I was wondering how an intake manifold spacer helps you make more power. I could only think of two ways:

-One, it would absorb heat???
This could help as it absorbs some of the heat going into the engine but I also
see it sucking in regualar engine bay heat.

-Two, it creates a longer path for hot air to travel and provide a better chance for it to cool off before entering the CC.
This sounds logical but why wouldn't we just extend the IC piping to take care
of this???

Please teatch me. Thanks, John.

Its basically just an thermal insulator between the intake mani and the head, it helps keep the intake cool, by preventing heat transfer from the head/engine.

how does it prevent heat transfer? Does it absorb it or something?

It insulates the intake manifold from the heat of the engine/head.Phenolic is a pressed together fabric material and resin.

It works, you want proof? I would be more than willing to show you how well it works anytime you wanted.

How would you be able to show me???

How would you be able to show me??? [/b][/quote]
Do a few pulls side by side with him. Touch your intake manifold, then touch his.

We have totally different setups. I think his FMIC would be more efficent than mine as I am on a larger turbo than him. It would be easier to cool down his intake charge than mine, especially since I am running lean and very untuned. I see your point though if we had similar modded cars.

Can a temp difference be spotted on a temp gun? Can you read the heat off the intake mani and get a noticable difference in reading the head or something?

I don't think the difference in your setups would matter in this case.Without the spacer, your intake manifold is almost always gonna be considerably hotter than the intake air.You don't need a temp gun to check it out, put your hand on your intake manifold after you've been driving, you'll probably get burned.With a spacer(from what I've heard) your intake manifold stays cool enough to touch.The difference should be huge regardless of your turbo or intercooler.I'll be putting one on my almost stock 2G(14b, stock IC and boost levels) when they get the materials, you can check it out.

The key way I know it is working is when I can touch my intake manifold and it be cooler than my intercooler piping. That is the spacer doing its job right there.

Shouldn't the ic piping be hotter than the intake mani though? The ic piping gets heated because of the hot air leaving the turbo. The longer the route for the air to travel, the longer the air has to cool off before entering the head. This leads me to believe that the intake mani would normally be cooler than the ic piping. Also, the intake mani is thicker so it would take more heat to penetrate the surface.

So you say the spacer insulates the intake mani. Don't the intake temps come from the ic piping, not the head? Or is it the head that heats the intake mani backwards?

Sorry, just trying to figure things out. I will probly go with one but want to know how the "big difference" comes in. Seems to me like long route ic piping would help then...

He was talking about the I/C piping post-intercooler. No shit the piping right off the turbo will be hot.

Your thoughts about air traveling further and being given more time to cool off are pointless. The air is contained in a metal pipe, which not only is getting constantly heated by the heat under the hood but by the air in the pipe itself. It is also traveling so fast that the few feet it travels is negilgent in it actually having time to cool off during its journey. Once air leaves the intercooler it will heat up again before it cools off. Like I said, engine heat will always keep the piping and manifold hot, nothing we have will ever be perfectly insulated against heat.

The head does in fact give the intake manifold the majority of its heat. Direct contact with the engine will do that to anything.

Trust us. With the phenolic spacer in place you can touch the intake manifold where as you can not without it.

your intake manifold and head are huge heat sinks for the engine to disipate heat threw. Now the air traveling threw your IC piping and intake manifold takes heat from the piping and manifold, there for being hotter then it needs to be, so if the manifold is colder, there will be less heat transfer. Which will provide a cooler more dense air charge which = more power.

~John

oops

didnt you just argue against a phenolic spacer being worthwhile?

"Your thoughts about air traveling further and being given more time to cool off are pointless. The air is contained in a metal pipe, which not only is getting constantly heated by the heat under the hood but by the air in the pipe itself. It is also traveling so fast that the few feet it travels is negilgent in it actually having time to cool off during its journey. "


so how does the heat of the metal intake manifold matter for the 12" the air travels through it at high speed? if the heat dissapation when in the I/C piping is negligable because of the time the air spends in it/the speed at which it's moving, wouldn't the heat absorption in the intake manifold be even more negligable since the air spends even less time in it as it's travelling like 1 foot through it at the same speed as the I/C piping?

who cares how hot a flame is when all you're doing is waving your hand through it at high speed? your hand isn't in it long enough to be heated and burned.

The air has a relatively low mass compared to the pipe and the manifold, so its easy for the manifold and pipe to transfer heat to the air, but not the air to the pipe and manifold.Matt D is right, I think you just missunderstood what he was trying to say.

I was talking about the piping after the intercooler. I am not that stupid. Heat wrap will help cool off the ic pipes.

I don't see how a small, 3/8" spacer is going ot make a work of difference but I will go with it. I think that an aquamist system would help much more though. BTW Matt, you can be the first one to touch my intake manifold ;) .

Oh, and for the record, I am not getting the spacer so I can touch my intake mani if I want. I think that is a stupid reason to get it. I am hoping it will help performance a little.

Being able to touch the manifold was just an example of how good the spacer works, not a reason for getting one.Phenolic spacers cool down the intake charge, water injection serves an entire different purpose.

Exactly - Water injection is NOT for cooling the intake air.

The phenolic spacer is made of a resin, it is similar to fiberglass but not quite the same. It is an EXCELLENT insulater even if only 3/8" thick, and does its job quite well.

Heat wrap is not an active cooling solution. It is an insulater much like the spacer - it prevents heat transfer. But once the pipe beneath the wrap is heated it will take just that much longer to cool off because it is insulated from the ambient air. If you are seeking to reduce underhood temps your best bet is to start insulating items that emit heat, such as the numerous exhaust components.