Penny-pinching car geek's guide to racing, track days, and car build. DIY projects, product reviews, and interviews.

Thursday, February 17, 2011

Choosing rental kart venues



Driving is like a drug.  Since my track event on the 5th got canceled, I just had to find something to replace the experience.  After researching some options, I decided to go to Ocala Grand Prix to try out their rental karts and check out the track.  I chose OGP based on my experience at Miramar Speed Circuit in San Diego.  I used to frequent this track chasing laptimes.  

MSC is a 1/4 mile indoor circuit.  Its a real tricky circuit.  The karts are Sodi karts with crash bodywork, with some sort of 4 stroke motor that probably puts out 4-5 hp.  They were plenty fun.  The karts were beat up though, so some karts are slightly faster than another kart.  As with most rental karts, these karts understeer a little bit.  But that doesn't matter. With karts, its very easy to use weight transfer to modify the behavior of the kart.  If you live in San Diego, I highly recommend it.  The last time I went, they still had two-for-tuesdays, where you pay 23 dollars or so for a 20 minute session.  Its a good deal and you can really work on your driving there, hassle free.

Why am I talking about Miramar? To put it into perspective.  Ocala GP had the same Sodi karts, but better maintained and not as beat up.  Furtermore, they ran 4 stroke 9hp motors! Thats about twice the horsepower.  And of course, the 3/5ths mile track is much bigger than the indoor track.  It is also plenty wide so you can choose between several different lines.  Lastly, the surface is much smoother and the tires are slightly grippier. This was pretty serious for rentals.  Now, for the most important part.  The cost: 14 dollars for a 10 minute session.  I spent 42 dollars to do three 10 minute sessions.  Lets put that into perspective, based on other experiences I've had:

1. Miramar Speed Circuit 23 dollars for 20 minutes. 
10 minute cost: $11.50 (On Tuesdays)
Kart: 4-5hp Sodi rentals
Track: 1/4 mile indoor, pretty good for an indoor track.
I go to this track almost every time I visit San Diego.
2. Moran Raceway 225 dollars for 50 minutes
(I can't remember the exact costs and time)
10 minute cost: $45
Kart: ~20hp HPV kart of unknown brand
Track: Probably the best karting circuit in the country, with elevation changes and blind corners
Unfortunately, this circuit shut down a few years back.

3. Ocala Grand Prix
10 minute cost: $14
Kart: 9hp Sodi rentals
Track: 0.6mi outdoor, no elevation changes

All three of these places are or were very good deals, and I would pay to go gladly.  In my opinion, Miramar tests your technical driving skills, as well as forcing you to move your hands quickly.  It was also great for wheel-to-wheel practice, because the track is often crowded.  Moran had every element imaginable.  But I really liked Ocala GP.  I had a lot of fun there.  In my opinion, the track tests your car control abilities more than anything else.

I almost always choose things for value.  In other words, what gets me the most seat time for an acceptable quality.  Sure, the HPV kart is the quickest and most fun, but if I do that, I can only go a few times a year.  I can go to an indoor place, but most indoor places (Miramar Speed Circuit being the exception) offer too little seat time for too much money.  A place like Ocala offers reasonably fast and fun karts that run pretty consistently kart-to-kart.  Perfect.

Dustin about to head out
When choosing a kart rental venue, take these things into consideration.  I place heavy emphasis on seat time and seat time quality.  OGP had a great seat time to price ratio, especially given the speed of the karts.

We arrived around 6:30pm.  Another thing I like about this track is that it is open late, until 8:00pm.  Thats pretty awesome for north central Florida, where everything closes early and frustrates the hell out of me.  It also makes me wonder: do people actually want money around here?  It is well lit also.  After signing in a waiver, borrowing neck braces free of charge, we went straight to the paddock area.  They also have rental helmets but we brought our own. 

We went on a Wednesday and the track was pretty empty.  There would be 3-4 karts on the entire track.  I think up to 8 are allowed.  I also later realized, even with a full grid, there is plenty of room to drive at your best and get a clean lap in, while you get to draft people in front of you.  I also brought my data logging equipment.

I spent the first session learning what the track looks like and got used to the kart.  Getting used to the kart was easy; they drove very similar to the Miramar karts.  I figured out the lines to most of the circuit, and had a general idea of how to drive it.  Also, I figured out where I could go flat out without lifting.  I think my friend Dustin spent time getting used to the kart.

My second session, I really started working on hitting all my apexes and pushing things a bit more.  I figured out that I don't have to brake most of the track.  The grid was full, so I got to spend some time trying to pass people.  That was a somewhat novel experience for me.  I haven't had to pass people on wide open outdoor tracks very much.  I got my fastest time here: 41.9 seconds.

Me striking a very corny pose
My third and last session, I was alone on the track so I really got to work on my driving.  There is a turn that is very critical which leads to a long straight where you want to carry as much speed as you can.  To do this, you had to pitch the kart around and increase your slip angle, and "four-wheel-drift" out of that corner.  It was tricky but I got the hang of it.  I have to check my data to see how much it had helped, though.  My best time here was a 42.1, but I was much more consistent throughout.  




Analysis
My fastest time was not the result of drafting; it happened at a clean lap I got in with no traffic.  The northeastern most turn is critical; you don't need to brake going in to the turn prior to that. Just lift, and be very smooth, get around the corner starting out wide, and get on the gas as early as possible.  Every time I went around this I applied Bonilla's "focus on the slowest part of the turn" principle.  

But the most critical turn is what I believe is a right hander called the "oak."  This is the turn that you make after you make the above turn, the left after that.  Pitch the kart in, get on the power early, neutral drift all the way out.  

The big left hander is flat out in the rental karts.  Hit the apex so you have more room to accelerate out.  Use the entire width of the track.

Anyways, the track record is in the 38's, and on this track the hotter it is the faster it gets.  The karts see over 1.5Gs of lateral acceleration, spiking close to 2Gs sometimes.  All in all, if you haven't been I highly recommend you try out options similar to the above ones.  If you are local, be sure to check out OGP!  Wear long sleeves or a jacket, and jeans for safety.

Tuesday, February 8, 2011

Current State of the Broke-Core LOHP Miata project

Whew. I've had so much to post nowadays.  I have many planned posts but I haven't gotten to them yet.  I now have two interviews pending, both of which I haven't written questions for.  I have the beginner how-to-guides that I promised, also which I haven't written anything for.  I was also a participant in an endurance race recently, and I haven't made a post about that yet either.  I have very near-term projects happening soon; I'll have to get to them as they happen.  I also have more testing to do to gather more data for the vortex generators I tested previously.



Anyways, lets recap whats been going on with the project and a short update on my life.

First of all, as you may have gathered, my winter job plans got canceled.  So I had a lot of time to work on my car.  As a result of that, you read that I finished my aerodynamic projects that I had planned, with the exception of the undertray.

Project goal recap
I don't know if I've ever made a post about this, but my goal, with sub-goals I've made such as my failed project OLDAZENIS, was to be the first sub 130hp car to attain a laptime of 59 seconds, without spending more than the overall value of my car.  Also, all of the mods must be able to be performed by the average enthusiast, or else the professional labor must be added into the cost.  And finally, power mods are discouraged as I need to keep the car sub-130 crank horsepower.  I am nearing the conclusion of that project, with the following planned mods. Wheels and tires included.

Right now, Grant's low time in my car is 61.3 seconds. My fast time is 62.1 seconds.  Can I make it? Lets see.

Major upgrades
I got new wheels!  I've been hunting for a good deal and a local enthusiast forwarded me a killer deal.  The wheels are going to be wearing Hankook R-S3 tires, which I chose for excellent grip and wear characteristics.  Even when it comes to tires, we gotta keep it Hi-Kick right?  With this new wheel and tire setup I should come pretty close to my goal.  A bit about the wheels and tires; the wheels are 1st generation 949 Racing 6UL wheels.  The wheel is 8 inches wide, which is an inch wider than my previous wheel.  That means whatever tire is going on there, it will have a better contact patch than if it were going on 7 inch wide wheels, as long as the wheel width is not greater than the tire width.  The tires will be 225mm wide.  Although a 9 inch wheel is more ideal for that tire width, I want to have the option of going back to a 205mm wide tire in the future, so these wheels will do. Incidently, either my R-package 14x6" hollow spoke wheels or the Konig Rewind 15x7" wheels will be up for sale.

My previous wheels are, despite being an inch narrower than the 6ULs, about 3 pounds heavier.  Also, although the RT-615s were 205mm wide, they are a pretty heavy tire.  But so are the R-S3s, especially since they are 20mm wider than the Azenis.  I am hoping the new package is similar or lighter in weight so my painfully low horsepower car will not have any acceleration penalties.

I have also purchased a 2D wing.  By 2D, I mean that the airfoil profile does not change throughout the entire width of the airfoil.  There are a lot of "crap" wings out there without any substantial development, but I think some of them can work well.  Even if they are really bad, as it is an actual airfoil and not just a panel, it should produce less drag and more downwards lift than my spoiler.  Plus, they will work much better with the Airtab® Vortex Generators.  I am really looking forward to the design.

Help fund my project! Stuff for sale
I also have a lot of excess materials up for sale.  I also have another spoiler design that I ended up not putting on my car for sale.  It actually works better than the one I have now, and will look much better on a car with a flat trunklid.  I'm thinking F-body mustangs can really use the rig.  If anyone is interested, please email me at the email address I have on the "about this blog" section on the right sidebar.

Please help me fund my project! As a gesture of gratitude for you reading this blog and parts, financial, and information support you readers give me, I keep no secrets and any projects I do will be published here.  You can help by making a donation of 4-5 dollars or more.  I will send you a waterproof vinyl decal.  Please check the "donate to Hi-Kick Racing" section.  I may be selling T-shirts in the future also, with FAST=CHEAP slogans on the shirts. Details can be found here: Hi-Kick Racing Gear

Personal life
As for me, my last semester ended with some mixed feelings.  I felt I didn't study all that hard, and on the class I did study hard for (mergers) I felt that I bombed the test.  Turns out I'd answered an entire question wrong and applied the wrong analysis.  I had been working hard to get good grades because my grades from my first two years were below average.  I was worried about this semester.  Winter job got canceled, and though I gained a mentor from my California trip, I hadn't gotten any further in getting a job.  But a few days go, grades came out.  I did just as well as my previous best grades, and I scored slightly above average on mergers!

I have also been working on some business ideas. It'll be on the web, and it is for car enthusiasts, so I hope you all stay tuned.  The service will be free or near-free, and I don't actually expect to make that much money from it.

Summary and budget
Modifications (some came with the car)
1992 Mazda Miata with hardtop
- Fuji Racing 8.4lb flywheel
- RX-7 AFM with hack inlet mod and resistor tuning
- Mazdaspeed comp exhaust
- No power steering (not sure if it was removed or didn't come with one)
- Automatic transmission radiator
- Cat converter removed, test pipe in its place.
- Hard dog hard core rollbar, double diagonal with harness bar
- Ebay coilovers (Toyota Celica labeled 2" coilovers)
- Bilstein R-package Shocks (mild machining work included)
- 1999 Mazda Miata front sway bar with heim joint endlinks
Aero:
- Splitter and Spoiler
Tires
- 15x8 6UL wheels
- 225/45/15 Hankook R-S3 tires

Weight loss:
Passenger seat removed
Sparco Sprint seat with custom seat mount
AC removed, Cruise control removed
Soft top removed
Factory undertray removed
Rear sway bar removed
Slight rear bumper cutout
Rear bumper cut out

Soon to be added
Replacing spoiler with rear airfoil
NB tophats for more suspension travel
1.8l brake upgrade

Total cost of mods added: $ 1335. After airfoil, tires, the price will be close to 1600. This is presuming my excess material from projects are being sold.  I have about 400 dollars left to spend.  Not really, but I won't spend any more than 400 dollars and try to achieve my goal.  Some other options I have is adding headers, offset upper control arm bushings, and better bumpstops.

Testing
Some of the testings I've completed, but have not posted about are as follows:
-Tufts testing with Vortex Generators and Rear spoiler
Some of the testing I am planning to do are as follows:
-Intake temperature measurements utilizing airflow from high pressure zone at the trailing edge of the hood
-Tufts testing with and without spoiler, with spoiler at different angles
-Tufts testing with airfoil

Please follow me on twitter!

Saturday, February 5, 2011

Better vs. Worse. - Happy Lunar New Year!

Its lunar new years. Being from Korea, and married to a Vietnamese woman, I celebrate lunar new years.  I'm at the in-laws right now.  I went to temple, ate good food, and had a relaxing time with the family.

A week before today, I had forgotten about lunar new years.  I was just worried about my brake pads arriving on time for the track day today.  When my wife reminded me of the family occasion, I was instantly depressed.  I'd been looking forward to the track day for the last month. I also wanted to see how close to my target time I could get.  I also heard today that Randy Pobst, the World Challenge driver, was at the event also. Double depression.

I needed to get my fix in. I did some research and decided to go Karting next week.  Turns out Ocala has a pretty well-used half mile track with 9hp rentals. Not bad! Good compromise between paying 200+ dollars for a piston port kart and going to GRRC.  Depression gone.

For those who have been waiting for the track day report, with results with my new mods and such, I apologize. But here are some videos for you to watch instead.  My driving and Grant's driving compared.  Grant isn't driving to his full potential, and the video isn't from my fastest session either.


Twitter!

I realized that I can share my momentarily entertaining rants with the world! Please follow:


http://twitter.com/#!/hikickracing