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Discussion Starter #1
I have asked this before but cannot find an answer so please pardon my post.

How does adding a spacer add MPG and/or HP? It is just a spacer afterall, or is the more to this mod?

Also can someone tell me how much this cost? And knowing what they know now would they install this mod again?

Thanks!
 

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the IMS has been independently dyno'd by 3 people and has shown drastic torque improvements, especially at the lower end, one dyno i saw showed a 30 ft-lb increase in power at 3k rpm. it works by allowing a larger volume of air available to the engine to be put in during intake valve openings. there is no trickery behind it. in "old school" talk this is the modern day equivalent of throwing a bigger intake and carb on the old small block v8's. you when increase the flow of air (especially in combo with a cold air intake) the engine does make more power. the IMS retails for $259.99 on WRP's website but i think there was a member here selling his in the for sale threads not too long ago. as for your last question, i can't answer that since i don't have one
 

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Discussion Starter #6
So maybe I'm being a little stupid here...how does adding a spacer increase the volume of air?

In a naturally aspirated engine it would seem to me that adding a spacer would not increase the volume of air. Upstream and downstream of the spacer you would still be limited by the diameter of the induction pipe/manifold. If the spacer somehow cooled the air then I could understand as cold air is more dense than hot.

I'd really like to understand this. Thanks.
 

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So maybe I'm being a little stupid here...how does adding a spacer increase the volume of air?

In a naturally aspirated engine it would seem to me that adding a spacer would not increase the volume of air. Upstream and downstream of the spacer you would still be limited by the diameter of the induction pipe/manifold. If the spacer somehow cooled the air then I could understand as cold air is more dense than hot.

I'd really like to understand this. Thanks.
Just think of adding a spacer to a can or bottle. You increase the capacity of the container to allow more air or whatever to fit inside the space.
 

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yea like chuck said, it doesn't add to either plenum individually but by spacing them out it adds to them as a whole
 

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So maybe I'm being a little stupid here...how does adding a spacer increase the volume of air?

In a naturally aspirated engine it would seem to me that adding a spacer would not increase the volume of air. Upstream and downstream of the spacer you would still be limited by the diameter of the induction pipe/manifold. If the spacer somehow cooled the air then I could understand as cold air is more dense than hot.

I'd really like to understand this. Thanks.
As others have noted, the IMS increases the volume of air entering the engine by increasing the volume of the intake plenum. The more you have to suck, the more goes in. Simple.

I wonder if there is a limit to this. Suppose we double the IMS. Would we get 60 lb-ft extra in torque?
 

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I wonder if there is a limit to this. Suppose we double the IMS. Would we get 60 lb-ft extra in torque?
the limit would probably be (based on engine fundamentals 101) valve size and/or fuel injector psi. upgrade both and a larger plenum would benefit. this would also need to be followed by a higher flowing exhaust to equal the extra intake side volume

He has, it is in the IMS thread.
what he said:goodjob: it's also on his website
 

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Just Ask For A Discount Without Gaskets And Go Get Your Own Gaskets. A Few People Have Had Problems (ME INCLUDED), And So Far Not Much Help From The Manufacturer With No Word Of A Fix. IT DOES MAKE POWER THOUGH.
 

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Discussion Starter #14
Just think of adding a spacer to a can or bottle. You increase the capacity of the container to allow more air or whatever to fit inside the space.

If you added a spacer you would increase the capacity but fluid can only flow in (or out) at a rate based on the pressure and/or the smallest opening which may act as a metered orifice.

In other words if you had a water bottle and added a spacer, yes the volume capacity would increase but you would not be able to remove or add water any faster because of the restriction at the neck of the bottle.

Back to our trucks...maybe the spacer allows the temperature of the air to cool. And the cooler air would be more dense so more oxygen would be in the same volume of air.

But then again maybe I'm the dense one. :)
 

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If Ya'll Really Want To Know What Affects Youre Dealing With Go Research Intake Runner Lengths. You Get Very Different Hp And Tq Outputs And And Different Rpms Depending Upon Runner Length, Volume, Open Or Individual Plenum Etc. The Varied Spectrum Could Be Looked A Simply Without Taking Into Other Considerations As, Imagine The Different Behavior Of The Same Engine Comfiguration With Only Changing The Intake, 1 Has A Big Open Plenum Box Right Between The Heads That All Cylinders Draw From, The Other Has Long Individual Tubes Feeding Each Cylinder. The Same Applies To Headers, You Get A Different Response From An Engine With Short Tubes That All Dump Into A Common Log Right After The Exhaust Ports, Vs Long Primary Tubes That Then Dump Into A Collector Further Down The Exhaust Path. And This Doesnt Take Into Tuning Each Individual Setup For Optimum Output. You Also Need To Know What You Intended Use Is. A Truck The Needs To Tow Is Going To Need A Different Setup Than One That Wants To Have A Street Race Setup Or Variences In Between
 

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the difference in power is a result of changing the runner lengths and getting better cylinder fill from this part - having the longer runner allows more velocity behind the air to push the air into the cylinders :)

side note, we have a resolution on the gaskets
 

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Discussion Starter #18
Thanks Wperdigon.

Brutal why did you capitalize each word? Makes a good post a pain to read, imho.
 
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