I rode in a friend’s Ferrari (1978 308) recently and while I love how it sounds… I often can not get enough of the turbocharged sound. So if you love the sound of turbochargers doing work here you go:
Link for you RSS peeps.
It may be an older video of ours, but I love it and cannot get enough.
Update: Apparently I decided to post this exactly two years after uploading it to YouTube. Odd.
I finally got the time to watch EuroSport’s coverage of the WRC Italy race, well the review of it at least. As Charles pointed out the other day, Rally isn’t the most spectator friendly sport, since the race occurs over so much distance, and takes up a lot of time due to everyone racing against the clock instead of next to each other like most other motor sports. As a result, most people only have the time to watch the highlights of every race. Now I need to watch the races that were in Greece and Turkey.
A funny thing about rally races is how much effort it takes to stay in the lead. After the first day, the two Subaru cars were doing quite well, but by the end of the second day, Solberg had some unknown issues, like he often does, and Atkinson just wasn’t keeping up with the pace, and just like that, Subaru is basically out of the running. Atkinson ended up in 6th overall.
Loeb managed to win the event, as he has been doing quite often lately. The combination of his driving skills, the partnership between him and his co-driver, and the reliability of the Citroën car seems to work out to get him on the podium pretty consistently.
Also putting in a solid effort are Hirvonen and Latava. Ford has been dominating the top 10 in the recent WRC events with sheer numbers, getting four of the top 10 places. It is quite amazing how many Ford teams are competing this year. I’m not going to complain though, since this much involvement from an American car company can only be a good thing for bringing the sport here to the USA.
So if you haven’t watched the Italian WRC yet, I recommend doing so, it was a pretty exciting race in a fairly tough course. A few large jumps and rather bumpy terrain puts a lot of strain on the suspension, and there are the typical crashes and component failure that goes with the car abuse that is known as rally racing. Definitely good times to be had by all!
“You’re older than you’ve ever been and now you’re even older, and now you’re even older, and now you’re even older…”. Today is my birthday. I am older now and closer to getting a rally car. Time to go celebrate being older.
It seems to me that when people want to upgrade their car to give better performance, they focus a lot on creating more power. Sometimes there will be brake upgrade or suspension modifications, but rarely do I hear or read people talk about the best performing tires for their car, and I really don’t know why.
When it comes to making a car move somewhere, accelerate, decelerate, turn, slide, whatever it is you make your car do, the tires are what provide the traction to do so. Perhaps one problem is that there are performance tires for almost every application. High performance dry tires, mud tires, snow tires, rain tires, hell, even ice tires. There are so many choices to choose from, It makes me wonder if many just pick out any old all season tire for the ease of use and practicality. Even then, within a segment, tires are all different. Some are softer, providing more grip and faster wear, the tread design is different, the sidewall thickness is different, even the contact patch width varies between tires of the same ‘width’.
But do not let this faze you. Tires are, in my opinion, the most important piece of equipment on the car to understand. Now I’m not asking that everyone knows which compound and tread combination will give the best traction on a dry surface at a 10º slip angle, but please, just use common sense and get a nice set of tires.
Why do I bring this up? Well, I finally got the opportunity to take my winter tires off my car the other weekend and put the all seasons that were on the car when I bought it back on. The difference in handling, and general amount of traction available is incredible. The snow tires I had on were Dunlop SP Winter Sport 3D’s, and they should really be called all season tires with a tread that makes it good in snow. In comparison, the actual all seasons have a much less aggressive tread. As a result, the predictability in hard cornering is much better, and all around traction when the roads are dry is far superior to the snow tires. But then when the roads get wet, the snow tires deal with the water much better, no doubt thanks to the deeper tread.
So yeah, next time you start budgeting out parts for your car, be sure to include a nice set of tires that work well in your application. For Charles and I, we’ll probably aim for a set of all seasons with good mud and dirt capabilities for the rally car.
HowStuffWorks, that famous website, has a blog and one of their entries is on Offensive Driving. Marshall Brain, the founder of HowStuffWorks used our “How To J-Turn” video as proof that YouTube can help you with your offensive driving.
Anyway the article is here. It is neat to see that people actually watch our videos and occasionally read our website.
ECUs are black boxes that make your fuel injected engine run. They are commonly microcontrollers that take some inputs in, compare those to a table and spit out an output or two.
What are those inputs? Basic ECUs look at only a couple things, including: Air available (MAF/MAP) and Engine RPM. The Air Available is related to the throttle position. The Engine RPM equates to how long the valves are open for and combined with the air available the computer can figure out how much air is entering the cylinder. With that key piece of information the ECU can then figure out its output.
What is the output? We are still considering the basic ECU here. It has one output, and that is the amount of fuel it should spit into the cylinder/manifold. Really, it is even simpler than that. The output is just how long the fuel injector fires for.
But of course we can make the ECU do way more than manage a single fuel injector. Now they commonly control 4+ fuel injectors and at least the spark plugs. We could also slap on a boost control unit for any turbocharger that is in the car. While we are at it let us add variable valve timing to the mix and control that with the ECU. We could even make it more accurate by adding a bunch of inputs…like:
All of this in a pursuit to more accurately control the amount of fuel we inject into each cylinder at a given time. Some of the inputs determine how much air is available, while others are guessing at how much power the driver really wants. And one important input is watching to see how wrong the ECU’s previous decision was, so it can self correct (hint: we breath what it looks for).
However, what I find funny is that all the ECUs I have ever seen achieve this by looking up fuel injector times in a table. What takes a human mind ages to do succesfully a computer can do in practically an instant. But with every input we add a dimension to the tables. This makes me wonder what the future of the ECU is. Will we start making simple mathematical formulas to take these inputs and quickly produce an output? Maybe we will augment the result from the table with some formulas, but I don’t know yet.
What I do know is that, as computers get faster and more robust, so do automotive microcontrollers. This will allow us to continually add to the giant black box we call the Engine Control Unit. The more we add to it, the better off cars will be. We can give even more control to the driver (not likely) and allow them to choose economy or performance, or maybe even torque curves and rpm limits (Variable Valve Timing).
Hopefully I was able to get you somewhat interested in ECUs. Maybe I’ll be able to start a series on ECUs much like Mark’s Turbocharger series. Perhaps even one day, work on my own custom ECU for a rally car.
Rally, as it commonly does, flipped the results around this weekend at STPR in Pennsylvania. With much of the common podium finishers not finishing this rally it left some drivers, who are often overlooked, the opportunity to place on the podium.
Antoine L’Estage and Nathalie Richard finished first in their Hyundai Tiburon. They were followed closely (only 17 seconds overall) by Tanner Foust and Christine Beavis in a Subaru WRX STI. Finishing up the podium in third was Matthew Johnson and Jeremy Wimpey in a Subaru WRX STI.
I’m a large fan of Andrew Comrie-Picard (ACP for short) and unfortunately he DNFed this weekend. Fortunately for him he is still leading Rally America in points (59), which means he should show up to the X-Games this summer. If you like videos and are interested in Rally, ACP maintains a neat YouTube channel as ACPRally.
Summertime is here in Arlington, Virginia. The days are longer now, the nights are warmer and there is beautiful weather to drive in.
Hopefully you all are enjoying stellar driving weather (which is pretty much anything to me). Let us look forward to a wonderful summer.
Mark just moved to a new apartment so he won’t be writing again until he has his internet up. There is a rumor kicking around that he is working on the technical details of his next Turbocharger article. If you haven’t already read the first two articles: Part One and Two are here on TwoGuysRally.
I am fully distracted by TwoGuysRally, Family&Friends and a small company I am working on. I am trying to figure out how to make this site easier to navigate for you. I feel like my past articles are ignored by new readers (Google Analytics feels that way too).
If you are new to the site check out some previously popular articles including: How To J-Turn and its Video. How To Double Clutch and its Video.
Otherwise, does anyone have any suggestions as to how the site should look and feel and navigate?
Some money and time issues are preventing me from going to STPR. It is unfortunate, but I think I’ll be able to provide some entertaining content regardless. A bunch of guys from DirtyImpreza.com are going and unfortunately I won’t be able to meet them.
I plan on making up for this by attending New England Forest Rally in Maine.
In the mean time, I think I may have found a car Mark and I could use to rally. Let’s hope!
When there are such awesome things like Rally in the world, why is NASCAR the dominant motorsport in the United States? That is a question I’ve been asking myself, along with “What made NASCAR become so popular in the first place?”.
I’ve found a few points that make it so popular:
It is easy to spectate. Hillclimbs and Rally Races are hard to spectate. You have to go out to the middle of nowhere and bring a seat and your own beverages. NASCAR lets you come to a stadium where you can park, buy tickets and sit in a stadium style seat where you can easily order beverages or pick them up.
Many times people will go to a NASCAR race to support their favorite driver (and have a nice day out). They get to watch their favorite driver go around every corner and crash if that happens. Stage races only allow a spectator at glimpses of the driver throughout the stages. So spectators may be disappointed with the amount of time they see their favorite driver(s).
Alcohol. So many of the NASCAR sponsors are alcohol related. Even a whole series was named after a shit beer. Alcohol is the biggest reason I think NASCAR is watched. It is an excuse to sit around, drink beer, eat some food and hang out with some buddies. This makes me wonder why many Rally races in the US remain alcohol free. I get the safety part of it, but at least push for alcohol in some areas if it will make the sport more popular. The rallies in Europe have some trouble with alcohol, but then again, look at how popular they are.
Marketing. NASCAR was almost tailor built for advertising and sponsorships. This resulted in a positive feedback loop between the sponsors and NASCAR. Promote NASCAR and your stuff gets promoted too. So the marketing teams of many many companies worked with NASCAR to help promote NASCAR and themselves. Really, it is an excellent business strategy where if NASCAR got huge, any sponsor would also get a ton more coverage. I am quite sure this is what Rally America is hoping to do with Rally. It has achieved a ton of coverage thanks to the X-Games, and Rally America is hugely responsible for that.
I’ve got some more ideas kicking around in my head, but most of them are infants. I’ll post some more about why NASCAR is so popular later.
But now I would like to hear what you think about what makes NASCAR the dominant race league in the US.
I have been troubleshooting my car for the last week or so, as I had talked about previously. I had some time recently to take a closer look at the engine, thanks to school being done for the quarter and getting a week break before I started work.
I started off by taking a closer look at the list of things I had suspected to be the problem:
In the previous post, I ruled out number four by detaching the exhaust after the turbine outlet temporarily.
Since then, I have checked for vacuum leaks and made sure the TCV functions properly by checking manifold pressure throughout the RPM range. The pressure gauge indicated good idle vacuum at around 19 mmHg, which is approximately where it should be. Though this basically rules out vacuum leaks, a cursory glance at the vacuum lines showed that if any are leaking, the cracks are small enough to not be seen at idle.
The turbo was generating around 10 psig of boost at wide open throttle (WOT) by 2300 rpm, and held up until around 5500rpm, when I shifted into third gear. Because of this behavior, I believe that the TCV is operating properly in that the wastegate is held to a position that will allow just enough air around the turbine wheel to generate the 10 psig of pressure the ECU calls for.
This leaves the CBV or something else that I didn’t immediately think of. Without explaining my suspicions to him, I took my dad out for a drive to see if he heard anything strange, as he has better hearing than I do. After after accelerating hard in second gear from around 20 to 45mph, he pointed out a wooshing noise that started soon after I got on the gas. I listened more carefully for the noise he was describing, and it sounded exactly like the CBV on Charles’ WRX after we removed the Snorkus.
So from this, I am certain the CBV diaphragm is leaking a lot, which means that a lot of compressed air is going back to the compressor inlet. The compressor must then spin faster to make the same amount of boost at a higher mass flow rate. This means two things, both pretty bad. First is an obvious one; The faster the turbine/compressor wheels spin, the more wear there is on the turbo overall. The second is not quite as obvious. Since the turbo is now doing more work to move that extra air through the CBV, the wastegate is not open quite as far as before, which results in more backpressure on the engine. This reduces power and increases exhaust gas temperatures a bunch, especially in the top end when the turbo has to do the most work.
What’s next? I need to get ahold of a CBV diaphragm for a Mitsubishi TD04HL-16T turbo to replace the current one, and see what happens from there. Just for the sake of being thorough, I should replace the vacuum lines too. Age and heat does wonders for rubber, and I’m sure that even if the idle vacuum is good, there are tiny leaks here and there, which bothers me to think about. As with all other works in progress, I’ll update you guys on anything that happens.
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