Track Day Experience

As much as I love working on the car, there is nothing quite like taking it out on the track and pushing it to the limit. It’s a good measurement of how the car performs, and it’s an opportunity to become a better driver as well. Since I’m not a professional driver, and my car is not prepared for sanctioned track events (no cage, harnesses, etc.) the next closest thing for me is an HPDE (high performance driver education). It’s essentially a track day with a catch – you get an instructor that works with you to improve your driving and you spend about an hour and a half in a class room talking about general driving techniques and the track itself. You typically get 3 sessions at about 20-30 minutes each session to go out on the track and run your car at full speed. You can pass other people with some restrictions based on your skill group. So it’s not truly racing, but it kind of is. If you’re faster than the other person then you will pass them, but typically in a controlled manner.

This is my third year doing HPDE events, and I really like the Putnam Park road course outside of Indianapolis. It has grass runoff around the entire track except for the pit entrance area, where there is an armco. This means that if you screw up somewhere on the track, chances are you’ll just spin out in the grass and not do any terrible damage to your car. This past weekend I had a spin and all that happened was a dent in my splitter, although I did experience some significant other damage that was not the result of the spin (more about that in another post). However, this is a good time to mention that if you aren’t comfortable with ruining your car then don’t take a chance on a track day like this!

Here are some beginner tips for HPDE:

  • Bring some tools to the track, especially a torque wrench for your wheels and a tire pressure gauge to bleed off excess psi
  • Make sure you change your brake fluid and bleed your brakes before a track day.
  • Good tires are a must. I really love the Nitto NT01, but as long as you don’t go on bald tires you should be relatively ok as a first timer.
  • Bring lots of water/gatoraid and stay hydrated. It’s exhausting racing at high speeds even for 20 minutes at a time. When you are exhausted and dehydrated you make mistakes.
  • Make sure you have adequate brake pads and rotors. You don’t want your brakes failing at the end of a straightaway doing 130mph or more.
  • Don’t drive with aggression or angry. Everybody is there to have fun and if you aren’t the fastest then learn from it and get better without being a jerk
  • Record your driving if you can and watch the video later to understand how to improve your lines. (This really helped me)
  • Try to ride with an instructor to see how they drive and learn from it.

There are a lot of great tips typically provided with the information packet on a per school basis, so make sure you read those tips as well as any specific information you can find out about the track ahead of time.

Here are some specific tips for Putnam Park road course (please keep in mind I’m no expert!):

  • You can carry a lot more speed through turn 1 than you may initially think. I can brake at the 300, 200, or 100 just fine. Tap the brakes and get off of them, don’t ride the brakes or you will overheat them quicker. I think a good average speed through turn 1 is 90mph for reference. So I brake from 130mph to 90mph very quickly and then take it.
  • I like to downshift from 4th to 3rd at turn 2 when I brake. It feels better than downshifting from 4 to 3 at the brake point on turn 1.
  • I hit turn 4 as a late apex.
  • I turn in late on turn 5 and try to make 5 through 7 feel like a straight line
  • I brake and downshift to 2nd gear and turn in early on turn 7. This is the slowest turn on the track. I use a little controlled oversteer to push me through this corner quickly.
  • I turn in early on turn 8 and ride the inside line up.  Lots of fun!
  • Hit the curbing on 9 & 10 to set up for a good launch on the straight. Don’t lift here or you’ll potentially loose control and hit the barricade. Feather the throttle until you’re ready to go flat out.

Lots of good information on Putnam Park can be found here: http://creativecrawler.com/2010/02/putnam-park-track-day-dissection/

Here is a video of my second heat. The battery died before I finished. The first lap is to warm up the tires and is at about 50% speed. The second lap had a caution flag as a car went off, but then we get rolling after that.

Brake Master Cylinder Heat Shield

So you upgraded your calipers, master cylinder, lines, and pads expecting your car to be able to handle the increased power. Driving around town they feel great and you can really feel the improvements. When you hit the track, something else happens. You’re heading down the straight over 130mph and when you go to hit the brakes into turn one your pedal just falls to the floor and your speed is not decreasing rapidly enough…

This is not the situation you want to find yourself in, and it’s not the appropriate time to be going over your checklist – did I bleed the brakes properly, are my brakes overheating, did a hose or line come loose?

If you’re like me and went with a top mounted turbo but you did nothing to shield the heat of that turbo from your brake master cylinder then you should probably read on before you find yourself in a situation where you may end up off track or worse, in a wall.

Very simply, the exhaust housing of the turbo gets really hot under normal use and extremely hot when doing lap after lap in the middle of the summer on a road course. If you don’t have a turbo blanket or ceramic coating on the housing then all of that heat is hanging out in the engine bay and saturating surrounding components. The closest thing in an S14 setup is going to be your brake master cylinder.  You’re basically boiling your brake fluid causing it to compress substantially before actually providing the stopping power to your brakes.

A heat shield is a relatively cheap solution that only takes a few minutes to install. It’s something you can buy online from companies like Circuit Sports or Megan Racing, or you can fabricate your own. I’ve seen some elaborate custom setups using gold plated tape to act as an improved heat reflector. How far you want to take this depends on your needs. Consider this a step in the right direction, but in extreme situations it may not be the final solution. I will be able to report more after my first track day of the season.

The concept here is the heat shield is a metal partition that separates the BMC from the turbo and downpipe. The heat is reflected off of the metal and does not get absorbed as easily into the BMC. The one I purchased was designed for an S13 but is easily adjusted to work with an S14. It simply bolts on to one of the BMC bolts, and the other one went where I believe my original power steering pump would have mounted. Two of three holes matched up on the S14 without any adjustments required. However, I did bend and hammer one of my corners down to get it off of and away from my downpipe. I also bent one of the top edges outward a bit to give extra clearance from my brake lines. I didn’t want the metal rubbing or touching for safety reasons and to allow the shield to do it’s job properly.

This installation took me less than 15 minutes, including my adjustments and I highly recommend it for those of you who do any serious driving in your modified S14.

The turbo is too close to the unprotected brake master cylinder
The turbo is too close to the unprotected brake master cylinder
An inexpensive heat shield will help protect the BMC
An inexpensive heat shield will help protect the BMC
A test fitting shows the heat shield will bolt up fine, but it touches the downpipe
A test fitting shows the heat shield will bolt up fine, but it touches the downpipe
closeup of the heat shield touching the downpipe
closeup of the heat shield touching the downpipe
I marked the shield and bent and hammered it to avoid touching the downpipe
I marked the shield and bent and hammered it to avoid touching the downpipe
I pulled the shield outward at the top, away from the brake lines
I pulled the shield outward at the top, away from the brake lines

Understanding Torque Specs

It’s important to understand that when working with moving parts, the amount of force in which you tighten a screw or bolt is important. The parts you are attaching are designed by an engineer to stay together when tightened to a specific measurement, commonly referred to in the US as foot pounds of torque (ft-lb). These readings can also be performed in Newton meters (n-m) and kilograms per meters (kg-m). If you open a factory service manual (FSM) you will see an exploded diagram of various parts of an engine, and where the bolts are referenced you will typically see a small range of numbers. These numbers indicate the tolerance range that you should follow when tightening you bolt.

The easiest way to ensure a proper torque reading is with a torque wrench. There are a few different types, but I like the break-away style. They look like socket wrenches, but the handle will turn to set the preferred torque and then when you exceed that limit the head will click, indicating you have reached the limit and to stop tightening.

If you do not follow proper torque specifications, there is a good chance your engine, suspension, wheels, or other moving parts of your car can come apart causing serious damage or injury. So when working with an engine, don’t tighten it by feel or until you can’t turn it any more. Over-tightening can be just as bad as under-tightening.  Follow the specs!

I am attaching a PDF showing some diagrams from the RB25DET head for your reference.

RB25DET Head

Gauge Cluster Light Change

So I decided to change out my gauge cluster lights to some super bright white LED bulbs. It looked a bit sharper, that’s for sure. But then I decided that the light was a little too crisp so I instead went for the amber Sylvania bulbs (similar to what you would use in your side markers). I thought they looked neat but my wife thought they were generic looking. I’ll probably go back to the factory bulbs as a result.

The upgrade is super simple and only takes about 10 minutes. You simply unscrew your top cover of your steering wheel, then you unscrew two screws from the top of your dash hood that covers the cluster and pop off that piece carefully (where your light dimmer and cruise control switches are located). Undo the plug on your cruise control and swing it to the side. The dimmer needs to be plugged in to test your bulbs before re-assembly so you can keep that plugged in if you want.

Now you see 3 screws that hold your cluster in place (one on top and one on each lower side). Remove the cluster (don’t bother disconnecting the wiring). You can now swap out the three wedge style bulbs by half-turning them to unlock and voila…. you have new lights.

There are plenty of good write-ups on this.

IMG_3163 IMG_3164 IMG_3165 IMG_3166 IMG_3169 IMG_3170 IMG_3171

gauge cluster
gauge cluster

Seasonal Change

When the season changes I find myself not driving the 240sx quite as frequently. Tonight I was adjusting my ride height (and somehow my driver side rear was quite a bit lower than the passenger side). When I was finished I re-torqued all of my wheels (a good practice when the weather changes) and checked my tire pressures. The pressure on my Nitto NT01 had dropped down to 20psi. Don’t just check these things on track days. You should be checking them fairly regularly, and at the very least check everything over when the weather starts to change.

The weather had changed enough around here that my IC piping actually got a bit loose and I blew a coupler off when driving on the highway this week. So it’s probably a good idea to check anything that can contract or expand with weather change. If you plan on parking your car over winter and not driving it, you may consider a fuel stabilizer to prevent start-up issues in the Spring.

Remember, if you’re like me and you have performance or track tires that are not all season, be careful driving them when the temperature is near freezing. They will not get enough heat in them to grip the road and you could find your project car in a ditch quicker than you know it. Be safe!

C-West Aero Kit

Last year I bought a C-West body kit for my S14. It arrived in two shipments due to some delays with Japan and the Tsunami that hit. My plan was originally to install it over the winter but we ended up moving. And then it was Spring and I didn’t want the downtime that may come from it since I had to do some modifications to make the kit fit.

C-West Aero Kit S14 240sx

Well, after several delays I finally got the kit installed. Installing a body kit can be relatively easy if you’ve done it before, but if it’s your first time it can be quite confusing. Let me explain a few of the steps that made my life a little easier the second time around.

First, make sure you test fit the kit before you paint it. You will most likely need to cut and sand the kit to get it to line up properly. The cheaper body kits will not match up very well at all without some work. They also don’t typically come with the holes drilled, so you’ll want to do your best to match those up with the OEM holes (and you’ll probably need to drill a few of your own as well). Go ahead and mount your lights in the front bumper to make sure they fit (they usually don’t). When you’re doing your front bumper, you may actually have to notch your bumper support depending on whether it’s USDM or JDM. The JDM vehicles don’t require the front crash bumper so you may run into fitment problems here. I used a circular saw to notch my bumper. It’s easier if you go ahead and remove your front headlights while mounting the bumper. You may also want to jack up one side at a time and remove your wheels for easy access to mount the side skirts. The C-West kit itself would have fit perfectly if I didn’t have a FMIC or USDM bumper support. The bolt holes were pre-drilled and everything lined up nearly perfect.
Once you have test fit everything and it matches up pretty good you’ll want to paint the kit. Make sure you sand and fill as needed, because most kits will have pin holes or seams from the molds used to create them. After the kit is painted you just reinstall it on the car very carefully. I like using a mixture of bolts and OEM style push plugs. The bolts are mounted in discrete locations but help keep it firmly attached, and the push pins are for more obvious locations that give it more of an OEM look. On the S14 you have some holes for mud flaps in the rear wheel well and you can use the fender cover screws in the front wheel well, but the side skirts will need two holes drilled in the rear wheel well closest to the front of the car. You’ll need to remove the wheel to do this of course. It’s also a good idea to use double sided tape along seams, but make sure that you position it so that it doesn’t show through when looking at the kit from above. You’ll want it off the edge just a bit.

When you’re all done and lowering your floor jacks, make sure you don’t crack your side skirts. If it’s going to hit the jack, just slide a piece of wood under your tire and then lower the car down.

There aren’t many tips on the web about installing custom body kits, but I found that it’s relatively easy once you’ve taken the time to learn how to do it yourself.

New Fuel Pump Install

Today I installed a new Walbro 400lph fuel pump, replacing my Walbro 255lph fuel pump.

Walbro 255 vs. 400 fuel pumps

This is a 30 minute upgrade if you know what you’re doing. It can take longer if you’re unfamiliar with the S14 fuel system. There are a few things to point out about my Walbro 400 fuel pump that cause me a slight delay:

  1. The plugs it came with do not match up to anything. It’s almost like I had a kit for another vehicle. Just clip the plug and crimp or solder the wires to the connector on the S14.
  2. The rubber isolator does not match up with the Walbro 400 bottom. You have to kind of cram it into place with the bracket. The 255lph fit like a glove, so this is unfortunate that the over-sized base made the isolator a funky fit.
  3. The S14 fuel sock/filter is a tight fit on the 400 but fit perfectly on the 255. You need to use a hammer and a small screwdriver and lightly tap it into place.
  4. Pay attention to the + and – symbols on the fuel pump. My 255 was wired backwards. The black was + and the – was red wire. I followed the wire colors instead of the terminal symbols and wired it backwards the first time, which wasted a lot of my time.

New Walbro 400lph Fuel Pump

Walbro 400lph Fuel Pump

At our last dyno tuning session, I maxed out the Walbro 255lph fuel pump around 25psi. The car had more to give, but the pump was the limitation. Enter the Walbro 400lph pump! This pump should give me the fuel pressure I need at higher boost levels without requiring a secondary, in-line fuel pump. The installation seems pretty straight forward, especially since I already have a Walbro pump installed. I’m hoping that the wires and plugs match up, meaning that this can be a 10 minute swap. Here is a good writeup on installing the Walbro in an S14. This is a nice video for installing the pump in a 240sx as well (it’s part 1 of 2).

New Nitto NT01 Tires

New Nitto NT01 Tires
New set of Nitto NT01 tires for the track season

My new tires finally arrived! I ordered a set of Nitto NT01 tires for the 240sx in hopes that this will be a step up from the Dunlop Star Spec tires for my track days this summer. the Dunlop’s were great for Auto-X, but they fell short on the track in my opinion. I’m not quite ready for racing compounds, but I feel that this is a step in that direction. Perhaps next year I’ll get a second set of wheels to swap at the track like most of the other guys do?

I’m going to remove my wheels and have these mounted tomorrow. I don’t want anybody using an impact wrench to tighten my lugs! =)

Next Project is A/C

For my next project I will be reinstalling A/C in the car. After the RB20DET swap went awry, I disconnected the entire A/C and sold off the motor set. I sourced an RB25DET compressor and mounting bracket from RAW Brokerage. My lines are already modified to work with an RB20DET compressor, but they are slightly different (appear to be backwards). So I’m going mock up the new lines with the help of a local shop once the compressor and condenser are in place. I’m shooting for a custom discrete A/C line look. The engine bay is crowded enough with my ABS module.

I’ll be sure to snap some photos and explain the basics. It seems to be a fairly straight forward process if you have somebody that can modify the lines. We’ll see…..