Heat Shield Plans???

[Luke240z]

I live on the Sunshine Coast in Australia ans through the Summertime it gets really warm. I'm talking up to 35 degrees celcius. Now engine cooling is not a problem as I have twin 11inch thermo fans on a re-cored radiator. My problem is severe engine power loss from extreme heat coming from the extractors. When I first start the car in the morning and drive to work it is very responsive until the engine gets warm then I think the webers start to suck in the hot air and the power is lost.

I am looking for plans to make some sort of a heat shield to reduce the heat drawn in from the webers, or other ideas to help me with my problem. I have thought about the hot coated headers idea, but looking for something a bit cheaper.

Thanks

Luke

[hls30.com]

This is what I am using for the non-stainless parts of my exhaust.

Black Satin found here:

http://www.caswellplating.com/aids/techline/index.html#exhaust

I am applying The Black Satin inside and out.

Less money, same performance-don't know what it would cost to get to your side of the pond though!

Will

[g260]

Luke,

I am looking at a heat shield at the moment. I am doing two things to reduce the heat. One is to wrap the headers with heat wrap and then I am going to install a drip shield under the carbs and attach a layer of heat shield to the underside.

I have triple 45's and if you look underneath in the middle of the carb towards the front just in front of the 4 screws that attach the bottom plate there is a small stud that screws into the body of the carb.

I have removed this stud (it just screws out) and am going to make a plate to size and attach it to the bottom of the 3 carbs with bolts into the threaded holes where I removed the studs.

A friend has done the same with his Z and it seems to work OK.

Geoff

[Bambikiller240]

Many people have discovered that wrapping headers (extracters) causes them to rust out quite rapidly (2-3 years). The wrap traps water quite well and allows it to do it's deed very efficiently.

A better alternative is to have the headers coated by Jet Hot or another process. The headers will routinely see temps of over 1300 F. so make sure you select a coating that will withstand at least that temperature or higher.

US Website: http://www.jet-hot.com/

Aussie Site: http://www.jet-hot.com.au/

[hls30.com]

The rust issue is the reason I am using a coating-except with a turbo, 1300F will not be high enough, The Black Satin goes to 2000F.

Black Satin (BHK)

"Black Satin is the most advanced exhaust system coating available

Withstands 2000f temperatures

Easy to apply ceramic reinforced coating designed for high temperature applications

Reduces underhood temperatures, reduces exhaust manifold surface temperatures

Improve exhaust gas velocity, increase H.P. Air drying, requires no baking"

Will

[Bambikiller240]

Caswell's product sounds good if you have (as you do & I don't) the equipment to apply it.

Jet Hot makes coatings that withstand up to 2450 F.

http://www.jet-hot.com/pages/headercoatings.html

For my L24 I bought a "ceramic" high temp paint that claimed 1300 F protection and it burned off in 1000 miles. Very unsatisfied with it.

[Aussie Zed]

I've also thought of using a good heat shield too, having the intake on the same side as the exhaust can't help things. I think i found this photo on this site, which shows a good clean design for a heat shield (orange car). This looks pretty effective, but as an alternative a cold air box could be used.

If anyone has done up a drawing or has a photo of a heat shield that they've used out of the engine bay, i'd love to see it!

I've attatched these two pics, i think they're both from the gallery here, but i don't know who's they are . Sorry for using without asking permission.

[hls30.com]

Carl,

Because the Caswell product is water based, All "we" need is a sandblaster, brush(granted the disposable spray can might give a nicer finish-but with a waterbased material, I can't imagine humidity would rear its' ugly head), a sponge. and some twine. Surely within all of the questionable content of your garage, at least part(if not all) of that coud be found there! If not, you have a PM.

Will

[Ed]

If you have the time fabricating a heat shield is easy work.

First make a template out of a cardboard that is as thick as the sheetmetal you intend to use.

Then transfer it to your sheetmetal. You can also take it to a sheetmetal shop and have some beads rolled into it or some flanges to give it some sturdiness.

You can apply a heat reflecting material to the underside if you wish. But the shield shouldn't cost more than 20 bucks and an afternoon with some sheetmetal shears. And it will be a custom job!

[Bambikiller240]

Carl,

Because the Caswell product is water based, All "we" need is a sandblaster, brush(granted the disposable spray can might give a nicer finish-but with a waterbased material, I can't imagine humidity would rear its' ugly head), a sponge. and some twine. Surely within all of the questionable content of your garage, at least part(if not all) of that coud be found there! If not, you have a PM.

Will

My garage is quite basic (except for the "special toys") No sandblast equipment.

[Deus Ex]

Heat shields are very common on Japans Yahoo Auctions, if you can find a nice cheap wat to get them here...

[ZIII]

I've also thought of using a good heat shield too, having the intake on the same side as the exhaust can't help things. I think i found this photo on this site, which shows a good clean design for a heat shield (orange car). This looks pretty effective, but as an alternative a cold air box could be used.

If anyone has done up a drawing or has a photo of a heat shield that they've used out of the engine bay, i'd love to see it!

Attached are some pictures of my system. What I did was rather simple, two stainless steel sheets sandwiched in between is a sheet heat shield made of the same material as a header wrap. Then I riveted all together and built a metal brace to support it. Works great and I have no cookoff although I should mention that my headers are ceramic coated and I am sure that helps also.

I saw an interesting device which was a tube running from the fresh air vent in the radiator support to underneath the carbs. The fresh air vent on the driver side had been disconnected. This tube ran directly below the carbs but it also had a fan, similar to a computer fan, which was hooked up in the middle of the tube. Very interesting but probably overkill.

Anyway, the shield is simple enough and I hope this helps….

George