Material suggestions for intake manifold 'box'

[ConstantCraving]

I'm thinking of a type of plastic box to surround or place the manifold in to isolate it from engine compartment heat. Race cars use carbon fiber, and that's maybe the way to go, depending on how it's constructed and who's doing it.

I can't do CF, so something in flat panels maybe that I can cut and fit as needed. At least for the prototype. Flat panels could be used in this application.

The best material would be low cost, provide high resistance to heat trying transfer through it, and able to survive long term in an underhood environment's varied operating conditions.

Or, if not flat panels, what type of canned, part A/part B material is suggested? Just Fiberglas?

Any minimum thickness recommendations?

Thanks

 

[GregLocock]

is the intake manifold the same side as the exhaust? If no, expanded polystyrne foam over any old weldable plastic. Failing that, rock wool.



Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[Fabrico]

You can put it in a box, but what will keep it cool? Or for that matter, at least at times, what will keep it from staying hotter than no box at all? Some just use insulating spacers between the head(s) and manifold.

 

[Peter7307]

You might also consider either a cool air duct or a double skinned box ie: a box inside another box with an air gap between the two.
Cheers , Pete.

 

[ConstantCraving]

The intake is on top of the engine.

Insulating spacers are part of the overall plan. At a local cruise a Superformance Cobra had a spacer under the carb...the carb was cold to the touch, the engine was hot enough to fry an egg on.

I can get ambient hi pressure air from the base of the windshield to circulate through the 'box'.

I don't think the intake would still heat up, not with the 'box' encircling the intake all the way around. Except for where the intake runners meet the heads.

Corvette Lemans cars have their intake in a CF or ? box don't they?

With the right material, the heat couldn't get through easily. Do to space restrictions and for a more cosmetically pleasing appearance, I really wanted make a box that follows the contours of the intake to fit like a glove, but with an air gap between the two of course. Could even lay up fiberglas over a manifold I guess, but a material with more resistance to heat penetration would be better.

The intake's not curvy, mostly straight lines so to speak.

 

[larrycoyle]

A couple of things here. You start off talking about an airbox but you don't mention the type of vehicle or the application. There are many materials you could make it from but to start with, and for experimental purposes, I would use the cheapest. Whatever you use, you will be well advised to add some type of heat resistant material to help keep it cool. There are all kinds of material available that come in sheet form and you could insulate from both the inside and outside. One possibility is to look at using a "double wall" construction to help keep the air cool inside the box.

As for spacers, you need to remember that anything you add between the manifold and the cylinder head is basically adding to the total length of the port. Most spacers are placed between the manifold and carb/throttle body. There are also materials available to allow you to coat the manifold further holding down the temp. I would also consider some type of cold air duct into the airbox.

Larry Coyle


Larry Coyle
Cylinder Head Engineering, LLC

http://www.cylinderheadengineering.com

 

[bvanhiel]

Maybe a bumb question... but why a box? Why not just wrap it with backed insulation?

-b