums by the way!

 

[rz5.0]

Is also about volume.. You get more vacuum because of the restriction.. It's more complicated that just going small or big

Sent from my LGLS991 using Tapatalk

 

[Mustanger]

If I suck my drink through one of those little tiny stirring straws I get a LOT of vacuum but not much drink....I put a larger fat straw i n I get a LOT of drink with very little sucking or vacuum....I know this all sucks!

 

[white95]

Welcome to SN95forums

 

[Lanter]

Pressure isn't the key lever for power its flow. You have to match up what your engine desires to flow for peak efficiency with the piping that will give you that flow. More pressure does not equal more power unless that increased pressure also brings with it more flow.

 

[the5.ohh]

Upgrading a throttlebody is going to do nothing. You're putting a bigger hole for air to go into, then go right to the same restrictive intake manifold and heads. Therefore, useless.

 

[ttocs]

seems to me this would be more about the exhaust. Wouldn't a smaller exit of the gasses mean more pressure and mean more hp?! We need to get the air into the motor. Getting it out doesn't matter......

 

[DropTopPony]

Well maybe i outspoke myself, No doubt a bigger TB would create more power; But what I'm getting at is, would i see a greater power gain from a 4" JLT over a smaller SR Performance intake...on my mostly stock NPI GT...?

You won't really see a gain from either on your car. Bolt ons are almost a waste of money until you have ditched the stock intake and cams.

 

[97DFG]

Thanks for all of the comments, brings me back to reality and is much appreciated!

 

[Burninriverdiver]

Thanks for all of the comments, brings me back to reality and is much appreciated!

PI intake and cams are very affordable and easy to do! That with some decent bolt ons make a fun learning experience with the modular motor and a noticeable increase in throttle response... I enjoyed doing the cam and intake manifold swap (with the help and knowledge of these guys) and didn't spend too much money. It can be done for less than the jlt cold air intake and net you better gains (and knowledge)

 

[97DFG]

PI intake and cams are very affordable and easy to do! That with some decent bolt ons make a fun learning experience with the modular motor and a noticeable increase in throttle response... I enjoyed doing the cam and intake manifold swap (with the help and knowledge of these guys) and didn't spend too much money. It can be done for less than the jlt cold air intake and net you better gains (and knowledge)

I actually have two sets of PI Heads/Cams laying around, would just need the Intake Manifold. Would i have to tune the car after the swap..? This would also fix my leaking valve seal problem....