since that last thread about exhaust wraps kinda got swamped about louvres, i wanted to ask if an exhaust wrap is that shy stuff that looks kinda like wut you put in your windshield when the car is parked to keep the sun out. im thinking of doing a custom intake that may not be done in metal tubing so i need somethin to keep it from suffering from high temps but i dont want a big shiny wrinkled aluminum thing sittin right there on top.

 

exhaust wrap is made of woven fiberglass, its usually not reflective but comes in different colors

as far as the material of your intake, tests show that material of the intake has little if any effect on the temperature of the air moving through it. i think it was griggs who had the specs on that test??

 

No specs. The intake has a high heat resistance compared to metal and the air moves very quickly. It's pretty apparent that it's not the big place where the air gets heated. It's the heat coming INTO the intake that is more of an issue.

Hmmm...maybe louvers would help...

It's silly to start a new topic though. You could still have asked this in that one. What difference does it make what's talked about in it, as long as the topic still refers to the wrap?

 

john i could have sworn you had some numbers or a link when we were having the big intake material debate over on GE, do you not have it anymore?

 

I think we use a thermodynamics calculator or something somewhere. You input estimated r-values, flow rates, densities, temps, etc. and get heat transfer numbers. I don't remember at all, that was quite a ways back and I may even be remembering a different problem, lol.

It's all academic -- it just doesn't make that much of a difference in the intake when you're moving, and the engines RPM is up, which is usually where people are concerned about it. Even at slower RPM's, it's not a big deal.

 

 

Stainless steel is better than aluminum (in general)

I think i might have toyed with the calcs and values back in college, dont recall if i ever finished it or found also that it probably isnt that significant.

But I got an SSD and it's stainless

 

im not worried about the temp of the air, well i am but....thats not the reason for exhaust wrap. i was worried about keeping wutever i use from getting heat damage or sumthin

 

lonefx4, i think they misunderstood ya..

bob i think he means he doesnt want the intake tube itself to accidentally melt from the heat of the engine if its accidentally rerouted somehow too close to the engine itself.. wasn't yet asking about temps of the air flowing thru, lol.. that'll be later!

 

well, either way you whether you are concerned with the tube temp or air temp, you are trying to keep the tube as cool as possible. The exhaust wrap keeps heat inside the exhaust headers so they should work at keeping heat off the tube. You would want something light, like a white wrap (not black). Actually a reflective (shiny) wrap would be best.

Basics in thermodynamics: Heat goes from hot to cold. There are three "modes" of heat transfer: conduction (surface to surface), convection (air) and radiation (radiated waves).

Unless the tube is pysichally touching the engine or something hot, your biggest threats of heat are convection and radiation. This is where the reflective material will benefit as the heat will reflect or "bounce off". Some heat will be transferred to the wrap and this is where a good material comes in, one that is not very conductive. Aluminum for instance is a great conductor of heat and therefore is bad in this application. That should pretty much get you started, and may be enough to complete you project. Good luck!