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Rockstar
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Discussion Starter #1
I have a couple of questions about the intake plenum spacer. I'm thinking about getting one from 3sx this fall, and I was wondering if it came with the gaskets, or if I had to get those seperate. I was also wondering if anyone that has one noticed any power gain?
 

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No surrender!
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What is a "plenum spacer" ? Will it let me change my back spark plugs without moving my plenum? That'd be sweet but how do you shut the hood?
 

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Rockstar
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Discussion Starter #4

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Rockstar
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Discussion Starter #5
...and no, you still have to take your plenum off to remove the spark plugs/wires on the rear cylinders. I haven't heard of any clearance issues with the hood, only with strut bars.
 

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AWD rules
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there has been numerous discussions about the plenum spacer. It probably won't do much at all. As discussed, the air is traveling too quick through your intake plenum for the extra heat to actually heat it up. Secondly, if the heat isn't being transferred to your intake manifold, it has to be transferred somewhere.
 

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Like a Bat outa hell!
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My understanding is that it keeps the UPPER plenum cooler to the touch.
That is a significant mass of aluminum to keep cool, and potentially reduces intake charge air.
You could argue that the air passes too fast for it to make MUCH of a difference.
But when you are modding your car, you are looking for every little trick for that extra elusive 1 hp.
And this quite possible could give you a small but not significant bump.
All the little things you do add up.
I have one, but not installed yet.
Knowing 3sx sells them makes me feel more comfortable about installing it on my car.

You may have to do some customizing on the back of the plenum to get everything to fit properly with this spacer.


Daniel
 

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The whole "air passes through it too fast" theory is bullshit, the air flowing through the plenum is travelling about the same speed as the air passing through the intercooler, and look how much an intercooler can alter air temps. Its all about surface area , which an intercooler has a LOT of, while the upper intake manifold doesnt. The temperature differential between ambient air and the intake air also plays a significant role, but I dont think that needs any explaining.

I agree that this mod wont produce any noticeable gains in terms of added power, but I have a plenum spacer (purchased from EK2 awhile back) and it does definitely keep the intake manifold much cooler than in stock configuration.
 

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SOHC you in the FACE
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i have some of these devices but I actually only use them because lifting the plenum allows me to flip a stock chrysler intake manifold

or with my custom intake I needed to lift the intake manifold in order to make room for the fuel rails.
Mine are about an 1" thick though.

I dont think they are the most effective devices but sometimes they can be useful.

My chrysler one is garolite and with the crappy chrysler design I still get lots of heat in the intake manifold.

My custom montero pattern sohc is a nylon spacer and the intake manifold actually stays really cool. I think a lot of that is the manifold design. The intake manifolds like the chrysler or the stock mitsu that hang over the rear head trap heat and that heat gets into the intake manifold.
 

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AWD rules
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well, until i see proof that they actually do something worth my 70 bucks, then my money will be spent elsewhere.

Besides, you can't compare an intercooler to an intake plenum.

Listening to all this crap about the plenum spacer is reminding me of listening to all the honda boys brag about how they pulled out a seat belt and saved 5 lbs.
 

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Like a Bat outa hell!
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Sorry about bringing this from the grave but:
My understanding is that it keeps the UPPER plenum cooler to the touch.
That is a significant mass of aluminum to keep cool, and potentially reduces intake charge air.
You could argue that the air passes too fast for it to make MUCH of a difference.
But when you are modding your car, you are looking for every little trick for that extra elusive 1 hp.
And this quite possible could give you a small but not significant bump.
All the little things you do add up.
I have one, but not installed yet.
Knowing 3sx sells them makes me feel more comfortable about installing it on my car.

You may have to do some customizing on the back of the plenum to get everything to fit properly with this spacer.


Daniel
The whole "air passes through it too fast" theory is bullshit, the air flowing through the plenum is travelling about the same speed as the air passing through the intercooler, and look how much an intercooler can alter air temps. Its all about surface area , which an intercooler has a LOT of, while the upper intake manifold doesnt. The temperature differential between ambient air and the intake air also plays a significant role, but I dont think that needs any explaining.

I agree that this mod wont produce any noticeable gains in terms of added power, but I have a plenum spacer (purchased from EK2 awhile back) and it does definitely keep the intake manifold much cooler than in stock configuration.
Knowing 3sx sells them makes me feel more comfortable about installing it on my car.

You may have to do some customizing on the back of the plenum to get everything to fit properly with this spacer.


Daniel
Then you should buy one of these !
http://www.3si.org/forum/showthread.php?t=379690&highlight=plenum+spacer+3sx
sportsb4life7: If you would have read the post above yours,
maybe you could comprehend the age old well known fact that ANYTHING
that reduces underhood temperatures is a plus for overall performance.
And that is exactly what this spacer is designed to do. And it does.
And I don't believe that anyone on this forum who has any integrity is going
to argue that a part that decreases underhood temperatures is useless.

The throttle body spacer with the "Helix" design you're referring to has
not shown to do anything but actually decrease performance.
However, smooth throttle body spacers HAVE been shown to increase performance on SOME vehicles.
And the "Helix" design has been shown to produce a whistling sound at certain RPM's.

So, please, before you try to embarrass someone with a post like that,
do a little research so you don't embarrass yourself.

Not trying to start a flame war, but trying to set the record straight.


Daniel
 

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I don't know about your cars but with mine WITH a spacer.....

I can drive my car all day without hitting boost and the plenum doesn't get hot .

However if I give it boost , hard boost for a short time, the plenum DOES get hot.

So it's not too hard to figure that the heat comes from the intake charge rather than getting conducted from the heads and lower plenum.
Not only that but a spacer will disrupt flow unless it's matched perfectly at both sides.

It's a performance looser.
 

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Considering 3SX sells them and has access to an in house dyno, mabe Steve can have one installed on a stock car and note the dyno gains..This is the only way to get some real results.
 

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lurking again
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Knowing 3sx sells them makes me feel more comfortable about installing it on my car.
HAHAHAHAHAHAHAHAHAHAHAHAHA... maybe i should go order some key chains too :D

anyway... back on topic... i also have one of the ek2 plenum spacers... i think i paid $35 or $45 for it... i used it for a little while and it does decrease the temperature of the upper plenum... and i have seen a *slight* decrease in actual intake temps as measured by my autometer IAT sensors... but it is not enough to actually affect performance and the difference in temperature as seen by gauge was not enough to be considered outside of the margin of error (read: affected by difference in ambient for example).
 

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I got myself one of these spacers mainly because i didn't want to hack up the rear of my intake manifold in order for it to fit back on along with my adapter plate setup...
 

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Considering 3SX sells them and has access to an in house dyno, mabe Steve can have one installed on a stock car and note the dyno gains..This is the only way to get some real results.
Well lets see if that happens. Shouldn't be hard, doesn't even have to be a stock car.

Every other person at 3sx has a 3s of one sort or another so should be hard to test their own products.
 

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User
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snip...
sportsb4life7: If you would have read the post above yours,
maybe you could comprehend the age old well known fact that ANYTHING
that reduces underhood temperatures is a plus for overall performance.
And that is exactly what this spacer is designed to do. And it does.
And I don't believe that anyone on this forum who has any integrity is going
to argue that a part that decreases underhood temperatures is useless.
snip...

So, please, before you try to embarrass someone with a post like that,
do a little research so you don't embarrass yourself.

Not trying to start a flame war, but trying to set the record straight.


Daniel
first law of thermodynamics: energy is neither created nor destroyed.

If your plenum is cooler, it's hotter somewhere else under your hood. Thus, you are not lowering under hood temperatures.

While you can say that the air passing through the plenum is less effected by the heat, it would be more advantageous to just get the plenum coated in something that would trap heat.

Plus you are changing the length of the runners. This has other affects.

Also not trying to start a flame war, but advice given should also be taken.
 

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Evolved Member
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first law of thermodynamics: energy is neither created nor destroyed.

If your plenum is cooler, it's hotter somewhere else under your hood. Thus, you are not lowering under hood temperatures.
Agreed. The rest of the engine will just contain the extra heat that the plenum would have eventually gotten when the engine heats up. Simple understanding in the first section of this: http://www.physchem.co.za/Heat/Heat.htm
 
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