Fellas,

I got my Injen installed and I can feel the change in power. So now I am thirsty for more.

Crawford has their cast plenum for $350 and replaces the entire stock plenum.

APS has theirs, but it's $400 and again, replaces the entire stock plenum.

Now I've just found out about AAM and Skunk2 spacers. They run about $225-$270 and seem to be really easy to install. Now I understand that I add another point of failure with the spacer and 2 gaskets, but I like keeping the stock plenum in place.

I figure they all accomplish the same thing by increasing space under the plenum.

So does anyone have an opinion on which one to go with? The AAM is aluminum and angled. The Skunk2 is made of a composite that claims to cool the air.

 

There is also the new line of Motordyne Iso Thermal Plenum spacers.


The new Iso Thermal plenum spacer system combines our aluminum spacer with additional thermal management components that substantially reduce upper and lower plenum temperatures. Cooler intake air temperatures increase air density, reduce the tendency for detonation (ping) and that increases engine power on and off the track.



The Motordyne Iso Thermal (MIT) thermal management components reduce plenum temperatures 36°F - 81°F from baseline. In other words, it takes the plenum from burning hot to just barely warm.



1) The first component is an Aramid thermal isolating gasket that is installed between the lower plenum and intake manifold. This particular material was selected for its unique ability to insulate, its high heat tolerance (550°F) and its ability to resist degradation from oil and gasoline. Aramid’s ultra low thermal conductivity allows the gasket to be thin enough (1/16”) to retain use of 350Z’s strut bar or the G35’s engine cover when combined with the 5/16” plenum spacer.



The VQ35DE’s upper collector (plenum) is bolted to the lower collector (plenum) and the lower plenum is bolted to the intake manifold. The intake manifold is bolted to the hot engine heads and because the intake manifold is a thick-walled aluminum casting, it is very efficient in transferring heat from the heads to the entire upper and lower plenum assembly. And it all gets very hot!



Installing a Motordyne Iso Thermal™ Aramid gasket between the intake manifold and lower plenum, the heat transfer is significantly reduced and both the upper and lower plenum run much cooler.



2) The stock upper plenum uses heated engine coolant at 190°F-210°F+ to keep the throttle body heated. This is to prevent the throttle body from freezing during cold weather operation. While this is necessary for cold weather driving, it continuously transfers a great deal of heat into the upper plenum even when it is not needed. The Motordyne Iso Thermal System incorporates a throttle body coolant control valve that allows the owner to heat (or not heat) the assembly. With local weather temperatures below 55’F the valve is left open. In warmer weather the valve can be closed for maximum performance benefits.



3) The third thermal management component is the new Iso Thermal plenum post spacers. The plenum post spacers are self retaining and self sealing. Their cupped design keeps them in place even if its respective bolt is removed from an installed plenum. They won't melt even at 450°F; which is far above the plenum’s operating temperature. And they have a very low thermal conductance so they don’t transfer heat.


A stand alone Motordyne Iso Thermal kit is available to previous Motordyne customers and even to those who have stock or other aftermarket plenums. It is the most comprehensive plenum thermal management system available. The upgrade will allow both the upper and lower plenum assembly to run much cooler.


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There is also the Copper Iso Thermal option. If you don't want to mess around with adjustments based on ambient air temperature you can get the polarized copper throttle body heater. With that, you dont have to adjust anything no matter how hot or cold it is outside.

In places like California, Texas or Florida temperatures generally don't go below 55' F so the Copper isn't needed, but if you live in temperate climates such as Chicago, Montana or Canada, the Copper Iso Thermal is a good option to take.

So even in sub-zero weather, the throttle body will remain heated while the plenum can run as cold as ice. Its almost like driving with a bag of ice on top of the plenum all the time (but without the mess). And cold air does indeed make a big difference on engine performance.

Here's a sneaky peak at the Copper Iso Thermal.

It works by providing high thermal conductance on one side and high thermal resistance on the other. Keeping the TB side heated and the plenum side cool.

Note: the copper tubing is bonded to the pure copper plate with silver solder for high very thermal conductance. And the black rubber is 1/8" thick Nitrile. Heat doesn't pass through the Nitrile.

Putting all these different thermal management components on the plenum make a big difference.

 

Here is a picture of the throttle body side of the Copper Iso Therm.

This side uses a stock metal gasket and just a very thin layer of the heat transfer compound (on both sides of the metal gasket) for increased thermal heat transfer.

See our website:
WWW.MotordyneEngineering.com
for more information.

Be sure to check out the installation manual for details.

 

What kind of gains are expected from these?

 

Very good gains!

I can't talk about the numbers untill they are published in the next issue of Sport Z Magazine! You will want to see that issue!

 

Which issue?

I think the latest one is Aug 27 ...

 

Well they didn't have it B&N so I am S.O.L until we talk you into posting them.

 

Once the next issue comes out the results can be posted.

 

i'm selling my spacer new in box motordyne 1/2inch... 200shipped (complete kit)

 

You might want to hang on to that spacer untill after the dyno results are published....

You might be inclined to keep it after seeing the results... or at the very least you could get more $$$ for it.

 

thats for the dyno w/ the thermal kit right? i have the original one you made. and i saw the results and was very impressed thats why i bought it but im thinking i might go another route, but let me know what you think. when are those numbers coming out?

 

The spacer tested was the basic kit like you have - without the Iso Thermal. No Aramid gasket and no CCV.

The results should be published in about 60 days. (I know...Its a long time to wait)

 

I know you can't screw the mag over by telling us ... but jeez. I want to move on this now but I have to see results first. Kinda hurting yourself.

Then again ... I have no patience.

 

You asked about options, and mentioned the Crawford. IMO, the Crawford is still the best bang for the buck out there. The Motordyne while it does allow more mixture to the front cylinders, it doesn't equalize the mixture to all the cylinders like the Crawford does. I don't know how this new thermal cooling idea works. But, as far as the Plenum improvement goes, it's Crawford all the way.

Lou

 

how bout the Kinetix plenum?...any good?

 

its a good plenum. keeps intake temps way down (can rest your hand on plenum after a long drive) and allows you to use stock strut bar.

 

What about as far as power enhancement?

 

isn't it about the same as the others, or do you know otherwise?

 

I don't know which why I asked.