Indy Car engine cover

[Michael Fling]

Indy cars have a foil of some type on the inside of the rear engine cover. While I believe it would be a nice look inside my SLC, would that be detrimental to heat in the engine compartment? DEI has such a product but my thinking leads me to believe that it would hold more heat?

 

[Scott Rowland]

In theory I guess it would. But your motor would be spaced further off the body work to really need it. If just going for the look, I highly doubt you would notice any real difference in temps.

 

[Dr. David]

I have a similar car with a mid-engine configuration. I lined the rear canopy with a foil mat that is sandwiched with a header-wrap type material. (I assume it is not asbestos, as that causes mesothelioma). My thought was that it was for protection of the rear bodywork. I didn't want heat escaping through the body. As for getting heat out of the engine bay, airflow/ventilation, plus black ceramic coating on the exhaust system are in my mind more important, but I'm no expert.

 

[Mesa]

I think Indy and F1 do that to keep the engine heat from decomposing the body and or the paintwork (actually most indycars are wrapped)

 

[Terry Oxandale]

I recently installed the DEI heavy thermal barrier (transmission tunnel/floor product) onto the underside of the fiberglass body panel just over the headers. An IR thermometer showed about 175 degrees on the exterior of the panel in this area as a peak temperature before the application of the barrier. When I get back in town, I'm going to test it to see what the new lower (hopefully) temperature will be. It is only about 4-5" above the header tubes and collectors, and I'm trying to avoid any blistering of the paint.

 

[Mesa]

Interestingly - The hood on a black car may show 200+ degrees F in direct sun on a hot day.

 

[John]

An IR thermometer showed about 175 degrees on the exterior of the panel in this area as a peak temperature before the application of the barrier. When I get back in town, I'm going to test it to see what the new lower (hopefully) temperature will be. It is only about 4-5" above the header tubes and collectors, and I'm trying to avoid any blistering of the paint.

Interesting. I'm curious what it is on a daily driver after sitting in the sun for a little while. I expect it varies widely according to the color, but wouldn't be surprised if it was in that range on a black car in the sun.

Edit, I see Mesa posted while I was typing. GMTA.

 

[Terry Oxandale]

I initially posted it as 275, and then I thought, surely it wasn't getting that hot, and changed it to 175. I guess I'll find out this weekend when I crank it up and see what the lined side temp is versus the the unlined side.

 

[Randy V]

Some of the new heat reflective foils boast an 80% or more rejection rate of heat and an 800*F capability..

 

[Will Campbell]

This thread is of interest to me, because a recent conversation with the folks at Fuel Safe reminded me that a fire system bottle has to be below 190 degrees F to function properly.

I want to mount a 5 or 10 lb bottle in the rear, with the engine, but am unsure about temps. So i bought some heat-indicating labels (from McMaster) and will be applying them to surfaces that are protected with a shroud and insulating materials. As they change color, they show the max temp reached.

If they stay under 180 or so, I'll be happy, and mount the bottle there. If not, I'll have to mount it somewhere in the interior, which I'd like to avoid.

I have some of the gold foil, as well as the DEI silver, crinkly stuff. I prefer the DEI but will experiment.

 

[Terry Oxandale]

I'm unfamiliar with the SLC engine bay heat characteristics, but mine are abisimile. Fuel temperatures alone reach between 160-180, and that's with it recirculated through the tanks. I've added hose insulation, heat shields around the surge tank, and ducted air from the side scoops and under the car. All of this has helped fuel temperatures a small amount, but the fire bottle had to go into the cooler side pod next to the driver to keep it cool (in a relative sense).

 

[Troy]

Any suggested brand names to look for with this gear? I too, am on the hunt for some. My car has a mix of thin silver and gold coloured mat around the engine, as well as some more solid aluminium stuff that has a perforated surface (this is on the carbon floor, right under the headers).

 

[Terry Oxandale]

So I let everything get nice and hot, without any air flow over the car, and the 175-180 range was read on the un-lined bodywork over the headers. The lined portion read about 115-120 degrees. Very noticeable to the hand. I agree, this is comparable to a dark colored car sitting in the sun, so I don't know that I'm getting any significant benefit, other than I would surmise the underside is probably hotter than the exterior side as I'm reading the temps.

 

[Dr. David]

Not in an SCL, but an idea:
This is a solution for under bonnet temps, but I don't know how well it would work for an SLC. These are three small SPAL 4 inch fans ( 30103009) mounted inside the rear grill. They are controlled by a Flexlite Variable speed controller (31165) and a temp probe. The small box just below the fans is a backup camera and not part of the fans. Note the thermal barrier lining the bonnet that protects the paint of the overlying body. This seems like it would be very beneficial if you got off the freeway and got caught in slow-moving traffic.

 

[Jack]

Wayne has two 5" SPAL fans located on the under tray in proximity to the exhaust
manifolds, blowing straight down. It works extremely well.