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PostPosted: November 26, 2013, 2:08 am 
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So I've been out of the loop here in LocostUSA for a while, some long term users may recognize the name and some may have seen my Locost build log before.
I still have the Locost, haven't made much progress on it since I stopped updating the build log, got very busy and haven't had much time to make significant progress.
Good thing these things don't have an expiration date ;)

So busy as life was and still is, I had a fever, and the only prescription was to get more track time.
My wonderful wife made the suggestion to build another Miata for track use, something that will be simple enough that it could be done quickly enough, I'll get back into the groove and at the same time have a rolling business card to showcase some of the fabrication services that I offer to customers.

I started looking for a very clean example of the 2001-2002 cars and found this one which was subsequently named "Creampuff" for the absolute magnificent shape that it was -
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After a week of ownership it looked a bit lighter -
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And lighter -
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And lighter -
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Eventually, the weight loss program shaved close to 650 Lbs. off the weight of the car from the day I bought it.
That's a lot of weight to take out of a little car :lol:

Coming up, adding some weight back!

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PostPosted: November 26, 2013, 2:16 am 
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Glad to see you back! :cheers:

Nice job on the diet. I have always liked the look of a racing Miata without a windshield. Will you be installing a permanent or removable cover over the passenger side?

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PostPosted: November 26, 2013, 2:39 am 
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Once a good chunk of weight was stripped, I went for some seam welding in key areas of the chassis -
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And fabricated custom low seat mounts -
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Time to put a cage in the car, SCCA production low-hoop style cage, I always liked that setup -
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That is an 18 point cage as opposed the usual 6-8 point job most track car have -
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Just add paint!
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Just 6 weeks after purchasing the car, first day at the track in a car that was far from finished but was already real high on the fun meter -
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A month and a half later the car was armed with DA coilovers from Fat Cat Motorsports, Racing Beat sway bar, a few more small upgrades and STICKERS!!!
Pretty much ready-ish for it's first race (TT) the season opener of the west coast Miata Challenge -
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Getting some air under the tires -
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Took some customers for fun rides -
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One more thing that I took was a 4th place finish with a pretty reasonable time of 2:07.3 at BRP 13CW, not too shabby for the car's first outing with so many new pieces bolted on and nowhere near dialed in.

So, a surprisingly good start for the racing season with a car that is all new and still runs a bone stock engine!
Next, more Miata challenge events and the car getting sorted out.

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PostPosted: November 26, 2013, 2:41 am 
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Driven5 wrote:
Glad to see you back! :cheers:

Nice job on the diet. I have always liked the look of a racing Miata without a windshield. Will you be installing a permanent or removable cover over the passenger side?

Hey Justin!
I'm giving you guys the shortened version of a process that started roughly two years ago, all your questions will be answered in the following post ;)

Moti

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PostPosted: November 26, 2013, 3:15 am 
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Forgot to add, initial weigh in as a track car was 1952 Lbs.
That was without any lightweight body panels, OEM battery and complete wiring still in etc.. lots more weight to shed.

Second race of the season came up quick, didn't have much time to mess with the car but had some suspension changes.
Ended up taking third!
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First upgrade, a little wind deflector, you would be absolutely shocked if you knew how much this little guy helps -
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And then came the third race of the season, first time going to Chuckwalla for me and many of the other competitors (newer track) so it was a good equalizer.
The car got another update to the suspension and a couple other tricks -
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And the results?
First place, woohoo!
My customer took second in the Red car, so it was a good day for Blackbird Fabworx :cheers:
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For the next race, I had some time on my hand to sort out some aero related issues that bugged me.
Started with a couple of NACA ducts that were placed where they would draw some pressure onto the...
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...New removable side cover that Justin asked about 8)
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I also got a CF trunk lid and made some front tire spats before the next Miata Challenge round which took us to the fantastic Sonoma raceway -
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The setup converts back into a two seater in roughly 5 minutes, so switching over for the purpose of fun runs is no biggie -
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Ended up taking 2nd, so another good finish for Creampuff.
This car is quick even with a bone stock engine. The brakes are so good it's just hilarious..

The next event was at Big Willow, where I made some experiments at limiting the size of the opening in the front bumper to reduce drag, but the hot ambient temps forced me to revert back to the full opening to avoid running hot -
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Ended up this day with another 2nd place finish 8)

For the next round I built a prototype aero pod behind the driver's head -
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We went to Laguna Seca so I also had to build a new exhaust system to clear the lower sound limit at the track -
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Show time!
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And the results?
Another 1st place finish!
Yes!

More coming up.

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PostPosted: November 26, 2013, 3:44 am 
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More seam welding, this time it was everything hiding under the fenders -
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Also went for another Miata TT comp with a different organizer, took the wife out for a spin -
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And came back home with this -
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Decided it was time to make the interior look as good as the exterior -
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And then came round 7 of the Miata Challenge, this one was at Buttonwillow -
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Which I ended up in third, good enough to secure the 2012 Championship with one last event still to come.
That is a fine first season for a new car :D

But before the Miata Challenge finale came, Mazda corporate ran a day at big willow as a part of the big rotary annual gathering "Sevenstock" and combined it with the annual all-Mazda track day "Mazfest".
I participated as one of the racers that were giving fun rides all day, and it was very cool.
But the coolest thing was this -
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I got to share the track for a demo session with just a handful of other racers and the two GTP ~700 HP beasts that Mazda dug out of their basement, the 787 and the RX-792P -
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So cool.
Even when babied around the track these things are so ridiculously fast, one of the coolest things I've experienced.. I've never been so happy to get showered by tire buggers and being passed on a race track, haha!

One last round of the MC, this time at Auto Club Speedway -
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At the end, I received my favorite paper weight -
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And STILL, the engine was untouched!
Bone stock everything, ECU, air box, emission crap still on... only the cat was removed to make room for the seat mount.

Coming up, 2013 upgrades!

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PostPosted: November 26, 2013, 7:32 am 
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That is one cool little car. Crazy how light it is. I bet it handles like a dream. Looking forward to see what you have planned for next season.

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PostPosted: November 26, 2013, 9:27 am 
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Yo Moti!
Good to see you back! The Creampuff looks like one hot little Miata, and with the usual high class welding/fab stuff we saw from your Se7en build. Keep us posted on your progress, and welcome home!
:cheers:
JDK

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PostPosted: November 26, 2013, 9:35 am 
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Hey! In another thread, there was a link to pics from Fontana (I think?) that showed a "mad aero" (their words) version of Creampuff... So tell us about the Long Tail???

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PostPosted: November 26, 2013, 10:22 am 
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Nice update Moti. Now we know where you've been. ;)

Glad to hear all is well. It sounds like the business is keeping you busy.

Nice prep work - the new toy looks like a blast. I really like what you've done with it.


Blackbird wrote:
First upgrade, a little wind deflector, you would be absolutely shocked if you knew how much this little guy helps -


That is awesome. I need one of those so bad for the same reason! I'm glad to hear it actually works; that is all of the incentive I need.

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PostPosted: November 26, 2013, 11:16 am 
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So maybe now's the time and this is the place to post this.

It's 32 pages long, but there are some little gems hidden away in here.

http://www.miataturbo.net/race-prep-75/post-your-diy-aero-pics-63769/

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PostPosted: November 26, 2013, 1:02 pm 
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Hi Moti,

nice to have you back!

reading the miata site about splitters,

1. the vertical air dam, this tends to move the air over the car instead of building a high pressure area above the splitter, is this your preference?

2. have you tried putting a lip on the lower edge of the splitter, this will induce even more down force just like the lip on a spoiler?

3. have you got any closed compartments in the nose above the splitter, if so can you cut a hole in the splitter so that air can be sucked out of those areas, thus sustaining downforce as the car approaches a corner and the speed drops off?

4. have you done anything to let the air passing through the rad out of the car, if it escapes under the car you are likely to have a loose rear and then overcompensate with a rear wing or spoiler attack angle that is steeper than necessary?

5. the rear edges of the front wheel arches need to be beveled in and any void behind that edge filled, this area acts just like a motorcyclist hanging the knee out in a corner and causes a lot of drag and also causes air lifted up by the tire getting trapped especially if you have brake ducts blowing air in behind the wheel, just move the edge in about two inches at the bottom, tapering off towards the top of the arch with an even flare back to the door.

6. do you have a low pressure area in the cockpit, does the wind hit you in the back of the head at speed, if so this is taking away some of the effects of the rear spoiler, see if you can duct some air into the foot wells to reduce this low pressure if it exists.

just some observations for you to consider but all in all you have a good show there.

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Last edited by john hennessy on November 26, 2013, 1:13 pm, edited 1 time in total.

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PostPosted: November 26, 2013, 1:07 pm 
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Hey everyone, good to see you all :cheers:
Looking at some avatars it looks like some cars got finished and being driven, great job guys!

2012 ended up with a nice paper weight, but I knew that for the 2013 season I'll have to step it up, mainly because we put a ton of work into the aero of the Red car and that thing has a turbo on it, so things will heat up in the class I'm running.

So for 2013, I decided to keep the engine stock and go for aero, lots of aero, muahahahahaaahhaa!
The first piece I went with was just a screaming deal that sadly you cannot find anymore.
When NASCAR introduced the Car Of Tomorrow they had wings on them, and those were some _really_ nice carbon fiber wings with a Gurney flap slot and everything, made by Crawford composites. Top notch stuff.
Then a few cars went for a flight when the cars went backwards and the wings were outlawed as the cars went back to lip spoilers.
This in turn made all the wings that were now no good pop on eBay for not a whole lot of money, I got mine for a tick over $400 shipped to my door.. should have bought a few more, the word about these wings spread like fire and within a month they were nowhere to be found.

So, got my wing -
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And went to work, mounting the uprights to the chassis and making the setup adjustable for not only AOA but also for height of the wing relatively to the chassis and for rake (leverage) relatively to the chassis -
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Combined with nice big end plates as opposed to the goofy ones that NASCAR used -
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Didn't have time to make front aero, so for the first event I ran it @ 0 AOA -
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Wing at top height position -
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Wing at bottom position -
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2nd place finish this time, with the win predictably going to my customer car.
For the next race, back at Chuckwalla, Creampuff got a nose job, ditching the OEM bumper in favor of a more aerodynamic E-prod style air dam combined with a splitter that has diffusers going into the wheel wells to help cooling the brakes.
Post nose job -
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Since I got my wheel to wheel racing license the year before, I was clear to participate in the wheel to wheel race that day, my very first one.
Formation lap -
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Green flag, go!
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Thing were pretty tight for a while -
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I was being uber-conservative, this is my rolling business card so I wasn't going to stuff into corners and such... remember that as you watch the video :lol:


Ended up 3rd in the time trial and 3rd in the race.
Should have been 2nd in both, but I drove like s**t in the time trial and made a huge rookie mistake in the last lap of the race and basically gave away the position without realizing until it was too late.
Oh well, live and learn.

Next event was at BRP, no major changes in the car other than a slightly larger splitter to give the aero package the balance it lacked on the previous event -
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Actively losing weight from the new splitter :lol:
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Took third in this one.
Then it was time to prep for the MC @ Sonoma which is a track where aero grip is king.
It has no high speed sections and huge elevation changes at mid corner in a number of turns, exactly what my doctor ordered.
Seeing that I worked out the splitter mount the way I did (thinking ahead of time), the internal frame work gave me a solid base to mount this to -
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No fooling around.
Took the car virtually unchanged from the previous year on the mechanical side and proceeded to destroy my personal best lap by nearly 3.5 second with the new aero setup (same tires, same weather conditions) -
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Grip levels where absolutely EPIC.
Ended up in second place with the win going to a pro Playboy cup team Alara driven by that 2013 champ Christian Szymczak... couldn't do anything against that one.

BTW, the front wing was fabricated from a solid Balsa core wrapped in fiberglass.

Coming up, more on the 2013 season.

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PostPosted: November 26, 2013, 1:42 pm 
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Hey John!

john hennessy wrote:
1. the vertical air dam, this tends to move the air over the car instead of building a high pressure area above the splitter, is this your preference?

As seen in the post I was writing while you wrote this reply, yes ;)
john hennessy wrote:
2. have you tried putting a lip on the lower edge of the splitter, this will induce even more down force just like the lip on a spoiler?

No.
It's all about the pressure differential, the splitter is already low enough that it nearly touches the track in high speed sections, if you closed that gap with a lip you'd lose that pressure diff between the top and the bottom of the splitter and lose all the downforce.
john hennessy wrote:
3. have you got any closed compartments in the nose above the splitter, if so can you cut a hole in the splitter so that air can be sucked out of those areas, thus sustaining downforce as the car approaches a corner and the speed drops off?

Active aero not allowed where I'm running.
john hennessy wrote:
4. have you done anything to let the air passing through the rad out of the car, if it escapes under the car you are likely to have a loose rear and then overcompensate with a rear wing or spoiler attack angle that is steeper than necessary?

Not yet, I've been avoiding cutting the hood for reasons that I won't explain at this point, you'll just have to stay tuned for future updates ;0
john hennessy wrote:
5. the rear edges of the front wheel arches need to be beveled in and any void behind that edge filled, this area acts just like a motorcyclist hanging the knee out in a corner and causes a lot of drag and also causes air lifted up by the tire getting trapped especially if you have brake ducts blowing air in behind the wheel, just move the edge in about two inches at the bottom, tapering off towards the top of the arch with an even flare back to the door.

Yep, we've done that on other cars, just haven't had a chance to do mine yet.
This is also one of those things where I'm looking into working things differently so I'm taking my time with forming the plan in my head.
john hennessy wrote:
6. do you have a low pressure area in the cockpit, does the wind hit you in the back of the head at speed, if so this is taking away some of the effects of the rear spoiler, see if you can duct some air into the foot wells to reduce this low pressure if it exists.

Wind is definitely not hitting me at the back of the head, that is a problem that convertibles normally have with the top down since the windshield kicks up the air and creates massive turbulence behind it.
Cut the windshield off and you lose that issue altogether.
I have been playing with an idea that is not unlike what you've suggested, I have some parts laying around that will work for the setup that I have in mind, but TBH it is pretty low down the list of stuff that is happening at this moment.

HTH,

Moti

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PostPosted: November 27, 2013, 2:28 am 
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Took a break from the Miata challenge to attend the all-Miata track event at Laguna Seca.
It's a festival of all flavors, from simples DDs to show cars with shiny chrome in the engine bay to full blown track monsters.
Given that I set Blackbird Fabworx as a supporting vendor at this event, we set out Creampuff and the Red turbo car as two seaters and went on to give fun rides all weekend long.
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Playing on track with Keith Tanner, the passenger in Creampuff is Keith's wife Janel :cheers:
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Creampuff ran double sessions both days without blinking, that's 20 sessions!
What a great event.

Back the Miata challenge, the big willow event was crazy hot with track temps of 145 degrees F!
Not much new on the car. Managed a second place finish.
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And then came the Miata Challenge of ACS.
I've had this idea in my head for a while, making a long tail a-la Porsche Moby Dick... and ACS has what it basically the longest straight anywhere, at least in Miata terms, it's 2/3rds of the NASCAR oval, but with a low powered car that handles well you basically run the shortest line around and keep it floored for 45 seconds or so.
So this had to happen :lol:
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That is a Miata with 140 whp behind me (my car has less than 120 whp), fighting to crack 125 MPH as I'm sailing all the way to 133!
Long tail for the win!
BTW, the Pescarolo that is passing us on the high banking is probably closing on 170 there... :shock:

I predicted that the long tail without the wing might make the car a bit nervous with no wing and the big splitter, and so after a VERY exciting first session in which the car launched itself sideways just about everywhere, I bolted the smaller splitter on.
It was still too nervous, but since I thought that might happen I brought a jigsaw with me and ended up cutting it down to roughly 3/4" and got the car to finally point in the general direction I was trying to go, just not all the time :lol:
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So yes, top speed was awesome, but crappy aero balance in every corner made it hard to put the power down and I ended second here too.

BTW, I built the cage in that Blue Miata, here's what the jungle gym looks like inside -
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Coming up, more action than you can shake a stick at!

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