New Product Alert! Interest in insulating intake manifold spacer?

[Def]

I'm currently talking to a company that makes insulating intake manifold spacers. Basically these are just 1/8-1/4" thick spacers of a plastic material that does not conduct heat very well. This serves to dramatically reduce the temperature of the intake manifold, which consequently reduces the temperature of the intake air going through it. Since our intake manifolds offer such a large surface area, and get pretty hot even though they're of thermoplastic construction, I think we stand to gain a fair bit of power from this modification.

Here is a sample dyno of a VW Passat 1.8T, the only addition is the manifold spacer:



Their Honda applications retail for $60, and I'm assuming that if they made spacers for our applications that the price would be roughly the same.


This isn't the end all be all of power mods, but I'm of the opinion that every little bit helps, and the price is certainly attractive. If there is sufficient interest then I'm sure the company can be convinced to make spacers for our inline 6 engines, although I'm guessing it would be a least a few months before they could go into production.

Just as an estimate, I would see the installation of this taking about 1.5-3 hrs depending on your skill and tool collection. It's not hard, but the rearmost bolt on the manifold is a bit tight to get to.

[E36DJ]

I'd be interested!

[Balthazarr]

Interesting.

[Kenzo]

It makes sence if we had heat conductive aluminiun manafolds...not sure about our thermoplastic design?

Removing the TB coolant lines and maybe the thermo blanket/shield like the European Car Project M3 might make more sence?

TIA

[Jeremy Lucas]

The heat in the intake is from the intake being entirely over the engine so it's radiated heat not conducted heat. The spacer won't do you any good, certainly not the results your looking for.

[ImageDynamicsM3]

this will also add to the runner length by whatever the depth of the spacer is. I have seen good improvements on N/A honda's. Same with throttle body spacers.

[jeebus]

here's a detailed thread about these that I participated in over the last few months. I was considering one for my GSR.

http://www.honda-tech.com/zerothread?id=624233

[bimmer95]

News flash: our intakes are already plastic. Insulating a plastic intake with a plastic spacer is only going to improve your power to weight ratio by lightening your wallet :

[Def]

Originally posted by bimmer95
News flash: our intakes are already plastic. Insulating a plastic intake with a plastic spacer is only going to improve your power to weight ratio by lightening your wallet :

News flash: not all plastics have the same thermal conductivity. These spacers use some teflon-based plastic, which is an excellent insulator. Our thermoplastic manifolds, while offering more resistance than a cast aluminum one, still get VERY hot after driving around. I highly doubt all that heat is coming from radiation and convection given the geometry of everything beneath the manifold. Although you can go on being smug in your apparent "discovery" that plastic is plastic is plastic. :


There is alot of radiant heat energy intercepted by the manifold from the engine block, so some reflective and insulating material placed below it probably would see some benefits as well.

The TB coolant bypass is a no-brainer mod for cars in warmer climates as well. I would planning on doing both these(spacer and bypass) at the same time.

[Def]

Originally posted by Kenzo
It makes sence if we had heat conductive aluminiun manafolds...not sure about our thermoplastic design?

Removing the TB coolant lines and maybe the thermo blanket/shield like the European Car Project M3 might make more sence?

TIA

My thought is that our intake manifolds definitely get quite hot after even moderate driving. Therefore they are receiving heat energy from the engine.

Why I think conduction is a "big part"

1. The airflow will be largely stagnant or very low velocity in this region - leading to a low coefficient of convection.

2. There are more than a few objects underneath the manifold to help shield the intake from a large portion of the thermal radiation. At the temperatures the intake manifold is reaching, radiation would be a VERY minor contributor given how it mostly plays a role in much larger temperature differentials.

3. The intake manifold contacts the head over a relatively large surface area, with nothing inbetween the head or manifold to hinder heat transfer. This junction has very low thermal contact resistance when compared to another car that has maybe a paper gasket. Heat flux from the head to the manifold is virtually uninhibited.

4. While the manifold does have a low thermal conductivity compared to aluminum, the temperature differential and heat flux it is exposed to is large enough to slowly bring it up to a temperature almost equal to that of the mounting surface of the head. Thermal conductivity does have a role in the heat flux coming in, but it is apparently large enough given the small heat capacity of the thermoplastic material(i.e. less energy needed to raise its temperature compared to aluminum) to be a major contributor to its total incoming heat flux.

Adding a VERY low thermal conductivity spacer would increase this thermal contact resistance to such a level as to hopefully make the conductive heat flux low enough to keep the manifold at a reasonable temperature.



Obviously there is a heat problem in our manifold given how hot it stays even with steady state cruising. This might not be the only answer, but it is definitely not that expensive in the grand scheme of things, and it does show promise of largely reducing the heat flow coming into the manifold.

...and btw, I know the manifold is made of plastic.

[bimmer95]

:
This makes nearly as much sense as the heat shield around a Dinan style intake idea.

[Def]

A heat shield around a Dinan intake *IS* a good idea. Feel the tube sometime. If it's hot, it is transferring heat to the air flowing through it. Surface area and airflow velocity as well as temperature differential play the largest role in the total heat transfer.


It seems like you completely don't understand the first thing of what I'm saying. So why don't you respond back with MEANINGFUL CONJECTURE instead of your cutesy BS flag and some inane comment that only proves my point.

[Ali]

I have a heatshield around my dinan intake and its no longer hot after a really long or hard drive, especially on a hot day. Also keeps the cf in better condition. This product makes sense, the intake manifold does get pretty hot when run hard.

[Kenzo]

Will it be an easy install...remove covers, a few bolt, slip in place and bolt back up?

Don't discount heating due to underhood temps. My metal ECIS extension tube isolated by the heat shield between the filter and HFM gets damn hot during stop & go driving.

What is the general "rule of thumb" for intake air temp vs hp?

[m42technic]

Originally posted by ImageDynamicsM3
this will also add to the runner length by whatever the depth of the spacer is. I have seen good improvements on N/A honda's. Same with throttle body spacers.

For low end, yes. The top end power will suffer though.

Why not remove the intake heater if you want to lower intake manifold temperatures? Keep in mind it wouldnt be such a great idea if you live in a cold climate...

[m42technic]

Originally posted by Kenzo
What is the general "rule of thumb" for intake air temp vs hp?

Generally, about 10ºF = 1% HP difference.

[Def]

What is the general "rule of thumb" for intake air temp vs hp?

The general rule of thumb I've heard thrown around is about 11*F increase in intake air temperature decreases power by about 1%. I don't think it'd be all that hard to reduce intake air temp 10-20*F if you bypassed the throttle body coolant lines and put this spacer in. Maybe some reflective HVAC tape on the underside of the manifold if you really think the radiant heat of the engine is making a big difference.


As for reducing top end power, the percentage increase in runner length by adding a 1/8-1/4" spacer is negligible at best. I suspect power close to redline will be almost identical given that the air is spending less time in the manifold to absorb heat, and this increase in runner length would make no difference at all.

[BMW M Power]

can someone explain what this intake heater is???? and how to remove it???

i have a 99....if that matters.

tia

[Def]

There are two coolant lines going into your throttle body. This serves to heat it up and prevents the throttle plate from icing in position on very cold and humid days.

Just remove the lines and put a straight connector between them to bypass this.

[SI///M3]

If it is cheap enough and the install is simple enough given the gains I'd be up for it.

[BMW M Power]

would these be the coolant lines??? so i just connect the lines together?
should i cover up the open connections on the tb???


and i guess the big question is......what are the temperature savings going to be???? and what does that translate into performance??

thanks,
Brent

[Def]

Yes, those are the lines.

The gains won't be noticeable. Enough mole hills and you've got yourself a mountain though.

[BMW M Power]

true about the mole hills.

do you even think that this would reduce intake temps by even a measureable ammount??

[BMW M Power]

and....do you close the open holes in the tb????

[Def]

This "mod" is pretty self-explanatory.

Really, this thread isn't here to talk about bypassing the coolant going through the throttle body, but more about the possible interesting in an insulating intake manifold spacer.