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Discussion Starter · #1 ·
Searched the forum many times and though I have seen many mentions of them being added, outside of the temperature reduction to the intake manifold, not much discussion.

since I live in a hot climate anything that can assist with hot air is worth a shot so I ordered a set from PAW and they just arrived.

two questions for those of you in the know:

1) PAW mentions the need to apply copper gasket sealant. Really? Never heard this before (I’m fine with it) but curious as to everyone’s thoughts why?

2) I understand the concept on keeping the intake manifold cooler but why the throttle body, as it is attached to the bottom of the intake manifold… wouldn’t the intake manifold phenolic spacer solve the heat issue for both?

or am I missing some obvious (not to me) logic here?
 

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Discussion Starter · #2 ·
Sorry a third question…
If the intake manifold was acting in some ways as a heat soak for the head and the point of the spacer is to insulate against that.. isn’t that akin to removing part of the heads ability to dissipate heat?
 

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Sorry a third question…
If the intake manifold was acting in some ways as a heat soak for the head and the point of the spacer is to insulate against that.. isn’t that akin to removing part of the heads ability to dissipate heat?
I have never seen any indication that the intake is used to remove heat from the head, and there is no good that results from heating it.
 

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Discussion Starter · #4 ·
I get the intake being cooler = good-er.

however engines are a system and I always wonder what the trade offs are when making alterations to an original design. Logic tells me that by removing the conductivity from the head to the intake I am removing mass / surface area from the heads ability to cool.
Probably doesn’t matter but a thought none the less..
 

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Any additional cooling for the head is trivial compared to the need to keep anything dealing with fuel cool. Many cars have phenolic spacers to keep from heating fuel - even more so with carbs as a float near a header can make a huge difference in performance. The copper containing sealants are just a high heat form of the usual, be they Permatex or other manufacturer's.

If the claims here are correct, it is worth doing. I haven't bothered for the street.

 

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Is the LNF intake manifold metal? I'm under the impression that the LE5 is plastic (am at work, can't look now). Being plastic it would already not absorb nearly as much heat as a cast aluminium manifold... would it?
 

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Good question - I haven't had one off so I don't know (think they are alloy, though) , but someone will answer soon. I agree that a plastic manifold isn't going to conduct heat like a metal one and probably wouldn't need insulation.
 

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Discussion Starter · #8 ·
Is the LNF intake manifold metal? I'm under the impression that the LE5 is plastic (am at work, can't look now). Being plastic it would already not absorb nearly as much heat as a cast aluminium manifold... would it?
At least on mine (GXP / LNF) when i last had it off for the great stuck washer removal incident, it appeared to be aluminum or a version of that metal and very similar to the head it was mated to.
 

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Discussion Starter · #9 ·
Is the LNF intake manifold metal? I'm under the impression that the LE5 is plastic (am at work, can't look now). Being plastic it would already not absorb nearly as much heat as a cast aluminium manifold... would it?
I was searching the forum for previous posts on phenolic spacers and came across an old thread where someone mentioned the NAs having plastic intake manifolds. Love to see a pic of one of anyone has one..
 

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Discussion Starter · #10 ·
Any additional cooling for the head is trivial compared to the need to keep anything dealing with fuel cool. Many cars have phenolic spacers to keep from heating fuel - even more so with carbs as a float near a header can make a huge difference in performance. The copper containing sealants are just a high heat form of the usual, be they Permatex or other manufacturer's.

If the claims here are correct, it is worth doing. I haven't bothered for the street.

Also FWIW, my goal is less heat. I have doubts about additional HP but as the old man once said “how could it hoit?”
 

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It makes sense that the turbo manifold be cast alloy as it has to be made out of a resistant material able to withstand the high boost. Whereas the LE5, not being boosted, can benefit of the lighter weight and less heat soak properties of polymers.
 

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It makes sense that the turbo manifold be cast alloy as it has to be made out of a resistant material able to withstand the high boost. Whereas the LE5, not being boosted, can benefit of the lighter weight and less heat soak properties of polymers.
Not following your logic regarding "high boost" and the "heat soak" properties of polymers. I can assure you that there are plenty of polymers that can handle 23 or so psi of pressure and can withstand the temperatures that would be at the base of the intake manifold. I'm far from an expert on turbocharging but it's my understanding that a cooler air/fuel mixture creates greater explosion and thusly more power. In my mind an intake that conducts less heat from the heads would create a better condition for ignition.

Not intending to be argumentative, just wanted to sort this out in MY mind!
 

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Not following your logic regarding "high boost" and the "heat soak" properties of polymers. I can assure you that there are plenty of polymers that can handle 23 or so psi of pressure and can withstand the temperatures that would be at the base of the intake manifold. I'm far from an expert on turbocharging but it's my understanding that a cooler air/fuel mixture creates greater explosion and thusly more power. In my mind an intake that conducts less heat from the heads would create a better condition for ignition.

Not intending to be argumentative, just wanted to sort this out in MY mind!
I'm sorry, I might have not made my points clear.

1) I believe that at the time of its inception the LNF might have been specified with a cast alloy manifold due to it having been for some reason considered more resistant to a boosted environment.
2) I believe that the LE5, not having to work with boost, was specified with a plastic/composite/polymer intake manifold due to not having to withstand boost, which would allow a lighter, cheaper part that as an added bonus, would not transfer as much heat from the head to the intake air (ie. "less heat soak" -- sorry for my not perfect English!)

My wife's Golf is a factory boosted car and has a plastic intake manifold/air cleaner housing/PCV check valve. It's all 3 things into one and maybe more. I'm sure that if it was specified by the factory it means that it can take the boost OK (even though it had to be changed under warranty due to the check valve "body" having "unwelded" itself from the manifold body and started leaking boost. Seems it had a manufacturing defect on the plastic weld there).
 

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Discussion Starter · #14 ·
My second question nobody addressed and I am still curious..
Why the phenolic throttle body spacer?
Logic says that since it’s mounted to the underside of the air in take manifold, once you thermally decouple the air manifold, doesn’t that translate to the throttle body?
 

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My second question nobody addressed and I am still curious..
Why the phenolic throttle body spacer?
Logic says that since it’s mounted to the underside of the air in take manifold, once you thermally decouple the air manifold, doesn’t that translate to the throttle body?
I was thinking about this too when you asked and couldn't make sense of the why. Maybe it's a "we'll throw this one as an extra to give the kit the impression of a better value deal" thing?
 

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I was thinking about this too when you asked and couldn't make sense of the why. Maybe it's a "we'll throw this one as an extra to give the kit the impression of a better value deal" thing?
I'm going with this. "If one is good, buying two must be better, right?"

I agree that if you decouple the heat transmission, you shouldn't have to decouple it again! lol
 

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Discussion Starter · #17 ·
From the Werks site for the throttle body spacer (I didn’t realize you could buy them separately)

In our continuing improvement of the GM LNF/LDK/LHU engine platform is the WERKSracing LNF/LDK/LHU Throttle Body Spacer!!! The High Temp HDPE material lessens heat transfer between the aluminum throttle body and the aluminum intake manifold. Our testing has shown a 20 degree (F) reduction in thermal heat transfer between the 2 parts with the spacer installed.
 

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Throttle body spacers have been used for many many many moons. A stock intake manifold typically doesn't have any storage capacity so to speak. The purpose to the spacer it to provide a little bit of extra storage. Now I know it seems almost pointless because how much space can it really add. Believe it or not that small amount of air will help throttle response.

The intake manifold spacer is dual purpose. It reduces the amount of thermal bridge between the head and the intake manifold. The cooler the intake manifold the less heat gets gets absorbed into the air (cold absorbs heat). Because of the amount of sheer surface area inside of an intake manifold the amount of heat that gets transferred into the air is pretty high. The more fuel and the more O2 molecules you can get into a cylinder the more power the engine is going to produce. This gets an even higher bump in a boosted application because the charge air is going to be cooler that means the burn temps are going to be cooler and as a result you can advance the timing more which will give you a large bump in HP output. This would happe even more so if the intake temperatures are cooler then the charge air passing through the intake. Remember cold absorbs heat so the intake manifold would help reduce the charge air temperatures further then what the CAC was able to.

The second thing the intake spacer does is it increases the length of the intake runners. This is just like the TB spacer in it will increase the volume of the intake manifold. If the head and intake manifold are port matched the increased length in the intake runners will increase the velocity of the air moving through the intake. higher velocity = more air in the cylinders = more HP.
 

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Discussion Starter · #19 ·
Thanks KG.
All makes logical sense to me.

drove it a small amount yesterday on surface streets.
Can’t say I noticed anything, nor was I expecting to however it has been cool by LA standards lately and I didn’t run it hard.

honestly the car has always seemed to act up when I try to granny it. It seems to prefer and, is most happy with a medium to heavy foot :)

I have never had a motor that seemed to change its behavior so much based on weather..
that being the case I figured the spacers certainly couldn’t hurt and gave me an opportunity to replace the crank sensor (which I had gotten but never got around to when I was chasing the sputtering).
I believe I have the oil pressure and fuel pressure sensors left and everything else is brandy-New in that department…
 

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you may have to have your tune adjusted so it works better with the spacers. You could have a slight lean condition happening on acceleration and that would negate any benefits because the ECM is not dumping in more fuel for the increase in air. have to log the vehicle to see where the lambda values are at to see if that is happening at all.
 
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