Car prep and techniques for drag racing

[gerryvz]

I have campaigned my various cars (6.3, 6.9, 560SEC, E500) for drag racing for the past 5 years or so, every summer, at our local track Portland International Raceway.

I would be happy to provide like-minded individuals here with my secrets, tips, tricks, techniques at car prep and driving/racing, if there is sufficient interest. WIth the 6.3, I was able to shave nearly a full second off my times with constant refinement and honing of technique, and proper prep.

I'd also be happy to talk about good equipment to have on hand to assist the Merc owner who likes to get his/her car out and stretch its legs once in a while at the strip.

Contrary to the perceptions of many, drag racing is a very very fun sport and a great activity to do on a Friday or Saturday night, or whenever your local track opens up to the public. I know that some club members and owners feel it is an activity that is "umbecoming" of an MB, but this is simply not the case.

The fact of the matter is, that drag racing is simply one heck of a lot of fun, and if you haven't done it, you shouldn't knock it !!

Others may feel that drag racing puts unnecessary stress and strain on the cars and various components. I am also happy to say that after hundreds of runs in four of my past and present cars, I have yet to experience a single component failure due to racing either on or off the strip. THe fact that MB makes AMG models (as well as other high-performance models in past years) says very much that MB cares about performance, and for the US market this definitely includes acceleration over the quarter mile. THe car magazines test 1/4 mile acceleration and 0-60 times for all of their cars' road tests, so this is an accepted measure of a car's overall performance and a basic and objective measure that can be used to compare it to other models and marques.

Most of my drag racing has been with V-8 powered and relatively stock MB sedans, simply because until recent years the most powerful and high-performance MBs have been "stealth" sedans such as the 6.3, 6.9, 190 2.3/2.5-16, and 500E.

If anyone has any questions about how drag racing or bracket racing works, I'd also be happy to answer them in this thread. Hopefully this can become a definitive thread on all things drag racing for MBCA members and prospective members.

Cheers,
Gerry

[JimVillers]

Gerry ..... You remind me of my youth when drag racing was what we did both on the street and on the strip. A long time ago but lots of fun. I had a 1951 Chevy with a Cadillac engine and a Packard transmission with a big tower. I haven't been to a strip in years and I believe that my nearest strip is about a hundred miles.

On the other hand, autocross has much of the same characteristics. Guys that like to use their cars to the limit.

All performance events seem to draw a different segment of the car hobby. It is the doing aspect of cars and most participants also enjoying working on their own cars and modifying them to perform better.

Gerry, I would be interested in you preparation routine. A full second in drag racing is HUGE.
GE.

[Maxbumpo]

Gerry,

Please do share! I'm not planning to drag race but am going to autocross.

[gerryvz]

DRAG STRIP TIPS
By Gerry Van Zandt
August, 2004

When you are going to the drag strip, the objective is to traverse the 1/4 (or 1/8) mile distance in the shortest possible time. Typical "open to the public" drag racing nights utilize an approach where cars are paired up by a stager as they come up to the front of the staging lanes, and then proceed to the burnout box and on to the starting line.

Other approaches, used primarily in competitive situations (where points are kept on a regional or national basis), would be an bracket elimination approach, or a scoring approach whereby the owner puts his best guess of the car's actual time on the window, and the car's performance in relation to this estimated time is then responsible for the ultimate score.

But for your typical "run what you brung" drag nights, the pairing-up approach and a straight start-line to finish-line time approach is the dominant scoring system for amateurs.

CHRISTMAS TIME

The starting controls of the drag race are the "Christmas Tree" which is a vertically stacked series of lights placed in the middle and ahead of the two drivers lined up at the starting line. There are two sides to the Christmas tree corresponding to each lane. Each side has its own set of staging lights, countdown lights, and a "red light". The purposes of these lights are explained next.

Two yellow staging lights ensure the proper placement of your car at the starting line. The first yellow light means you're almost in position; the second light means that your car is in position to start. Below the yellow lights are three green lights. These lights begin at the top of the stack of three lamps, and come on progressively about a 1/2 second apart. The race is on when the third (bottom) green lamp lights up.

In the event of a false (early) start, whereby a car jumps the gun, a red light below the bottom green lamp, lights up to indicate this. The race continues to proceed, but technically the driver is disqualified and the other driver wins no matter what his time. However, you still get a timeslip and can see how your car performed.

WARMUPS AND BURNOUTS

The intent of burnouts is to heat up the tires to make the rubber softer and stickier, and to get any debris/rocks/crap off of the tires to provide the smoothest and most contact patch to the race track. Many people do burnouts just because they think it's the thing to do, to impress others, or just because they can and it's a legal place to do this. Unlike Bill Clinton, many gearheads find that inhaling tire smoke and muscle-car exhaust is far preferable to marijuana and tobacco smoke. Also we all know how much the chicks absolutely "dig" having to inhale tire smoke. And it certainly helps the plants grow faster too, and is an act that is heartily endorsed by Greenpeace and the Sierra Club.

Burnouts are performed in the burnout box, which is maintained by track workers constantly with brooms and a bucket of water. The workers spread a little bit of water to wet down the burnout area between burnouts, and sweep the water to spread it while removing any large rubber or debris chunks in the area. The pavement in the burnout box area is encrusted with burned up rubber adhering to it.

Lots of theories abound here. Much depends on your tires. If you are using drag racing tires (slicks or sticky shaved-tread drag tires), these tires are designed to be heated up to make them stickier, and this protocol should be observed. If you are using street tires (low-profile performance radials) then burnouts are of little to no use, and really just wear down the tread quickly with little if any positive effect at start on the drag strip.

I have found that a "dual burnout" technique works best. This means that I do a first, long, chick-impressing burnout in the burnout box. Then I pull forward 10-15 feet, and do another, second burnout on dry pavement to "finish" the wet burnout from the burnout box and dry off the tires. Then I pull forward to the final staging and starting line.

My bottom line is that if you are running street tires, don't do much of any burnout at all. It's not needed unless you want to hit on that hot 18-year-old blond standing near the starting line after the race. If you have drag radials or slicks, by all means go for it !!

STAGING AND STARTING

There are various philosophies about staging -- putting your car in position at the starting line. Basically you have to pull your car forward until one, and then the second, of two yellow lights are lit.

One philosophy about starting is to stop JUST WHEN your car's tire triggers the second yellow. This gives you a vital inch or three of extra runup room. Some people prefer this because they can begin moving slightly earlier and thus be rolling and gaining momentum when the bottom green start lamp lights up. This momentum can be important for a solid and rapid "out of the gate" start and can help shave time. The disadvantage to this approach is that more ACTUAL PHYSICAL DISTANCE must be covered during the course of the race, even a slight amount.

The other philosophy about starting is to trigger the second yellow lamp and pull up as far forward as possible before the yellow lamp goes off again (signalling that you've gone too far and must back up slightly to re-trigger it). This provides for the absolute shortest distance from start to stop. The disadvantage is that there is far less room for a rolling start (a standing start is required) and less margin for error for disqualification. For some types of cars and conditions, however, the reduced distance can be a benefit.

In any case, effective starts in drag racing are all about timing. My recommendation is to watch a good 15-20 starts from the sidelines before even getting in your car. That way you can begin to memorize the cadence of the starting lights and get a feel for how long it takes the green lamps to light up in procession. You can also observe others' starts and see when they begin engaging brake and gas pedals in relation to the lights.

Basically for a good start, you want to hit the gas and begin letting off the brake directly when the second of the three green lights is ON. Given human physical reaction times and the time required for the car to react from gas pedal being depressed to gas and air finding its way into the cylinders to mechanical motion being produced at the rear wheels, can be a good 1/4-1/2 a second with many cars -- even cars in good tune. So some anticipation of the lights is necessary, and as a rule of thumb you should begin to hit the gas and let off the brake at the moment that the second green lamp lights up.

Next is the braking technique. Again there are many philosophies here and much depends on the car, its type and level of power, state of tune, type of transmission, etc. For the 500E, I have found that the most effective thing to do is to use the "power brake" technique. This is where you hold the brake down with firm pressure with your left foot, while gently revving the engine with your right foot on the gas pedal. When the second green light is on and getting ready to transfer over to the third green light, you let off on the brake and mash the gas pedal, launching the car.

Finding the optimal point to rev the car to, and hold it, is the secret to this technique. I have found that revs to the 2,500-3,000 RPM mark seem to provide the best combination of tractability, traction, and launch time for the 500E-E500 using sticky drag tires. However, with street tires I'd probably be down at the 2,000-2,500 RPM level so as not to spin the tires upon launch, thus blowing the overall launch.

Others find that just braking and idling the car, then mashing the throttle from idle is an effective technique. I have never really done this with the 500E. My theory is that having the engine at least in an optimal rev range at start, saves the time of getting it there from idle, not to mention provides faster responsiveness for acceleration. That's just my observation though.

From there you just travel down the track as fast as possible.

SHORT-SHIFTING

When you are going down the track, the transmission must be shifted as the revs build. Automatic transmissions shift themselves, and manuals must be shifted by the driver. Given that all 500Es are automatics, the car is going to shift for itself. UNLESS you decide to shift it manually, which is a technique that is inhereent to all Mercedes transmissions. You can essentially select your gear and decide when (up to a point) you want to up or down shift.

Again there are different schools of thought here. I prefer a "manual" approach to shifting my automatic transmission, starting it out in first gear and then going up to redline (or slightly into redline area) before upshifting into the next gear by moving the lever up one detent. I have found that this is worth 0.1-0.2 seconds over an "automatic" approach whereby the car does all of the shifting. I feel that I am able to hold the car in gear slightly longer than the car naturally is programmed or wants to on its own.


[see next message for Part 2]

[gerryvz]

{continued from Part 1}

For the novice, it's one more thing to worry about in the hubbub of starting, staging, etc. My advice for the drag racer just starting out is just to keep the car in "D" and not worry about it for the first 10 races or so. This allows you to get the feel of how things basically work and makes life simpler. One hot tip with the 500E, however, is once you are at the starting line, to move the lever down to the "2" notch and then to click it over and back (either to 2 if shifting manually or to "D" if letting the car do the work). This ensures that the car starts out in first gear and definitely will make for a faster and more positive start.

THE FINISH LINE

Before you race for the first time, you will want to be sure of where you will need to exit the track once the race is done. Somewhere at the end of the drag strip, there will be a turnoff (either on the right or left side) and you need to be aware of where this is, if you are the first finisher. If you are second, then you just follow the guy who beat you :)

Also you will need to generally be aware of where the finish line is so that you can let up on the gas well before the turnoff at the end of the track, so you have time to brake. Remember that with a stock 500E, you will be traveling 90-100 MPH at the end of the run, and you will only have 100-300 yards at the end of the track before the turnoff to slow down to a reasonable speed (10-30 MPH) to make the sharp turnoff. In any case you will need to do some serious braking to dust off speed, so be sure you know where the finish line is so that you can begin to hit the brakes and let off the gas pedal immediately after the line (not before !).

AFTER THE RACE

Normally you drive back along one side of the track back up to the staging lanes, and get in line once again. Along the way there is typically a booth, shack or person standing conspicuously out who is handing out timeslips. Be sure to pick up your timeslips and also DO NOT speed when you're driving back to the staging lanes. 20-30 MPH is fine, no more. In Portland there are always pedestrians and other cars roaming around down alongside the track and it's quite easy, especially at night in the dark, to not see a person or other car in your way. The rule is to be careful and don't let the adrenalin that hit you during the race, dictate your speed on the way back to staging.

TIPS AND TRICKS

Now, for tips and tricks on racing the 500E:

A) ICE. Go to the local Kwik-E-Mart on the way to the track. Ask Apoo if you can buy one or two bags of ice and once at the track, put them flat on top of the 500E airbox, covering as much area as possible. As you use them during the course of the night, they will melt water on your engine. This won't hurt anything, so don't worry. Keep the bags on the engine airbox for at least 30 minutes between runs.

B) TIRE PRESSURE. If you are using street tires, lower your pressure to 20-22 PSI in the rear tires. This will give then quite a bit more "bite" and contribute 0.2 seconds or so to your elapsed time (ET). Be sure before you let the air out, to ensure that your track has an air pump so that you can add air before leaving for the night. You can drive home on 20 PSI but it's not great for your tires to do so. To help with all of this, be sure to bring a tire gauge with you.

C) WAITING BETWEEN RUNS. Wait at least 30 and preferably 40-45 minutes between runs. Put your hood up to let warm air escape your engine. Hot engines are the nemesis of good ETS. So be sure to let your engine get nice and cool. This gives your ice time to work its magic on the airbox as well. You can either pull your car off to the side of the staging lanes for cooldown, or if there are a lot of people in staging, just put your car in line and move it up until your next turn. Have a handy place nearby for your icebags to remove them to when you are first or second in line and when you close your hood. Being in one of the outside staging lanes is conducive for just tossing the ice bags off to the side hurriedly when your turn comes up.

D) FUEL. This isn't totally proven with the 500E, but using 100+ octane racing fuel can't hurt above and beyond using pump gas of the 92-octane variety. You can get this from specialty shops in your area -- most major cities and suburbs have at least one purveyor of racing gas. Check with your local muscle-car shop if you don't know where to get racing gas.

It's not recommended to use "artificial" octane boosters such as toluene or canned off the shelf boosters. Just buy 5 gallons of racing gas and either use it straight or mix it with your existing fuel.

Also, you can save weight by reducing your fuel load. Meaning don't race with a full tank of gas. Each gallon of gas weighs 7 pounds; multiply this times 20+ gallons and you have 160-180 pounds for a relatively or full tank of gas. That's a lot of extra weight. Instead, siphon your gas tank out until it is dry, then add 2 gallons (or whatever you need to get you to and from the track, and use while there) of racing gas. This ensures that your existing gas is out of the system and the car is running purely on racing gas. Or siphon most of your gas out and mix with a couple of gallons of racing gas to up the octane level. I always try to bring an extra gallon of gas with me in a small gas can in case I run out, but as our track is only 4 miles from my house it's not a big deal. But for most people, they have to drive much further to the track. Plan your fuel consumption needs accordingly. If you do 6-8 runs on the drag strip, you will use far less than a gallon of gas.

E) OTHER WEIGHT. Remove your spare tire for the night, and perhaps your back seat too if you really want to lose weight. These things are easy to jettison for the night and worth a good 50-75 pounds. In addition to a dry fuel tank, you're talking 200 pounds of weight savings which can be worth a good 0.1-0.2 seconds of time on the drag strip. Not a bad reduction for not a lot of work.

F) ASR OFF. I recommend that you disable your ASR for all drag strip runs. I have found that it can cost the average driver 0.1-0.3 second as it engages and retards the timing/applies the brakes of the car when called upon to do so. In addition I found that the "snow chains" switch has no effect -- the ASR still engages under heavy acceleration. You can disable the ASR by disconnecting one of the wheel sensor lines -- I use the one directly forward of the CAN box on the passenger side -- mounted to the aft (rear) of the inner firewall. Simply unclip the plug, disconnect it, and verify that the ASR and ABS lights are on, on the dash, when you start the car. Know that the car's computer will register this disconnection of the ASR by storing a code, but this won't affect the running of the car. Also, when you reconnect the ASR/ABS sensor line, the lights on the dash will disappear next time you start the car. KNOW THAT BY DOING THIS, YOU WILL DISABLE THE CAR'S ABS SYSTEM -- YOU WILL NOT HAVE ABS CAPABILITY UNTIL YOU RE-CONNECT THE LINE. On the drag strip this is not a major deal, but you will want to reconnect the line before leaving the track and heading back out on the street.

G) OTHER APPROACHES. As stated earlier, a cooler engine with cooler air going into it in general is going to be more conducive to faster times on the drag strip. You can cool your 500E's coolant (and thus engine) by running your climate control fan on "HOT" setting while the key is turned to the ACC (accessory) position (ignition on but engine off). This will rapidly cool down the coolant by using the auxiliary ACC pump to circulate the coolant and exchange the heat out of it through the interior air vents. Using this technique, you can bring down your coolant temperature by a good 30 degrees in 20 minutes.

The danger with this approach is that you are running a major accessory off the battery, which at the high setting is a significant drain. I would only do this for 10-15 minutes or so at a time, and you want to ensure that your car is charging its battery up so that you don't weaken or kill your battery.

Anyway, hope this this primer helps and pulls together some key tenets to greater success, and lower times at the drag strip with the 500E. It should also help you to trounce additional Hondas.

Cheers,
Gerry

[Chappy]

Gerry,

Any experience with changing regualtions on vehicle prep? For example, a small road course (Little Talladega) is now requiring street cars not use Glycol in the coolant for a track day.

It was suggested using water or a como of water wetter and water as an alternative.