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Do manifold and plenum spacer actually do anything to justify
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Do manifold and plenum spacer actually do anything to justify the cost, either on their own or along with other mods?
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Maybe.
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>>14722205
improves top end
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>>14722452

nah, improves low end torque but gains are dependent on cams
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>>14722205
>all this work on a 3800
Why?
>>14722516
Whats the actual reason behind this? Allows more air in the intake or more space in the intake runners?
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>>14722516
"No"
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>>14722524

resonance and pressure waves inside the manifold
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>>14722525

Yes, they increase volume, lowering the frequency of pressure waves (because of the increased volume) and increases torque at low rpms
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>>14722637
Do they fuck. They're about airflow not waves.
They stop it choking at the top in exchange for a loss of throttle response.
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>>14722656

stop and think for a second retard, how is increasing the volume of the plenum going to increase airflow without any change to the throttle body or filter? You think having an extra mile of inlet manifold would somehow increase air intake?

https://en.wikipedia.org/wiki/Inlet_manifold#Volumetric_efficiency
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>>14722694
If the throttle body was a restriction it would
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>>14722694
come back when you've actually worked on a car and have seen the effect of the mods you're pontificating about
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>>14722713
http://www.enginebasics.com/Advanced%20Engine%20Tuning/Intake%20Runner%20Length.html

You want to rethink what you said? An intake spacer would increase the distance the pressure wave has to cover. This would result in better flow at lower rpm.

You can say what you want about "your mods" but unless you show proof of said mods and pre and post modification dyno sheets it is much safer for me to follow well understood theory.

Furthermore, what you are saying just doesn't make any intuitive sense.
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>>14722713

come back when you can wrap your head around basic concepts like volume and air density
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>>14722764
plenum spacers don't change intake runner length
increasing the distance the wave has to cover weakens it
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>>14722784

plenum spacers are not made to arbitrarily increase the length the wave travels, but to tune the oscillations to a certain RPM range, there will be no significant weakening of the force in the wave over the kind of distance we are talking about
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>>14722784
Well making a constant pressure differential assumption (completely reasonable), it would change your dP/dx. Which discussing bulk fluid flow, this would effect your mean fluid velocity.

However, we are discussing a pressure wave that has a slight turbocharging effect on the fluid that is travelling into the intake valve. This pressure wave *always* travels at the speed of sound. Thus the only thing that will change is the time of flight. Thus given a fixed time of flight (which increases with runner length) will result in a turbocharging effect at lower rpm.
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It's going to depend on a lot of things. Firstly, the runner length you want is dependent on the plenum volume, and vice versa. You might want a different combination than stock, but there's plenty that can be done that's probably a better decision. You have to make sure your car will adjust to the change or have it re-tuned. So if you have a super high budget build, maybe, but mostly you probably shouldn't bother.

tldr, if you trust the person selling the kit has done proper simulation work and testing, go for it. If you're looking to nigger rig a spacer, than fuck no.
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>>14722205

I have a manifold spacer but it's for heat purposes not to add volume or anything like that.
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>>14722205
>>14722205

What's that in? Just add a blower. 3800s aren't known for torque so anything can help
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