EOI: Kevlar Heat Shields

16bit · Postby **16bit** » Mon Nov 12, 2007 11:01 am

These are not for sale yet so i put it in this section.

I am currently making a mould to make myself a kevlar exhaust heat shield. I was just wondering if anyone here would be intersted (pending the result) in me making them one. It should fit most headers (not turbo obviously). You must keep in mind that it will have a layer of DEI heat reflective matting on the inside as kevlar de laminates at 450 degrees C. Also try to keep it out of the sun as aramid fibres break down in sunlight. a few minutes here or there is not going to make that much of a difference but don't leave it out in the sun for a few days. Anyway I am suspecing prices will be just over 100 dollars but i will have to do an audit of sorts when i am ready to make. What do you guys think?

Also on that note I am currently designing a carbon fibre flat undertray with rear diffuser. it will be of legal ride hight and should increase fuel economy at the least - hopefully a bit of downforce too. It will double as a structual piece between the chassi rails giving emence rigidity. it will also have a kevlar layer so that it won't splinter in the case of an accident (same rules and v8 supercars). probably a fair bit of money for this one but thought i would throw it out there (probably a few hundred more then the fm butterfly brace?

Steampunk · Postby **Steampunk** » Mon Nov 12, 2007 11:22 am

I'm interested in the heat-shield.
You obviously know your stuff, but please enlighten the great unwashed ..... why Kevlar?
I have a carbon fibre (genuine autoclave, quality panel) panel acting as a heat-shield. The closest it sits near the headers is 30mm. CF gets VERY HOT, and I have placed multiple layers of proper reflective heat-shield tape on it, but the other side of the panel still gets very hot.

I'm sure you are fabricating this cause it will look very cool, but will kevlar sustain the heat?

16bit · Postby **16bit** » Mon Nov 12, 2007 12:27 pm

aramid fibres have much better heat shielding properties then carbon fibres. kevlar is just one aramid fibre that works well. They also very good for cryogenic shielding but with polyetheline foam too. have a look at the engine bay of a mclaren f1 and see why it has gold shielded kevlar and not carbon.

adamjp · Postby **adamjp** » Mon Nov 12, 2007 12:44 pm

There is no real difference between CF or Kevlar for the heat shield purpose. The heat resistance properties are related to the resin and the method used to make the cloth into a solid. The choice of resin (common choices are polyester or epoxy) will deliver UV stabilisation if it is necessary.

Having said that, I wouldn't use CF or Kevlar for this purpose - there is nothing to be gained from the expense and complexity.

Steampunk · Postby **Steampunk** » Mon Nov 12, 2007 1:23 pm

adamjp wrote:Having said that, I wouldn't use CF or Kevlar for this purpose - there is nothing to be gained from the expense and complexity.

16bit is offering custom-made items at just over $100 .... I think this is very good value for a bolt-in item.
ACL makes heat-shield panels at $47 .... :roll:

Oh btw 16bit, what engine is it for? I have the BPZE - NA8

16bit · Postby **16bit** » Mon Nov 12, 2007 3:01 pm

engine is normal nb 1.8 which is pretty much the same as na i think.

main reason i am doing it out of kevlar or a composite in general is a test for the undertray. kevlar suits better then carbon and i just love the look. so 50% is a test the other is sex appeal. kevlar just looks good to me. anywho it should be done in the next 2 weeks so i will post pics and all that and the offer is open to anyone who wants one.

Steampunk · Postby **Steampunk** » Mon Nov 12, 2007 4:23 pm

completely agree with you 16bit.
Mounting points between NB and NA will hopefully be very similar.
Have you thought about somehow creating an \"air-gap\" between the insulation material and the kevlar? This would do wonders with heat-transfer wouldn't it?

16bit · Postby **16bit** » Mon Nov 12, 2007 4:44 pm

it would - will have a think a see how to encorporate it.

NMX516 · Postby **NMX516** » Mon Nov 12, 2007 7:21 pm

1red5 wrote:ACL makes heat-shield panels at $47 ....

Yep, and it works brilliantly. I made up a heatshield out of it for my headers. It's certainly noticeably cooler than the standard one. it's also quite easy to work with. I had heard someone on here mention that they had used it to cover a turbo, and I think, had measured results of significant underbonnet temp drops.

Steampunk · Postby **Steampunk** » Mon Nov 12, 2007 8:26 pm

I read one of your posts recently, stating your DIY ACL shield. I have been toying with the same idea for quite a while, but I just don't like the look of it. I'm not fussy. :mrgreen:

Garry · Postby **Garry** » Tue Nov 13, 2007 8:43 am

I had heard someone on here mention that they had used it to cover a turbo, and I think, had measured results of significant underbonnet temp drops.

Carco in the ACT sells a heatshield made from the ACL product to fit the SP. Without it my AC insulation melted, with it installed I've had no melting problems.

Casey · Postby **Casey** » Tue Nov 13, 2007 1:31 pm

Garry wrote:
I had heard someone on here mention that they had used it to cover a turbo, and I think, had measured results of significant underbonnet temp drops.

Carco in the ACT sells a heatshield made from the ACL product to fit the SP. Without it my AC insulation melted, with it installed I've had no melting problems.

I gave someone a demo at Wakefield a couple of weeks ago on how good the Carco heatshield is. After the drive from Canberra to Wakefield we were able to rest our hands (one at a time :oops:

) on the heatshield which was only just warm to touch. The other person didn't believe me until I showed them how....