Well here are the weights according to my trusty scale:

• Stock brackets (this bar reuses the stock brackets):  14.6 oz x2
• Endlinks:  7 oz x 2
• Arms:  34 oz x 2
• Bushing Mounts:  6.3 oz x 2
• Bar (1.25″ hollow):  7 lb 15 oz
• Hardware:  8 oz

So the total weight comes out to 16.2 lb.  This is significantly lighter than the Gendron, and just a little heavier than the Ankeny/ ARE bar.  Here are all the S2000 sway bar weights I’ve measured:

And by the way, yeah I have all three bars in my garage.  Which one am I currently using?  The Karcepts one.  It’s pretty awesome.  More on that later.

The post Karcepts Sway Bar – sway bar weight comparisons appeared first on Caserta Racing: STR S2000 Tech.

I had the opportunity to write a review over at The Review Squad about it, figured I’d link it here.  Did a nice little table of all the Viair compressors if you want to get something that fills tires even faster.  This one will do my normal fill job which is something like 30 psi to 35 psi in a 255/40/17 in something like 20 seconds.  Really useful for someone who’s racing and sometimes you can need to fill in a hurry.

Here’s the link:  Best Tire Inflator review at the Review Squad

Viair 70P

The post Best air compressor for autocross: Viair 70P appeared first on Caserta Racing: STR S2000 Tech.

Well here are the weights including all brackets, hardware, etc according to my insanely accurate scale.

Gendron Bar:  19.5 lbs

Ankeny Bar:  14.75 lbs

And there you have it folks, the Ankeny is quite a bit lighter by almost 5 lbs.

BTW, I have an updated version of this post including the Karcepts bar.

The post Small Fortune Racing (Gendron bar) vs ARE blade (Ankeny bar) sway bars: Which weighs more? appeared first on Caserta Racing: STR S2000 Tech.

For STR, you really want a nonstaggered setup with 9″ wide wheels all around.  The rules allow 9″ wide wheels, the S2k can fit them, therefore…max out the rules man!

From here you have a choice of 17×9 or 18×9.  You can go 18×9 and that is totally valid and can be just as fast, but you’ll save a lot of money on tires and generally have a few more tire choices by going 17×9.  Therefore, that’s what all the most competitive cars do.  So I’ll focus on 17×9 wheels in this post.

In order to make a wheel like this fit in the front, you need a pretty specific offset that’s not that easy to find.  That offset is somewhere in the +58 to +65 range.  +60 or +63 is the ideal.

So here are your choices:

TR Motorsport C3 

These wheels are absolutely your best bang for the buck outside of used wheels retailing at around $170 each.  Weight is 19.2 lbs which is not the lightest of the bunch but it’s not very heavy either.

TR Motorsports C3 Light Grey

TR Motorsports C3

TR Motorsports C3 Silver

Enkei PF01

These are one of the lighter cast wheels at 17.3 lbs and are a great choice.  Price is on the mid-high end in the ballpark of $300/wheel.

Enkei PF01 White

Enkei PF01 Black

Enkei PF01 Silver

TSW Nurburgring

These are a solid mid-range choice at a price of $230-ish and a weigh about 19 lbs.  The finish is a bit delicate but they are great looking wheels.  The bronze is a unique color…very dark, like a mix of gunmetal and bronze.

TSW Nurburgring Matte Gunmetal

TSW Nurburgring gunmetal machined

TSW Nurburgring Bronze

TSW Interlagos

Similar to the above, a mid range wheel that’s a bit lighter than the Nurburgring at about the same price as a Nurburgring.  Weight about 18.0 lbs.

TSW Interlagos Silver

TSW Interlagos Matte Black

Volk CE28N

Now we’re in the baller stuff.  This is the lightest currently available wheel.  14.8 lbs.  Costs a pretty penny though.  Other colors are available, I’m just showing bronze here.

Volk CE28N

Volk RE30

Or another baller option, the RE30.  The weight is similar to the CE28N, I don’t have an exact weight on them (post in the comments if you do!).  Other colors are available, I’m just showing bronze here.

Volk RE30

Volk TE37

Another expensive option, and these aren’t really any lighter than the lightest cheapies, so the only reason you’d use these is if you got a deal or just really like them and Daddy Warbucks is your dad.

Volk TE37

Volk TE37 White

 Advan RSII

These are kinda pricy but not to the extent of the Volks at $2240-$2415 per set.  The weights are fairly light but again nothing like the forged wheels.  They weigh 17.6 lbs.

So that’s pretty much it.  I’m sure there are other Volk options but at least on the cheaper side of the spectrum that’s all that’s available.  There are some older discontinued wheels that are really great too, I’ll go over them in a future post.  If you know of other wheels to add this feel free to list in the comments!

The post What are the best S2000 wheels for STR?? appeared first on Caserta Racing: STR S2000 Tech.

The reasons for shaving a tire are either:

1)  Because the tire is slower with full tread.

and/or

2)  Because the tire will “heat cycle out” before running out of tread anyway, so you might as well get the optimal part of the tire.

and/or

3)  Some tires will chunk or blister when racing on full tread

In summary, none of these are a significant issue with the Dunlop Z2 when racing.

Heat cycling out is when a tire will only undergo a certain number of heat cycles, or times that it gets hot, before undergoing compound changes that make it harder and slower.  Some tires end up getting slower before using their full tread.  Some are more durable chemically and usually go through all their tread before this starts to happen.   In my testing, the Dunlop Z2 does not heat cycle out, even when used unshaved and run all the way down to the cords.

And as for whether it’s slower with full tread, my testing has also shown that the tire is not slower with full tread.  I’ve run back to back tests at a few sites where I compare bald Z2’s (not shaved but just worn out) with lightly used Z2’s, and the times are identical.  The one caveat to this is if you have a lot of gravel/broken up-ness, or obviously water.  Then more tread actually helps.  But at most national autocross sites with good quality pavement/concrete, or in the dry, they’re pretty much the same.

This proves that both 1 and 2 above aren’t an issue.  Also I experienced no chunking or blistering so that takes care of 3.  They are a bit different in feel.  There are pros and cons to each.

• Very low tread Z2’s
  • Feel very direct.  Awesome feedback.  No tread squirm
  • Are less forgiving to excessive slip angle
  • Will be slightly lighter due to less tread.  We’re only talking a pound or two per tire but…this is autocross we’re talking about.
  • Seemed to not get overheated as badly, I think both because they had less rubber to heat/cool and because the water I was using between runs was more effectively cooling the rubber.  But this was a small difference.
  • Horrible in rain.
• Full tread Z2’s
  • Are more forgiving
  • Seem to have just slightly more ultimate grip although it’s not enough to really be able to tell from the data if that’s the case
  • Have some tread squirm – need to turn a bit earlier and look ahead more
  • A bit harder to manage temperature in the heat.
  • Don’t have to worry as much about rain, since you can do very well without having to change tires
  • Seem to be better on looser/rough surfaces, but how much is debatable, haven’t done really objective testing here.

But at the end of the day, I was running the same times with each.  The bald ones were a bit more consistent in terms of having no bad runs, but the full tread ones the flyer runs were just a hair faster (like a tenth or so if I remember right).  This testing included Lincoln NE, the home of the autocross national championships.

One thing to keep in mind with the Z2 is that they do need to be scuffed in to be absolutely ideal.  Something on the order of 5-30 autocross runs will do it.  But shaving doesn’t seem to change this requirement, even if you have to shave you still have to scuff in.  The full tread tires above were scuffed in.

So in summary, you don’t need to shave Z2’s to win, at any level.  But I could see some people doing it if they really value how the tire feels at lower tread depths.

The post Tire choice: Does the Dunlop Z2 need to be shaved? What tread depth is best for ultimate grip? appeared first on Caserta Racing: STR S2000 Tech.

She knows what she’s talking about

Step 1:  Get your car into good shape

Absolutely the first thing you should do is make sure the car is in good running condition.  One of the biggest things to check is the bushings – make sure they’re in good shape.  If any are bad, replace.  Also check the tie rods and ball joints.  Pry at the arms around them lightly with a pry bar to make sure there’s no play and make sure the boots aren’t ripped.   Tug on everything in your suspension and make sure it doesn’t move in ways it’s not supposed to.

That all sounds obvious but problems like bushings and ball joints can cause some really insidious handling problems that are inconsistent and hard to diagnose.  This is absolutely the most important thing you can do before you spend money on mods.

Step 2:  Get some more grip and balance the car

Alright, car’s in good working order, so what do we spend money on?  The first things you need in my opinion are:

• Nonstaggered 9″ wide wheels
• 245 or 255 width, 200 treadwear tires for those wheels
• Beefy front sway bar
• Aggressive alignment
• (optional) Play with rear sway bar for balance

The nonstaggered wheels and tires will give you more grip all around, but even more grip relatively in the front since from the factory it’s staggered.  To make up for this imbalanced addition of grip and also to stiffen up the car some you want to get a beefy front sway bar otherwise the car will be super tail happy.

For the alignment, a good starting point without a camber kit in the front will be as follows:

• Front Camber:  Maximize it (will end up at 1.5-2 degrees most likely)
• Front Caster:  Make equal side to side in the 6.x or 7.x degree range
• Front Toe:  0 degrees
• Rear Camber:  2 degrees (could try 2.5 if you want a little more rear lateral grip)
• Rear Toe:  1/8″ total toe in

As for the rear sway bar, depending on your driving style you may need to leave the stock one in, disconnect the stock one, or go for a smaller one.  As a general rule, if the car is too tail happy soften the rear bar or stiffen the front.  The front bar from a NC Miata actually fits really well as a rear bar and is a nice middle ground – softer than stock but stiffer than nothing.  And it’s super cheap from salvage yards and the like, I think I paid $50 for mine.

Step 3:  Win

Bam!  Just like that, you have a really fast car.  With just this I’m confident a good driver could win STR in most regions.  Then you can start saving up for the next steps in making a nationally competitive car.

I’ll post in more detail about exactly what to do with each of these in later installments.

The post STR S2000 Guide: So which mods are most important if on a limited budget? appeared first on Caserta Racing: STR S2000 Tech.

Firstly, here’s a list of what’s allowed to be changed.  If it’s not on this list generally it has to be OEM unless it’s “for comfort and convenience”.  Of course there’s some little creative stuff you can do, but this is 99% of it.  I’ve tried to summarize any restrictions but be sure to check the SCCA rule book before spending lots of money on something.

1. Suspension
   1. Sway Bar (Front) including endlinks/mounts
   2. Sway Bar (Rear) including endlinks/mounts
   3. Shocks/Springs and/or Coilovers
   4. Pillowball (spherical bearing) top hats for your shocks
   5. Bushings (can’t be metal)
   6. Alignment
   7. One mod per corner to get more camber (for S2000s this is usually an offset upper or lower balljoint)
2. Engine
   1. Intake
   2. Header
   3. Exhaust
   4. High Flow Catalytic Converter (note test pipes are not allowed)
   5. Reflashed or piggyback engine management (has to use OEM sensors only)
   6. Engine mounts (can’t be metal)
   7. Pulleys
   8. Oil Catch Can (OCC)
3. Other Drivetrain
   1. Limited Slip Differential
   2. Differential bushings
4. Wheels and Tires
   1. Wheels can be up to 9″ width
   2. Tires that are:
      1. 140 treadwear or more (note the rules are changing to 200 or more in 2015)
      2. 255 width or smaller
      3. At least 7/32″ tread as molded from the factory (any current 140 or 200 treadwear tire meets this)
5. Brakes
   1. Pads
   2. Rotors (equal to or bigger than stock)
   3. Calipers (at least as many pistons as stock)
6. Other
   1. Racing Seats (have to be at least 25 lbs including hardware/rails)
   2. Battery
   3. Remove spare tire/trunk tools/floor mats

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