ztube+K&n made me happy. ill prolly leave this setup on the car. the K&N+ztube gave my intake a little bit of a whistle noise at low rpm's when i shift. The plenum spacer and mrev made the motor sound throatier.

installed mrev2+5/16 spacer on my car recently. The different levels of spacer do as follows from user Hydrazine

You want to turn off the valve in the warm time of the year to shut off the flow of hot coolant flowing through the plenum.

The Iso Thermal and Copper Iso Thermal reduce heat transfer into the upper and lower intake plenum and reduces assembly temperature by 30'-60'F. Cooler intake air temperatures increase air density and reduces the tendency for detonation or ping.

There are two major heat sources that transfer heat into the upper and lower plenum.

1) Transfer from the lower intake runners which are bolted to the heads at ~250'F. The lower intake runners are made of heavy gauge aluminum so they transfer heat very efficiently into the lower plenum.

and

2) Heat transfer from hot engine coolant that is coming directly out of the engine at about 200-210'F. This hot engine coolant is flowed through the plenum to insure the throttle body stays nice and hot.

The plenum typically heat soaks to about 170'F. That's burning hot!

A Iso Thermal kit will reduce the whole plenum temperature to about 110' - 140'F. Depending on where its measured, that's basically warm to very warm to the touch.

A necessary component of either Iso Thermal kit is the Aramid gasket. It's installed between the lower plenum and intake manifold significantly reduced heat soak. Basically, the Aramid gasket blocks a major heat transfer source from heat soaking the lower plenum. Aramid is heat resistant and a very good insulator with a low heat transfer coefficient.

To block the two main heat sources, the aramid gasket is used with either:

1) The throttle body Coolant Control Valve (CCV).
The CCV allows you to selectively heat (or not heat) the plenum assembly. With local weather temperatures below 55'F the valve is left open. In warmer weather the valve can be closed for maximum thermal benefits.

or

2) The polarized Copper Throttle Body heater.
Copper Iso Thermal is a set and forget component that is used in place of the CCV. With the Copper, it doesn't matter how hot or cold the weather is. Install it and the throttle body remains heated while the rest of the plenum is thermally isolated. Keeping the throttle body heated prevents ice formation on the throttle body butterfly valve when driving in cold weather. If it snows or gets really cold in your area, use the Copper Iso Thermal so your throttle body remains heated and engine can still take full advantage of the cold air you are driving in.

Note: Nissan (Infiniti) intentionally heats the throttle body for safety reasons. Its to insure the throttle body doesn't get iced up when driving in very cold or snowy weather. And none of the Motordyne plenum spacers run an increased risk of throttle body freezing.


1) The basic spacer leaves the entire plenum hot all the time. (just like stock)
2) The regular Iso Thermal heats the plenum when you need it and doesn't heat the plenum when you don't need it. But depending on weather condition, the CCV must be switched on or off.
3) The Copper Iso Thermal is fully automatic. Just install it and forget it. It always gives the best results without adjustment. But it costs more.

^^basically the last 3 lines here tell you everything you need to know.
Heres link to that thread (https://g35driver.com/forums/intake-...-question.html)
My 1-2 is slightly notchy when i first start the car. Once the gear oil warms up it runs smoothly. I just switched to Motul in the tranny/diff today and it made a drastic difference. 1-2 still sorta notchy(not nearly as much as oem fluid) until the car warms up but once its warmed up its really like a "hot knife through butter". It feels much smoother when shifting then it did before. Also none of that tugging/pulling feeling when driving in 1st gear and letting off the gas. Its completely smooth.

 

Funniest **** I've seen in a long time. Wow..........

 

The z-tube from stillen has better fitment than oem; Stillen has two bends, shaped like an (S) and the OEM has only one bend (J) right before the tb. The reason why the Stillen has two bends is to make sure it clears the A/C lines, because the can/will rub with OEM Z-tube.

 

Hey saw your in MD here is link to a local G club. I know it says National but its for Nations capital. Its a maryland, dc, virginia car club.

https://g35driver.com/forums/nationalgclub-133/