Normally a true installation lap is done when you have put new parts on the car or torn something apart and put it back together. The goal being simple enough, are all the parts working properly and harmoniously. I use installation laps during the weekend’s first practice session, a bit differently than that, and frankly differently than all of the other drivers since you can treat a Mazda GT, once it’s warm, a bit more like a daily driver than the full blown race car it is, and just hop in and go. But to pause for a second, let’s first ask the question, from a driver’s point of view just what is an installation lap?
During a proper installation lap the driver is unconcerned with his speed and is going, at best, eight tenths of his normal pace or less. It’s not a time to be learning the track or picking out marks, nor is it a time to be analyzing any off line maneuvers (to pass or avoid being passed) that you might need later. No, a proper installation lap is all about the car and what it’s doing. It’s a chance to narrow your focus to the car itself. Now a lot of the other drivers will take off to learn the track or get some seat time in right off the bat which will work out just fine. But I’ve learned over time that there are some rewards to coming up to speed slower, especially since by concentrating your entire attention on the physical aspect of the car you can spot necessary adjustments to temperatures (more or less tape) and make sure the EGT’s are dialed in as well as get yourself into a good mindset before tearing off like you’re on Mr. Toad’s Wild Ride. But maybe that’s just me so in the end do what works for you.
In fact, some of the old shoes don’t bother with the practice session at all if they are already very familiar with the track, and the new to middling guys are looking to get some seat time in full tilt boogey mode and so they take off right away and are just fine as well. The Mazda GT is solid enough for you to do that. But it is a race car not some dainty little daily driver, and in some cases it may be a race car that hasn’t been driven in a month or three. So in my mind it’s worth taking at least a chunk of the first practice session and doing an installation lap or two, even if you don’t do the whole paranoid routine that I do.
This begs the question, with no new parts on the car exactly what are the particular goals for such laps? My first goal is pretty general. How does the car sound and feel as I pull it out onto the track. You might, for example, have taken a bit of an off track excursion last time out and have thankfully forgotten all about it. If you didn’t know you bent some little thing last time out, it would be hard to tell the crew to fix it, so it’s possible it’s still there. For me, even if the car was perfect last month, I like to concentrate, at a slower speed, on how the car is currently tracking under acceleration, neutral and braking. There should be no strange thumps or bangs. No odd sounds from the drive train. No unusual vibrations. The brake rotors should feel good, even if they are slippery because they are cold. Our brake rotors and pads will seemingly last forever unless you are unlucky and pick up a stone and it cracks one, which happened to me at Thunderhill three years ago. If you push the brake pedal it shouldn’t push back. Another thing I check right at first, and several more times on the first lap, is the oil pressure gauge. Just because it hasn’t changed in the last four years doesn’t mean it’s not going to change now and the first lap out is a very good time to look at it very closely. Mine will peg after the car is started and pretty much stay pegged as long as my RPM is near race levels.
If the car feels as good as it usually does after the first lap, and the oil temperature is still at least 180 then it’s time for a straight line acceleration test. Well after the apex leading onto the longest straight, once the car is pointed fully forward, I’m going to do a little drag race. I’m taking the engine up to where I plan to shift during the race, in each gear, while keeping my eye more on the EGT’s than the track. The Exhaust Gas Temperature can vary a bit depending on conditions (temperature, humidity, barometric pressure) and it can also vary seasonally based on fuel additives and the amount of Ethanol in the fuel mix. In my car there is about a fifty-fifty chance I’ll need to go up or down one size in the carburetor jetting at the start of the weekend. Rarely, I might need to make a change during the weekend if ambient conditions change radically. The drag race run is going to give me the opportunity to take my time and examine the EGT gauges closely. I already know I’m going to brake very early, I’ve already thrown away the exit, I’m only interested in the top end of third gear not my top end speed, and I’m driving in a straight line so I have plenty of time to look. When pushing the car, later on, it’s still important to have a particular spot to check the EGT’s once per lap, but I get so busy I tend to just glance at the left side and use it as a proxy for both. This is my one chance to concentrate all of my attention on what the motor is doing without any of the distractions you have on a lap where you are fully up to speed.
If the EGT’s are a bit below 1700, for both rotors, at the top end of third gear then I don’t need a change. And don’t over think what the gauges are telling you. After you let off the gas or as you are going up through the gears the readings aren’t that important, what the crew is really interested in is the top end of third gear, just before you let off the gas or shift. Higher than 1700 and it might be worthwhile to go one step richer, below 1700 and a step leaner. It’s important to remember that these temperatures are a bit fuzzy. The car is not going to suddenly blow up at 1701, you are looking for a range and the ability to tell the crew what the car is doing; too high, too low or right on while backing it up by telling them the peak number. If you go too rich, the EGT’s may stay low but the car will be hard to drive since you are flooding it at the bottom of the power band. Too lean and the EGT’s will spike which causes excessive wear on bearings and apex seals as the motor’s internals are getting too hot and are expanding to the limit of tolerance. In the last four years I’ve never had a large valid split between the two gauges, but there is always the first time, and this is a chance to take my time and read them both carefully. The only time I had an invalid split was about three years ago, when the sensors for the right hand gauge went bad and they gave me a reading of -10 degrees right and 1690 degrees left. I’ve also been told, although it hasn’t happened to me, that if one gauge goes bad while the tachometer starts flopping around like a fish on dry land it’s a sign that one of your igniters is going and needs to be replaced when you bring the car back in. In fact, just to be paranoid I would bring the car back in that event, unless it’s during the race itself.
Once I’m happy with the motor it’s time to make sure the motor is going to stay happy with me. And that is part of my third and final test. I’m looking at how various temperatures are looking to behave over time in the current conditions. Most important is to know with certainty if the oil and water temperatures are climbing, steady or declining. You may need more tape on the radiators in a cold morning than on a hot afternoon so this can change during the day but you don’t want to, under any circumstances, run the car with the oil below 180 or above 230. That nice fifty degree gap is not all that hard to hit by putting on, or taking off, some tape on the oil or water radiator and all of the cars are going to react the same, so once anybody gets the right amount of tape, everybody will have the right amount of tape. I just like getting there first. If the oil and water temperature split, and the oil is OK but the water is too hot for example, tell the crew… but generally the water is less important than the oil unless it’s about to start boiling (above 240). During the race if you can only get yourself to look at two gauges, pick the EGT and oil temperature gauges. To get the temperatures right you need, of course, to start to bring the car up closer to a race pace since if you run it too slow the temperature readings won’t match up later on. Which is why this is my last paranoid test before switching to seat time mode. A little over nine tenths of my race pace, with shift points at my race pace, to see what happens for a lap, two at most does the trick for me. During the race itself, if it is a hot day, keep a special eye on the oil temperature if you are right in trail with somebody. If the driver ahead is stealing your air you may need to duck out of his draft on the front straight to get the temperature back down, even if it costs you speed, but thankfully that can only happen on a really hot summer day when you’ve spent a few laps right on somebody’s bumper.
The final gauge to take a look at is fuel pressure. This is one I like to check during the little drag race, to see if it drops below 3 psi, and during the longest sweeping corner, again to see how far it drops or if I’m feeling particularly paranoid that day in the longest left and right hand corners. Generally this gauge isn’t very important unless your car starts to die lean for some odd reason, in which case it’s very important to be able to tell the crew if the fuel pressure dropped at the same time you lost power. I haven’t had this gauge drop below 3 pounds in years, but I like to check it anyway during my installation laps because otherwise I wouldn’t look at it the whole weekend and I don’t want it to start feeling neglected. Besides, the more you can tell Tom and his crew how the car is behaving the smarter you’ll look. Pull in and complain about the car, without being able to tell them what all the gauges are telling you, makes it look like you aren’t paying attention.
So, do you need to do installation laps in a Mazda GT or not? I didn’t do any, none at all for the first two years I drove the car. From my own observations I’m pretty much alone in doing so now, beyond the fact that most drivers pay a bit more attention to the gauges on their early hot laps. And I didn’t even formally think through what I was doing until I decided to write this post. Tom and his crew would doubtless tell me to just shut up and drive the damn thing, that I am over thinking it since once the car is warm you can just jump in and take off like there is no tomorrow. But for some reason doing this long paranoid routine at the start of the weekend makes me more comfortable than I would be otherwise. Part of it is about getting the driver warmed up. So the answer, I guess, is do it if it makes you happy and don’t do it if it doesn’t.
During a proper installation lap the driver is unconcerned with his speed and is going, at best, eight tenths of his normal pace or less. It’s not a time to be learning the track or picking out marks, nor is it a time to be analyzing any off line maneuvers (to pass or avoid being passed) that you might need later. No, a proper installation lap is all about the car and what it’s doing. It’s a chance to narrow your focus to the car itself. Now a lot of the other drivers will take off to learn the track or get some seat time in right off the bat which will work out just fine. But I’ve learned over time that there are some rewards to coming up to speed slower, especially since by concentrating your entire attention on the physical aspect of the car you can spot necessary adjustments to temperatures (more or less tape) and make sure the EGT’s are dialed in as well as get yourself into a good mindset before tearing off like you’re on Mr. Toad’s Wild Ride. But maybe that’s just me so in the end do what works for you.
In fact, some of the old shoes don’t bother with the practice session at all if they are already very familiar with the track, and the new to middling guys are looking to get some seat time in full tilt boogey mode and so they take off right away and are just fine as well. The Mazda GT is solid enough for you to do that. But it is a race car not some dainty little daily driver, and in some cases it may be a race car that hasn’t been driven in a month or three. So in my mind it’s worth taking at least a chunk of the first practice session and doing an installation lap or two, even if you don’t do the whole paranoid routine that I do.
This begs the question, with no new parts on the car exactly what are the particular goals for such laps? My first goal is pretty general. How does the car sound and feel as I pull it out onto the track. You might, for example, have taken a bit of an off track excursion last time out and have thankfully forgotten all about it. If you didn’t know you bent some little thing last time out, it would be hard to tell the crew to fix it, so it’s possible it’s still there. For me, even if the car was perfect last month, I like to concentrate, at a slower speed, on how the car is currently tracking under acceleration, neutral and braking. There should be no strange thumps or bangs. No odd sounds from the drive train. No unusual vibrations. The brake rotors should feel good, even if they are slippery because they are cold. Our brake rotors and pads will seemingly last forever unless you are unlucky and pick up a stone and it cracks one, which happened to me at Thunderhill three years ago. If you push the brake pedal it shouldn’t push back. Another thing I check right at first, and several more times on the first lap, is the oil pressure gauge. Just because it hasn’t changed in the last four years doesn’t mean it’s not going to change now and the first lap out is a very good time to look at it very closely. Mine will peg after the car is started and pretty much stay pegged as long as my RPM is near race levels.
If the car feels as good as it usually does after the first lap, and the oil temperature is still at least 180 then it’s time for a straight line acceleration test. Well after the apex leading onto the longest straight, once the car is pointed fully forward, I’m going to do a little drag race. I’m taking the engine up to where I plan to shift during the race, in each gear, while keeping my eye more on the EGT’s than the track. The Exhaust Gas Temperature can vary a bit depending on conditions (temperature, humidity, barometric pressure) and it can also vary seasonally based on fuel additives and the amount of Ethanol in the fuel mix. In my car there is about a fifty-fifty chance I’ll need to go up or down one size in the carburetor jetting at the start of the weekend. Rarely, I might need to make a change during the weekend if ambient conditions change radically. The drag race run is going to give me the opportunity to take my time and examine the EGT gauges closely. I already know I’m going to brake very early, I’ve already thrown away the exit, I’m only interested in the top end of third gear not my top end speed, and I’m driving in a straight line so I have plenty of time to look. When pushing the car, later on, it’s still important to have a particular spot to check the EGT’s once per lap, but I get so busy I tend to just glance at the left side and use it as a proxy for both. This is my one chance to concentrate all of my attention on what the motor is doing without any of the distractions you have on a lap where you are fully up to speed.
If the EGT’s are a bit below 1700, for both rotors, at the top end of third gear then I don’t need a change. And don’t over think what the gauges are telling you. After you let off the gas or as you are going up through the gears the readings aren’t that important, what the crew is really interested in is the top end of third gear, just before you let off the gas or shift. Higher than 1700 and it might be worthwhile to go one step richer, below 1700 and a step leaner. It’s important to remember that these temperatures are a bit fuzzy. The car is not going to suddenly blow up at 1701, you are looking for a range and the ability to tell the crew what the car is doing; too high, too low or right on while backing it up by telling them the peak number. If you go too rich, the EGT’s may stay low but the car will be hard to drive since you are flooding it at the bottom of the power band. Too lean and the EGT’s will spike which causes excessive wear on bearings and apex seals as the motor’s internals are getting too hot and are expanding to the limit of tolerance. In the last four years I’ve never had a large valid split between the two gauges, but there is always the first time, and this is a chance to take my time and read them both carefully. The only time I had an invalid split was about three years ago, when the sensors for the right hand gauge went bad and they gave me a reading of -10 degrees right and 1690 degrees left. I’ve also been told, although it hasn’t happened to me, that if one gauge goes bad while the tachometer starts flopping around like a fish on dry land it’s a sign that one of your igniters is going and needs to be replaced when you bring the car back in. In fact, just to be paranoid I would bring the car back in that event, unless it’s during the race itself.
Once I’m happy with the motor it’s time to make sure the motor is going to stay happy with me. And that is part of my third and final test. I’m looking at how various temperatures are looking to behave over time in the current conditions. Most important is to know with certainty if the oil and water temperatures are climbing, steady or declining. You may need more tape on the radiators in a cold morning than on a hot afternoon so this can change during the day but you don’t want to, under any circumstances, run the car with the oil below 180 or above 230. That nice fifty degree gap is not all that hard to hit by putting on, or taking off, some tape on the oil or water radiator and all of the cars are going to react the same, so once anybody gets the right amount of tape, everybody will have the right amount of tape. I just like getting there first. If the oil and water temperature split, and the oil is OK but the water is too hot for example, tell the crew… but generally the water is less important than the oil unless it’s about to start boiling (above 240). During the race if you can only get yourself to look at two gauges, pick the EGT and oil temperature gauges. To get the temperatures right you need, of course, to start to bring the car up closer to a race pace since if you run it too slow the temperature readings won’t match up later on. Which is why this is my last paranoid test before switching to seat time mode. A little over nine tenths of my race pace, with shift points at my race pace, to see what happens for a lap, two at most does the trick for me. During the race itself, if it is a hot day, keep a special eye on the oil temperature if you are right in trail with somebody. If the driver ahead is stealing your air you may need to duck out of his draft on the front straight to get the temperature back down, even if it costs you speed, but thankfully that can only happen on a really hot summer day when you’ve spent a few laps right on somebody’s bumper.
The final gauge to take a look at is fuel pressure. This is one I like to check during the little drag race, to see if it drops below 3 psi, and during the longest sweeping corner, again to see how far it drops or if I’m feeling particularly paranoid that day in the longest left and right hand corners. Generally this gauge isn’t very important unless your car starts to die lean for some odd reason, in which case it’s very important to be able to tell the crew if the fuel pressure dropped at the same time you lost power. I haven’t had this gauge drop below 3 pounds in years, but I like to check it anyway during my installation laps because otherwise I wouldn’t look at it the whole weekend and I don’t want it to start feeling neglected. Besides, the more you can tell Tom and his crew how the car is behaving the smarter you’ll look. Pull in and complain about the car, without being able to tell them what all the gauges are telling you, makes it look like you aren’t paying attention.
So, do you need to do installation laps in a Mazda GT or not? I didn’t do any, none at all for the first two years I drove the car. From my own observations I’m pretty much alone in doing so now, beyond the fact that most drivers pay a bit more attention to the gauges on their early hot laps. And I didn’t even formally think through what I was doing until I decided to write this post. Tom and his crew would doubtless tell me to just shut up and drive the damn thing, that I am over thinking it since once the car is warm you can just jump in and take off like there is no tomorrow. But for some reason doing this long paranoid routine at the start of the weekend makes me more comfortable than I would be otherwise. Part of it is about getting the driver warmed up. So the answer, I guess, is do it if it makes you happy and don’t do it if it doesn’t.
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