As everyone knows the FD is a rolling oven.

Sure, it outrolls most other sportscars but it is busy baking everything in the engine compartment. I learned that real fast when I stopped at a wayside in Florida and made the mistake of leaning on hood of my newly purchased FD without an asbestos glove.

I have been re-engineering my FD during the last 6 years and have finally gotten around to addressing the heat in the engine compartment from an exit perspective. So you bought the 2 inch radiator and a big intercooler… due to the lack of exhaust flow out of the engine compartment you might just as well weld a plate over the backsides of both heat exchangers.

Plainly stated: you’ll get no flow if there’s no place to go.

Care to take a guess as to the exhaust speed of the air thru the intercooler?

I asked a bunch of people what they thought the exit speed of the air through the intercooler was at 60 mph. Guesses averaged 30 mph. My opinion was less than 10 mph. I rigged a digital windspeed gauge to the back of my ASP/M2 large intercooler and found my guess was a bit optimistic.

Actual measured intercooler exhaust velocity was 1.5 to 3 mph at 60 mph!

If there is that much constriction in the engine compartment (and I run no air conditioner, power steering or air pump to further impede airflow) is it not surprising that our FDs really are rolling ovens?

Combine the lack of airflow with the 300 degrees hotter exhaust you get from a rotary versus piston engine and the fact that the stock OEM turbo manifold is 22 pounds of cast iron which is just about the most heat retentive material on our planet and you have the recipe for lots of cooked everything.

As you know, fortunately, there are a number of fixes available to promote underhood coolness and powerplant longevity…

I am happy to add to the list.

Introducing : Cool Loovers.



Before getting in to Cool Loovers lets consider the FD hood.

It is aluminum and gorgeous but…

Mazda wrapped our thermally challenged powerplant/system in a BLANKET!

Open your hood, and what do you see on the underside? Yikes, how could they do that… here they build this beautiful light aluminum hood. Aluminum. The opposite of cast iron. Aluminum conducts heat like crazy. Away from the engine compartment! But not with the blanket shielding it. Get rid of the blanket… Let your aluminum hood radiate heat. And no, you won’t burn your paint by removing it.

The other problem with the hood is that there are no HOLES in it.

Unless you are going to drill holes in your firewall to let the heat out (which will allow you to remove your heater) you better either remove your hood or put some holes in it. Of course some of us have bought aftermarket hoods made from fiberglass or carbon fiber that do have holes. Unfortunately carbon fiber and fiberglass are close to cast iron as far as heat retention. Think the opposite of aluminum… but they do have holes which exhaust heat.

They also cost $500 plus and many look, er, homebuilt.

The aluminum hood is just too nice to ditch so it just needs some holes… 74 to be exact and they’d be louvers, Cool Loovers of course.

While I get lots of nice comments as to the “look” I wouldn’t be offering (see Group Buy section) this product if it didn’t produce an additional absence of heat.

Of course I instrumented everything… and learned some things. Properly designed louvered/ducted hoods generally don’t reduce underhood temperature while driving down the road. The reason is that they promote more heat transfer from the coolant and the intake charge. That’s because they raise the speed through the exchanger. The speed through my intercooler more than doubled as it now has more exhaust area through the Cool Loovers. Sort of like a 3 inch exhaust pipe versus the OEM setup. I note a drop in charge air temperature of approximately 10%.

The other major benefit is after you turn off the motor. Normal underhood air temperature measured near the front of the throttle body on a 78 degree day is about 91 degrees. 4 minutes after shutdown that temperature is 195 degrees. 20 minutes after shutdown the temperature is 160 degrees!

And that’s without the insulating blanket!

Most of us pop the hood after a drive to promote cool-down. That works at home but there are many places (work?) where it isn’t possible. That’s where the Cool Loovers earn their keep. With Cool Loovers the temperature only goes to 140 and is 128 after 20 minutes.

Cool Loovers are made from aluminum and are the exact thickness so as to conform to the hood yet are substantial. They retain the supporting hood ribs and are attached with pop rivets. You can leave them as is or paint them if you wish. A friend of mine has a white FD and is going to paint his hood flat black and leave the Cool Loovers aluminum.

Cool Loovers are nicely finished as to the edges, the louvers are cleanly cut, and the rivet holes are drilled. Rivets and clear comprehensive instructions are included. You’ll need a drill, an 1/8th inch bit, some of that 3M Blue Painters tape, a rivet tool and something to cut the hood. I experimented and found using a 3 inch electric cutting disc with a file to dress it up worked nicely. An approximate 2 hour easy job ideally with 2 people so hood removal/replacement and the Cool Loover hood placement is uneventful.

Price is $90 shipped anywhere USA. Offshore orders welcome of course. Paypal exclusively. Please see the Group Buy section.
















Cool it with Cool Loovers,

Howard Coleman
this post and the group buy approved by ryan scott
p.s. see your all at the MRR in a few weeks..

 

Any pics of what it looks like from the front?

 

u know that 'blanket' is supposed to put out any fires that start in your engine compartment....


if it works though... idk...

 

That's great news, Howard. Hood vents and louvres have been proven on racetracks for decades. Do you have exact air speed numbers with the louvres?

 

Sounds like a great idea from a performance, and reliability perspective. I don't think I want to do that to my hood.

 

very nice, good contribution

 

Great idea, but i'm with adam on this one. Not sure if i'd wanna do that to my hood. Maybe i'll just buy a vented hood or something.

 

^^^ Same, I do not fancy taking cutting tools to my hood, if that "cool loovers" were the same color of the hood I might consider it. Also, do you have any numbers?

 

howard, why did you decide to place the louvers so far back? There is a high pressure area in front of the windshield.

 

I recall Jim's (then Brad's, not sure who owns it now ... and no I do not mean Labrick here) track car had louvers that were punched into the hood. I also noted that a notable Cali competition car also had louvers, large ones that went down and forward instead of up and back. Both solutions work extremely well.

I looked into it for about a year in Houston but could not find anyone I trusted to louver my stock hood. Your solution is very attractive. If I wasn't going LS1 I would consider it.

 

This is very interesting. Did you notice a change with your modified hood?

 

What do you do when it rains?We get some heavy rain down here in sc.

 

thanks for the comments/questions...

speed thru the intercooler varied between 1.5 and 3 mph w the non louvered hood.

speed w the Loovers was 5 to 8 mph.

interestly the 1.5 to 3 mph related to whether i was following another car... drafting makes the speed thru the cooler decrease. ditto the 6 to 8 mph of course.

as to the pressure... i believe i located the Loovers at the lowest pressure area. the air hits the nose and bounces sharply upward missing much of the hood surface creating low pressure. the loovers are located significantly in front of the windshield. i do agree the area immediately in front of the windshield is high pressure.

i am not running any rain undershield. i have not had any problem with water in my engine compartment and have run the loovers in the rain for the last 3 months. i recommend the lightest coating of silicone adhesive before mounting which negates any water getting between the loovers and hood. i imagine it would be easy to come up w something if you live in Seattle.

howard coleman

 

looks like the air conditioner vents in my house!

very functional but not very pretty (personal opinion may vary per person )

 

Hmmm...Interesting. I'd like to see them painted on a black or MB car. I'd probably find another hood that needs repainting and have it cut up and completely painted.

Also, are those air flow numbers calculated for a SMIC?

 

I agree that they look like a return register. Maybe if they were molded in and painted it would look better.

 

I'll give you props for creativity to solve a problem for cheap. Nice idea and implementation. Asthetics leave something to be desired, so I wont buy them.. but someone else may have a different opinion. Nice work!

 

why not just buy a vented hood? like amemiya or knight sports?

 

Some people would rather spend the extra $400 elsewhere.



Howard, I think you would be interested in the results of a test like this: http://autospeed.drive.com.au/A_1055/cms/article.html <<The site requires you to subscribe to view the whole article, but it's a pretty simple concept. You basically tape a bunch of yarn tufts on your car, and have someone drive beside you and take photos or video, to determine what the air is doing as it flows around the body of the car.


I'll try to put some yarn on my hood sometime and have a friend take some data.

-s-

 

All the quality vented hoods I've seen are at least 700 and the ones that look decent IMO are 1k+, so this deal makes a lot of sense if I wasnt so picky :-/

 

I think the idea of simple vents is good. But sorry Howard, I'm just not feeling the look of the add-on vents and pop-rivets. I'm not sure how aluminum would take the vents if they were punched directly to a stock hood. The aluminum might tear or warp so bad it wouldn't be practical. But if it could be done, I think I'd find a hot-rod shop to do it, shaping the vents to fit between hood bracing as you've done. I think it would be a good alternate to the fitment and (possibly) cost issues of most of the aftermarket hoods I've seen.

 

For cooling, I think scoot hoods are very nicely designed. it'd be interesting to see how these "cool loovers" compare against other aftermarket louvered/reverse scooped hoods.

 

I will do that test with my n1 hood when it clears up here, interested to see if the n1 hood works the way it should...

 

just some notes, I've taken from howard (2 T04S) coleman

 

Another resurrected post from the past! But a good one. Balancing the inherent good looks of the FD with the practicality of hood vents is a tough one.
My favorite car of all time, the Jaguar E-type, had a beautiful louvered hood. This was a car than in the early 1960s had nearly identical performance, horsepower, and weight as the FD.
And it was noted early on it its development that 160 mph air has to have somewhere to go, and if could aid in cooling things down, so much the better!

Personally, I just can't abide ANY of the vented hoods on the market. Most of them make the beautiful FD pretty much INSTANTLY look like a HOTWHEELS or George Barris-on-acid creation.

Probably a better thing would be to manage the airflow throughout the entire car via a full-body undertray, utilizing effective diffusers at the rear of the car to take advantage of the normal low-pressure created there.

Good stuff that Howard did though for sure!