Cool Article about the 05 SCCA wagons floating around still.. :)

AMileHighLGT hit the main point. The air flowing over the hood, then up the front edge of the "scoop" is accelerated and has a high pressure front. As it goes over the top it slows, creating a low pressure vacuum. At the same time air forced into the FMIC and Radiator are at high pressure. The air is not only being "pushed" thru the radiator, but the extractor is "pulling" it out too.

Another benefit is the high pressure air blowing thru the radiator normally would be forced to exit under the car, creating front end lift. Not good!

And to make things worse Subarus have a hood scoop for the TMIC forcing more high pressure air into the engine compartment, which is fighting against the high pressure air trying to come in thru the radiator, and even more air forced under the car. That's fine if you have a TMIC because we need to cool that puppy down.

However if you have an FMIC that hood scoop on top for the former TMIC is doing nothing beneficial, and it's actually detrimental.

Hence why I swapped hoods.

I should get better cooling thru the FMIC and Radiator.

Better cooling thru the NACA duct >oil cooler because the air can exit out the top in low pressure.

Better cool air thru the passenger Naca duct to the air intake, same reason as the Naca duct oil cooler.

And less front end lift because the air will be exiting out the top.

If you are interested in this stuff I found this book to be really good:

Competition Car Aerodynamics, 2nd Edition: A Practical Handbook, by Simon McBeath The 3rd Edition comes out next May.

As for what I do for a living......23 years law enforcement, street cop, SERT, Narcotics, Detectives...in 2000 I had a crazy idea for a law enforcement internet network, left LE and became an entrepreneur starting my own little company. In 2007 that company was acquired by a Silicon Valley tech company, now I work for them. It's been interesting being a government employee for a long time, then my own boss of my company, then an executive for a SV Tech company..

Now I'd like to be retired and just concentrate on fun stuff, but the fun stuff costs too much for me to retire!

:wub:I seem to recall the last LGT with hood Louvers was ridiculed. I think you'll get a pass

I think anything will get a pass when the answer is - because racecar, for real.

That being said - I think the NACA ducts look awesome and I want them on my car.

I think anything will get a pass when the answer is - because racecar, for real.

 

That being said - I think the NACA ducts look awesome and I want them on my car.

Have a set in the garage left over from trying to add brake cooling $40

Since ya'll are interested in NACA ducts, here's a few thoughts/tips:

For a street car/show car that you want to look pretty I think the APR Carbon Fiber Ducts are awesome looking. Relatively Expensive at $100.

For really expensive NACA ducts check out the aircraft parts sites!

The downside to CF is it's very stiff. That means you need a location that is almost perfectly flat, or the location can bend to shape the duct, because the CF duct is not going to bend to your location. Since my bumper had a slight curve where I wanted to put my ducts, CF was out.

The typical plastic ducts you can get on Amazon/Summit Racing/Pegasus/Racerpartswholesale/Speedway/Vivid Racing/PitStopUSA look ok but they aren't meant for show, just GO. They are relatively less expensive. The plastic is stiff, but you can heat it with a heat gun to soften them enough so that you can bend a slight curve into them to fit your bumper.

I heated mine, pressed down on them against a bench top to put a bend in them, then riveted them to the bumper while still warm/hot.

Mounting: I suggest you buy a used bumper from a wrecking yard to practice on first. That way you can plan different locations, and get actual experience making cuts in the material before you trash your bumper. I used my trashed from the off road excursion bumper and made several fitting and practice holes in it before I attempted my new bumper. If anybody wants my old one to practice on you're welcome to pick it up.

I found a jig saw with very fine teeth to work best. I also used a 3" cutoff wheel for some cuts, but the jig saw was better. There may be some places the jig saw is too tall to get into and you'll need the 3" or a Dremel cut off wheel. You will want to cut from the inside, that leaves the cleanest cut on the outside/visible side.

The duct can be mounted with the flange on the inside, or on the outside. The airflow is designed to work best with the flange on the Inside, so there is a sharp edge on the bumper skin. It also looks better, but only if you make a very smooth and careful cut in the bumper skin. It's easier to mount the flange on the outside though. It will cover up slight mistakes in your cuts.

I took the harder Inside route. For attachment if you mount the flange on the outside you might be able to get by with 3M super heavy duty mounting tape. On the inside you will need to drill and rivet. Using a hand riveter is a pain for that many rivets, I bought an Astro Pneumatic PR14 Air Riveter, it's a great tool. I love riveting stuff now!

Hope this helps.

How big? Might be a good alternative to doing 1.8 brakes on my Miata.

I have the pegusus plastic ducts Gator talks about. If you have a 90 Miata, you might look into a Type R spoiler which comes with brake ducts built in - just add hose to get them to your disks.

http://forum.specmiata.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=44;t=003358;p=0

http://www.rspeed.net/R_Package_Front_Rear_Spoiler_Mazda_Miata_MX_5_p/na00790970.htm

ebay or a wrecking yard would be your friend. If I ever get my Miata Motorsport license package finished, I'll sell you my old one.

So, forgive my ignorance here. What's the theory behind the "reverse" hood scoop?

Here's a pic of the new 2015 Z06, same theory in a production car:

http://blog.caranddriver.com/wp-content/uploads/2014/10/2015-chevrolet-corvette-z06-coupe-photo-637453-s-986x603-626x382.jpg

Well there went every shred of desire to get into racing cars.. At least three sets of tires for one race, and over $6k in gas, f*** that!

 

I'll gladly sit back and read about it though

LOL. I'm glad to provide your reading, but don't let the cost of the 25 Hours of Thunderhill turn you off from it. Remember that is the cost of running a team for 25 hours of racing. A typical race weekend has between 2 and 3 hours of total track time. Some events even less. So the 25 Hours TH is about 12X more expensive than a club race. Or put another way, it costs as much as an entire SEASON of club racing! Well almost, a season has other costs but you get the idea.

A great way to get involved is to go to your local SCCA/NASA/ or in our case in the NW ICSCC club and volunteer for a weekend in one of many duties. You'll get up close and interact with the cars and drivers and start meeting the teams. That way you can see what it really takes and start working out the costs.

I read Go Ahead - Take the Wheel by Dave Gran back in 2009 and it helped inspire me to take the plunge.

LOL. I'm glad to provide your reading, but don't let the cost of the 25 Hours of Thunderhill turn you off from it. Remember that is the cost of running a team for 25 hours of racing. A typical race weekend has between 2 and 3 hours of total track time. Some events even less. So the 25 Hours TH is about 12X more expensive than a club race. Or put another way, it costs as much as an entire SEASON of club racing! Well almost, a season has other costs but you get the idea.

 

A great way to get involved is to go to your local SCCA/NASA/ or in our case in the NW ICSCC club and volunteer for a weekend in one of many duties. You'll get up close and interact with the cars and drivers and start meeting the teams. That way you can see what it really takes and start working out the costs.

 

I read Go Ahead - Take the Wheel by Dave Gran back in 2009 and it helped inspire me to take the plunge.

A good article to help you get started with your LGT - http://legacygt.com/forums/showthread.php/amateur-motorsports-and-you-can-get-involved-you-legacy-199487.html

Haha I'm nowhere near being able to pull the time/expenses off. I work three jobs and spend money like it's going out of style. Once I get it down to one job that pays what all three currently do, I'll have time to start dabbling in these things.

I'll stick to reading your stories for now

Update: I had issues with the 6 speed clutch not being bled enough. I pulled the slave off and did the trick of tipping it up to allow the last bit of air that is trapped to bleed out. I'm still not sure if it's perfect, I'll know after a few more drives.

The oil cooler sandwich plates have a very slight leak, I'll be pulling them off <again!> and redoing the seals today.

My AIM datalogger/dash is not displaying RPM. Something must have loosened or become unplugged during the tranny swap. I'll try to track that down today too.

Once I get those little things cleared up and i'll get back to work on the splitter/air dam and post up some pics. If all goes well tomorrow night.

And I came across this pic of the Snail Performance Time Attack WRX. Another example of a heat extractor hood, but in different locations than mine. It looks like his oil cooler is mounted in front of the upper right radiator, and either power steering or trans coolers in the upper left, which meant modding the grill a lot:

http://www.aforwardmotion.com/wp-content/uploads/2012/10/TravisBarnesWRX-5.jpg

Maybe I should mount my transponder out in front too! Of course in Time Attack he doesn't worry too much about playing bumper cars with Miatas in wheel to wheel mode.

I like that extra aero tape job on the front fog light pockets.

With regards Miatas, I'm adding a pillow to the back of mine. Don't want other cars scratching up my bumper anymore.

I just helped install new stickers on that car today

Sweet! I'd love to spend some time going over that car and talking with those guys!

Ask them if they are still running the AP Suretrac front and rear diffs like it says on their website (http://www.snailperformance.com/time-attack-team.html ) . I just installed a Forester STI 6 speed with the AP Suretrac LSDs , there's not many of us running them.

A few updates and pics:

The AIM dash/data-logger not displaying RPM was a weird non-logical setting in the software. Fixed after a few hours of frustration.

Fixed the oil cooler sandwich plate leak, (I hope!).

Finished the splitter:

.............

The material is Alumalite left over from a sign. The stuff is incredibly strong and light. Most any sign shop has either new or used signs you can obtain the material from. How strong is it? Well, I can stand on my splitter with my full 210 lbs and it barely flexes down!

At the next Test & Tune I'll ask Boxkita or GEX to drive alongside and tell me how much it's bending at 130 mph. If it is flexing too much I'm sure two more APR splitter rods will solve it. You guys in?

Materials:

Used Alumalite sign

Cardboard for original design template

Thin plywood to transfer the cardboard template to a more durable template surface, which Driving Force used on their Router table to cut the Alumalite.

A few pieces of Aluminum angle, flat, and sheet stock for the bracing and the air dam.

Rivets, RivNuts, metric bolts.

Paint. Silicone sealer for the splitter to air dam joint.

To take it on and off requires removing 8 bolts and the two APR splitter rods with quick release clevis pins. It has to come off anytime the car will be transported then re-installed at the track. I will eventually replace as many of the bolts as possible with quick release fasteners like quik-latch mini latches.

And a big shout out to my friends at Driving Force Graphics in Bend who supplied the Alumalite and cut out the splitter for me. They had the left over sign material. Thanks folks!

Next Up: Rear Wing!!!

I'm sure I can mount a camera on the back of the Miata and let you try to catch me. If that doesn't make it quiver, nothing will.

With regards your AIM MXL problems, that's easily fixable be getting the version for this decade - http://www.aim-sportline.com/eng/products-car/mxg/index.htm#main

That screen is huge!

With regards your AIM MXL problems, that's easily fixable be getting the version for this decade - http://www.aim-sportline.com/eng/products-car/mxg/index.htm#main

 

That screen is huge!

Yeah the new MXL2 and MXG look sweet. My next race car will have one of those...but this one works fine in the LGT now!

As for your Miata, I was really hoping the camera car would be a black LGT Wagon

Rather than mounting on the rear, mounting on the side of the chase wagons would work better. gives you less disturbed airflow. We'd have to do it on a turn2 track day so we could run 3 across down a straight. test n tune doesn't allow non-caged cars.

At this point, you have 3 wheel sets, too. So, you could have 3 legit track wagons on track at same time. Put some subie of bend stickers on the side of all cars for advertising shot.

If Gex is up for it, I'd do one more session. just not going to hammer the corners. Don't want to buy another set of bearings.

GEX and Boxkita, both are great ideas. Next March Team Continental will be having another open track day at ORP that I can invite ya'll as guests.

Having three LGT wagons on the track together would be awesome wherever it works out to do it! We could put together a cool video of that...

Rather than mounting on the rear, mounting on the side of the chase wagons would work better. gives you less disturbed airflow. We'd have to do it on a turn2 track day so we could run 3 across down a straight. test n tune doesn't allow non-caged cars.

 

At this point, you have 3 wheel sets, too. So, you could have 3 legit track wagons on track at same time. Put some subie of bend stickers on the side of all cars for advertising shot.

 

If Gex is up for it, I'd do one more session. just not going to hammer the corners. Don't want to buy another set of bearings.

http://www.bawcforums.org/vbb/images/smilies/a_brilliant.jpg

Off Season to Do List:

Design and Install rear wing meeting new ICSCC ST rules. The ST drivers voted to change the rule just for our Wagons! "A rear spoiler/wing may not be wider than the width of the car, not including the mirrors. The wing/spoiler may not extend further rearward than 6 inches from the back of the rear bumper. No part of the wing/spoiler may be above the original roofline. For cars with a wagon-style or a near vertical hatchback body, no part of the wing shall be more than 8.0 inches above the roofline. All wings must be behind the centerline of the rear axle.

<Previously the wing could be no higher than the roof.>

Fix Low Fuel Alarm Light.

Install fuel level gauge and sender in fuel cell.

Install Whiteline rear adj. LCAs.

Design and Install fresh air duct for rear diff cooler. Include option for the trans cooler in case I need that too.

Install AP Racing front brakes.

Consider AP Racing rear brakes.

Possibly replace driver seat. It's technically out of date by FIA standards.

Install secondary hand held fire extinguisher. My off track experience proved it's good to have something besides the full monty built in system in places likely to have a grass fire under your car.