ICEngineering Subjects

Sunday, October 9, 2011

BRS Recap

Heading out!

Been a couple weeks since BRS now, and since Kenneth and I decided it wasn't in our schedules to get more time for LSPR, I've taken the opportunity to see the fall colors from my mountain bike and generally get away from the garage for a week or two. And get a truck, more on that later...

Kenneth said it correctly when we didn't really believe all the NASA schedule rumors (as in, lay out the picnic blanket a couple times a day) - but sitting at what would be the start of the second special stage, with the sun going down and no lights on the car, we began to believe it. The rally was scheduled to start at 3:30, with ~30 miles of stage and transit before the first service...maybe that was part of what I was looking for. It was most important to me to run a smooth weekend, and the breaks certainly made it easy for us in the car, keeping us more rested. If I do another NASA rally I'd bring a camera to prove it.

Thanks to our small but awesome crew, Kyle Steinkamp and Matt Bushore (of Bent Mettle racing, certainly not where he likes to be instead of competing for podium as driver, but a huge asset to us that weekend), the weekend was smooth outside the car as well.

Having finished with no offs, and only 1 close call (those jumps in that video is the wildest it got, tame compared to the number of close calls at sno-drift), it's easy to say we should have driven faster. I've found that we actually did manage to destroy 2 of 3 engine mounts, but hey, the skid plate held it up in there!

So, to recap for now:
BRS Goals: All achieved
1) Find way to both rally AND eat and sleep (= have fun, all weekend)
2) Finish with no driver-error damage
3) Run the car with engine swap and custom electric

Next rally goals: As above, + actually drive fast
Also, with no MAJOR changes planned for the car, I look forward to all the finishing and sorting work which has been put off so far.

Some pictures:

Also I have a truck. It's not pretty, I've promised to keep it's name (Tank), and look forward first to wheel to wheel ice racing this winter enabled by it, not to mention actually being able to go to rally when my previous tows are themselves racing.

Thursday, October 6, 2011

STX RX-8: STX Legal Intake

SCCA's Street Touring classes were originally formed to draw in the "street tuner" crowd, so that new guys with just a bunch of bolt-ons that don't really add a whole lot of performance don't get pushed into Street Prepared where they run against a bunch of full-on race cars. Now it's just a bunch of full-on race cars with street tires.

Anyway, one of the most ubiquitous bolt-ons is the intake. It usually makes the engine a little bit noisier, the engine bay a little bit cooler-looking and on most modern engines, adds very little power. That's pretty much why I didn't put one on for my first year of running STX. Instead, I put together an exhaust that makes the car MUCH noisier, and adds a tiny bit of power. Good choice, right?

From a little bit of research, it looks like AEM's intake system nets the greatest power gains of any intake on the market. I have no idea why, because they're all basically a tube with a filter at the end. The AEM (also sold as a Mazdaspeed intake) snakes behind the front bumper support to put the filter right in the RX-8's huge grille opening. This is actually not STX legal because it requires the removal of a piece of plastic that is technically part of the cooling system, so a lot of STX RX-8 (and STR MX-5) owners have re-routed their AEM intakes to place the filter just above the bumper support, hidden by the bumper cover. This requires buying more stuff on top of the $325 purchase price of the AEM system.

Here's an example of a modified AEM intake on an MX-5

I figured I could build my own a little cheaper, so I ordered the following things:

1. 2' Mandrel Bent Aluminum 45° Bend, 3.5"
2. 2' Mandrel Bent Aluminum 90° Bend, 3.5"
3. 3.5" Silicone Hump Hose, Black
4. Silicone Reducer, 3.5" to 3.0"
5. AEM DryFlow Air Filter 21-2047DK
6. A bunch of hose clamps

I actually ordered more stuff but ended up not needing it.

First, I pulled the MAF off of the existing intake and measured it so I could reproduce its mount in aluminum.

Then, I realized that people just sell these things for $13!

I stripped the old intake off the car, and started shoving stuff into place:

Step 1: Remove everything. And yes, I know it's really dirty in there.

Step 2: Jam filter between core support and bumper beam

And Step 3: Connect the dots. That was the time-consuming part. I actually got away with just cutting up the 45 degree bent tube into two pieces and welding it back together in a different orientation.

Step 4: Stick these things togetherI'm still figuring out this aluminum welding thing

Step 5: Bolt it all together and now I have a sweet looking intake!

It's sweet looking if you ignore that one rusty hose clamp

I weighed all the crap I took off at 12.124 lbs (it was a needlessly precise scale), and all the new stuff weighed in at 4.848 lbs, for a total weight savings of about 7.25 lbs. I can't tell a difference in power, and I really don't notice any difference in noise due to my ridiculously loud exhaust. All in all, I'm not sure that it was worth the $150, but it looks pretty nice and it was fun to build.

Next installment will be the battery. You can see in the photos that I already got a little one, but it's mounted really poorly. That should be taken care of within the next week.

STX RX-8: Introduction

This is my 2005 Mazda RX-8:

I bought it new in July of 2005 and since then, it's been through a lot:

And by that, I mean a lot of dirt

I started autocrossing the car back in 2008 with the Detroit Region of the SCCA. I started out driving it completely stock in our local Street Tire B Stock class. In 2009, I graduated to R compound tires to run in the nationally recognized B Stock class. I also began to travel a little bit more for events, hitting the large sites in Peru, Indiana, Toledo, Ohio and Oscoda, Michigan.

In 2010, I decided that I didn't want to have to buy more R compounds (they're super expensive and last less than 100 runs) and I wanted to tinker with stuff, so I made the leap to the Street Touring eXtreme (STX) class. I used the Koni Sport dampers that I had been running in Stock, added some coilover sleeves, machined some spring perch adapters to take 2.5" ID race springs, bought some wheels and tires, welded together a catted midpipe, and I was in STX for only about $1500.

Pictured: Really cheap suspension

The car handled pretty well from the get-go, netting me better indexed results than I had ever achieved in Stock class. Of course much of this could be attributed to experience, but it was also more fun than ever without the massive body roll brought on by the soft-spring/high-grip setup Stock setup. With just some alignment tweaking and driver adjustment, the car got better and better through the year. In fact, my co-driver at the Toledo Pro Solo took second place just behind the eventual STX national champion, while I coned away fourth place and ended up way back in tenth.

In 2011, I netted myself a co-drive in a friend's STU Mitsubishi Evolution IX (to continue my trend of jumping classes every year). The car is extremely well-built, featuring AST dampers and TONS of horsepower.

It's real pretty too

I ended up making my first trip to Solo Nationals in that car and having terrible results on one day and pretty good results the next.

For now, the plan is to go back to Nationals, with pretty good odds of driving my RX-8. This means that it needs to be close to the level of prep that the Evo is at so that it actually has some shot at being competitive. Unfortunately, I'm super cheap so I try to do everything the hard way rather than spending a few extra bucks to get bits and pieces that already exist. But, that affords me the opportunity to make stuff and get some fabrication experience. So, I'll be documenting some of the stuff I make/buy/modify for my RX-8 here on the blog.

Things on the list:
1. Intake
2. Little battery with custom billet tray/tie-down
3. New rear dampers
4. Custom full 3" exhaust, possibly including header
5. Cobb AccessPort and tune (well, this one is just paying somebody else)

Let's see how much of this actually gets done!