Cold Air Intake Manifold Insulator Any Good?

[aussie.steve]

I am really new to car modding and are just trying to get my head around the basics.

I am currently on my Red P's, which is an absolute bitch cos of the specific laws.

Anyway i am considering getting a cold air intake manifold insulator for my r31 skyline.

So my questions are:

Are they actually any good?

Is it as simple as removing the upper manifold to install? or do i need other parts?

Are they legal for me on Red p's and what about green?

And are they safe? is there the potential to cause damage to the car/engine?

Cheers

Edited June 29, 2009 by aussie.steve

[SKiT_R31]

It wont hurt the engine, it doesnt got between the plenum and the runners is goes between the head and the runners, so you would have to unbolt the whole intake manifold.

It will lengthen your runners slightly, changing the effects of 'velocity-of-sound' volumetric efficiency gain, making you runners longer, will probably push your peak torque down, by how much though, i dont know, possibly 200rpm.....?

Main change obviouysly is less heatsoak, which is a benefit, but the problem is, RB's have coolant flowing through the plenum, which is hot (~80 degrees) so thats where all the heat is coming from, not the fact that its bolted to your head. Cant reember how RB25's are off the top of my head, but i think they have section coolant flows through which you cant avoid, so there is probably no point adding the spacer. RB30's on the other hand, i always used to remove the coolant lines from the plenum, which would turn a too-hot-to-touch plenum into mildly warm, with a gain in performance & responce after the engine warms up.

Also, cooling the plenum/runners, means your fuel wont atomise as well, colder injectors and colder fuel means more will also be injected, with the end result being increased fuel usage at light throttle/rps/ lower injector duty cycles.

It's all fairly trivial, but for the ~$90 i think the money could be better spent