Extreme Radiator Ducting: Damian Style: *Pictures*
 

When I first purchased my Rx-7, about 3 months ago. (What a glorious summer this has been) it had no radiator ducting whatsoever. The complete undertray was removed in the suspected addition of a new front bumper.

Not knowing much about cooling theory, I figured that this lack of ducting wasn't really a big deal. A few weeks later I met Andy (GooRoo) and Damian (Damian). I soon learned the potential heating problems I would face if I ever wanted to take my Rx-7 to the track! (For those who don't know, it's nearly impossible for any non-track Rx-7 owner to see Damian's setup, and not instantly want to start tracking their car.)

Long story short, with the help of Andy's "Shop" here in the Twin Cities, Damian designed and crafted a ducting solution for my Rx-7 on the eve before my first track day in Brainerd.

I'll cut to the pictures. I must first say that the car is pre-wash, so she's normally not that dirty.

http://www.bentarnowski.com/rx-7/undertray/first.jpg
http://www.bentarnowski.com/rx-7/undertray/second.jpg
http://www.bentarnowski.com/rx-7/undertray/third.jpg
http://www.bentarnowski.com/rx-7/undertray/fourth.jpg
http://www.bentarnowski.com/rx-7/undertray/fifth.jpg
http://www.bentarnowski.com/rx-7/undertray/sixth.jpg
http://www.bentarnowski.com/rx-7/undertray/seventh.jpg

http://www.bentarnowski.com/rx-7/undertray/1.jpg
http://www.bentarnowski.com/rx-7/undertray/2.jpg

And here is a short movie that gives you a walk around of the ducting.

http://www.bentarnowski.com/Rx-7/undertray/MOV01959.MPG

At first I was really sad when I learned that we didn't have any big Rx-7 shops in Minnesota. I don't feel so bad anymore, because with friendly guys like Damian and Andy, I'm confident that I have more expertise near me then I will ever need.

I'll let Damian chime in with his comments about the materials he used if anybody is interested. Expect the same quality when he starts producing his splitter combo in the coming months. :bigthumb:

-Rotary for the win

Wow, that looks very functional. Glad to hear things are moving forward, Ben. :)

I've been lazy about doing this and need to work on sealing off my radiator better. Good job!

very nice!

Badass. Great job! :bigthumb:

so have you noticed your temps better on the highway?

Great post, video and pics! Thanks!

that looks great!! thank you for the ideal, i'm goin to try that on my seven
Timmy

My temps on the highway are so low that I thought my gauge was installed improperly. I notice a HUGE difference. The only problem is I installed my temp gauges post-ducting, so I don't have a good idea of what my real numbers were before. I'll record some numbers tomorrow on the drive to work.

-Rotary for the win

Here is another pic of her all cleaned up and waxed after my ducting photo session.

http://www.bentarnowski.com/rx-7/waxed2.gif

looks good, I will be doing the same with my v-mount this winter when I install my oil coolers....I just need to find a place that sells aluminum sheets here in AK...

Wow that looks pretty good.

I need to fab something up for my setup too.

Good job! Just think how much cooler things would be if you had a vented hood.

What material did you use? It looks like some type of laminate.

i am deffinatley interested in some details on this. looks Great!

Did you put some foam in the opening on the passenger side where the piping is?

Tim

Great job :)

Great project, I want to do the same!

I have another idea, why not add a piece just behind the radiator down to about the swaybar level to create a low pressure zone behind the rad to help pull air out (see pic)?? Good idea? I saw it in another car's custom ducting project and they tested the temps and it helped.

https://www.rx7club.com/attachment.p...d=127767&stc=1

nice job! looks like you guys got this down pat!

Bad idea. All that will do is create drag and turbulence, not a low pressure zone. By smoothing out the airflow under that area, he's already helped create something of a low pressure zone in the area behind the radiator. You help create a low pressure zone (I say "help", because that's not all that's involved) by speeding up the airflow over the area, not slowing it down.

Well I thought a raised edge would create a low pressure zone right behind it. That's how most vented hoods create a low pressure zone to pull air out, by having a raised edge right before the actual vent. :confused:

Maybe in my drawing it appears too big, could be just a little lip. Besides, the swaybar and related hardware are right there already creating turbulence...

A low pressure zone is created by airflow moving faster over a given area, but there's a lot more factors besides that. The airflow moving over the curvature of the hood (if it's smooth up to that point) is enough to create a low pressure zone over the vent. These vented hoods that have a "raised edge right before the actual vent" are just for appearance.
So then what difference will a "little lip" make if the swaybar and related hardware are already in the airflow creating turbulence?

With a dedicated duct supplying ram air from the front of the car to the radiator a lip under the radiator would be useless for cooling purposes.

My stock front end and stock radiator cool very well with nothing other than fences added to the sides of the nose inlet so that any air entering the mouth cannot escape without passing through the radiator. Cheaper and more effective than just bolting in a bigger radiator as everyone always insists you must.

I experimented with a large forward extending lip as well and it also improved cooling but I don't need it except for the hottest of track days (100+ degrees).

Temps + Muscle
 

These temps were recorded about about 40 mins of highway driving this morning.

http://www.bentarnowski.com/rx-7/undertray/temps.gif

Also, I ran into a little American muscle on the way home. This guy got a big thumbs up. We were only able to play for about a mile or so due to traffic and reasonablness. Forgive me for having to put the camera down to try to catch him! :)

http://www.bentarnowski.com/rx-7/undertray/MOV01968.MPG

My next step is to put up some bug guard type stuff to prevent too much from being sucked into the opening! :)

-Rotary4tw

damn my temps seat at 180 but its also a autometer gauge so it might be off but i'm going to try this ducting tip. thanks man helpfull post

Rotary4tw - i think your tstat might be stuck open or possibly modded with holes.

Hmmm
 

This may be the case. Right now my sender is mounted on the top of the housing, so the readings may not be 100%. I'm planning on threading a new spot down where the automatic sender is located.

I did let the car sit the other night, and watched the temps rise. When it hit 210, the fans came on, so I know it's accurate.

I'm also hopefully installing a PFC this week, so I should have something to cross reference the water temps with.

The oil temps stay pretty low unless I'm sitting around a lot or doing some really spirited driving. The other day in traffic outside the metrodome on a Friday night I was sitting at about 210 d for both water and oil.

I'll keep you posted on the PFC numbers when I get her operational.

-Rotary4tw

IIRC, with a stock ECU the fans should come on around 221 F.

did he mention that I stayed up till 3am making that rad ducting for his car ;-) and about 4 hours later I would have to be going 160 mph around BIR!!!

it was worth it, his ducting is sweet ;-p

I found that in a heating thread. The running lights were on when I was testing so I could use the illumination of the gauge.

I'm going to hook up the PFC and check the spread. If the Defi and PFC agree, I'll leave it. If they don't, I'll tap lower.

-Rotary4tw

here are some more pics I dug up

Ducting looks good....some pretty heinous overspray though....

what material is it made of?

bump for question. Aluminum I guess? Thickness?

i noticed the oilcooler doesnt have a duct? is it supposed to be like that? or did you take it off to get a better look at the rad ducting?

There is no OEM oil cooler duct for 99 spec bumpers, I think rotary extreme's duct is the only option right now.

Looks like Dibond or Alucabond; basically two thin aluminum skins with a hard plastic core. Very light and stiff. It's the same stuff I made my front splitter from years ago.

very nice, where do you get it from?

There are these which help duct the oil coolers for the 99 spec bumper, that is it covers up the space underneath the coolers.

https://www.rx7club.com/forum/attach...hmentid=129230
https://www.rx7club.com/forum/attach...hmentid=129231

Yeah, but I never considered those true ducts... lol gotta love Mazda's engineers

it is not solid aluminum, it is a 'sandwich' material, some type of corrogated plastic skinned with thin aluminum skins. Very ridgid but very light. 1/4" thick.

awesome job... there is NO wasted air. direct to the radiator :D

i think i found a proj for this winter...

looks like a nice job
and a nice car also :bigthumb:

digging up an old thread here... but do you happen to have any sketches or measurements that you could pass along so i have some sort of template to start from in creating my own duct like this?

where do you buy that type laminant material from? i can't find any dealers.

I will be selling them shortly, what type of nose do you have? and radiator?

the lower temps could also have to do w/ the fact that he doesnt have any AC. Usually that sits right in front of the rad obstructing it no?

i have a Sanai Works nose on the way, but will not be installed for a while 6-8 months (better things to pay for than paint right now, but couldn't beat the GB price for the kit), so stocker for the time being. I have a Koyo radiator in it that will be staying put.

please add me to your list of seriously interested persons as i have no ducting for the koyo right now... perhaps i'll just resort to some foam on the sides until the new nose goes on?

can you get links to picture of the nose for me?

i posted a picture of one in your thread about the front splitters (which i'm also interested in, but will have defer purcahasing for a while)

https://img.photobucket.com/albums/v.../7_sanai01.jpg

in the very next post, FDNewbie pointed out that the lower contour is very similar in appearance to the C-West front bumpers.

Those pics are making me want to remove my ac and do some clean ducting myself... Its a complete pain with the ac rad and lines in there though.

think something can be done like this for a FMIC? i have a HKS Type S FM and a Fluidyne upright Radiator. the front mount sits 1.25+-" above the R1 lip and the radiator sits back 6" and up 1" from the intercooler. i wish this was possible, but i think you might need my car to make something like this work. i would like something that is flexible that can actually sit under the R1 lip maybe 1/4" and sit right behind the intercooler. so it can get more air under the intercooler.