How to get your riced car to do 14sec quarter mile
Discussion
SCC Technical Assistance Program
By Dave Coleman
Photography: Henry DeKuyper
Dear Sport Compact,
First off, let me just say that your mag is the best my friend is subscriber and I steel his copy every month before he even reads it now he wants to kick my ass but I told him instead of fighting we should have a heads up doorslammer only problem he has a Mazda MX-6 with the turbo motor and my Sentra cant keap up I mean my car is fixed up and all but I spend most my money giving it the looks I have full aero and pearl paint and lower three inches and even sub dubs for rims I spend so much on paint and body I have not money left to beat my friends turbo and now he says if I loose hes going pound my ass into the ground can you help me go faster thanks you guys rock.
Scared to Race
El Monte, Calif.
--------------------------------------------------------------------------------
Part 1: Free Speed
Every month we get hundreds of tech letters varying from the simple "how do I fit a supercharged Prelude engine in my '73 Civic" to the nearly impossible "how do I get vanilla milkshake stains out of my back seat."
Of these hundreds, our tradition is to cherry pick the easiest to answer, write a trite response, print it in our letters column and go home early.
No more.
Our new editor is afraid that if he doesn't bark a few orders every now and then, nobody will know he's doing his job. And so we launch the new Sport Compact Car Technical Assistance Program, wherein we cherry pick a far more difficult letter and not only offer a suggestion, but actually take on the task of solving the problem ourselves. So much for that afternoon nap.
With this letter, we launch our technical assistance program as this is such a common problem. Looks come first and performance (and your wallet) suffers. Hoping to save a faithful reader from a serious ass pounding, we take Mr. To Race's car to the track for a day and let three engineers and an art history major give it their all. The only limitation given to our crack technical assistance staff has a total budget of $0.
Step 1: BaselineBefore suggesting modifications, it's critical we know where Mr. To Race is starting. His car is a 2001 Sentra SE with the venerable SR20DE powerplant. This is the newest variant of the SR20, with a close-coupled cat, roller rockers, and a four-counterweight crank. None of this matters at all, because without money, you can't extract the tremendous potential of this engine. The car also has heavy 19-inch wheels, cut springs and one of the most aggressive body kits we've ever seen. We find three kittens and a squirrel cowering in fear inside one of the massive front air intakes.
Step 1: Baseline
Curb Weight: 2,762 lbs
1/4 Mile:16.3 @ 84.0 mph
60-foot:2.9 sec.
0-60 mph:8.6 sec.
=======================================
Step 2: 15-inch wheels
The 19-inch wheels are the first obvious problem. With a 225/35ZR-19 tire at each corner, each of these giant, round testaments to Mr. To Race's masculinity weighs a shocking 46 lbs. In addition, their tall, 25.2-inch rolling diameter effectively makes the gearing taller.
Now, before you point out that changing wheels costs money, let us remind you that Sentras don't come with 19-inch wheels. Therefore, it stands to reason that Mr. To Race has a set of smaller wheels and tires sitting in his garage somewhere. Since Mr. To Race has a Rottweiler, we couldn't actually get into his garage, but we did manage to pirate a set of 15-inch Infiniti G20 wheels from an uninvolved third party. Wrapped in 195/60R-15 Firestone rubber with a treadwear rating of 500, these rocks are only slightly smaller overall, at 24.9 inches, but they're 13 lbs lighter at each corner. The reduced weight and rotational inertia drop the quarter-mile time by 0.3 seconds.
Step 2: 15-inch Wheels
Curb Weight:2,707 lbs
1/4 Mile:16.0 @ 85.5 mph
60-foot:2.8 sec.
0-60 mph: 8.1 sec.
=======================================
Step 3: Stripped InteriorAsk anyone who has ever drag raced Mom's Accord and you'll learn our next trick. A stripped interior not only saves 273 lbs, it also lets everyone know you're serious. Many amateur drag racers stop at simply removing the passenger's seat and spare tire, but we remove everything: headliner, sunroof, carpet, dashboard, six-disc in-dash CD changer. For expediency, we leave the tar paper stuck to the floorboards, but Mr. To Race will find another 15 lbs of weight savings if he takes the time to chisel it off. As an added bonus, we also remove the antenna to reduce aerodynamic drag. The mods are good for another 0.5-second improvement.
Step 3: Stripped Interior
Curb Weight:2,434 lbs
1/4 Mile:15.5 @ 82.5 mph
60-foot:2.7 sec
0-60 mph:7.5 sec
=======================================
Step 4: Free Horsepower
Whoever said horsepower costs money just didn't have the kind of clear-thinking, innovative tuners we unleashed on Mr. To Race's car. The intake, exhaust and underdrive pulley are three standard first modifications to any car, but our crack team figured out how to get all the benefit of these expensive parts without spending a dime. The most obvious free horsepower mod is to remove the exhaust. This makes the engine extremely loud and, as you know, noise equals power. The catalytic converter is integrated into the exhaust manifold, however, so technically, this is a CARB-legal modification.
Next, in the grand Pontiac tradition, we fashioned a ram-air intake by removing the bottom half of the air filter box, taping the filter into the upper half, and sticking the whole thing up into the airflow. Finding airflow, of course, means removing the hood, but no hood at all is even lighter than a carbon-fiber hood, so we think Mr. To Race will appreciate the aesthetic one-upmanship of this ultra-extreme race mod.
Finally, in an effort to reduce parasitic losses from the belt-driven accessories, we simply remove the accessories themselves. The air conditioner, obviously, is unnecessary on a racecar, but less obvious is the redundancy of the alternator. When the car is only running for a quarter mile at a time, there's no need to constantly charge the battery. To reduce the electrical load on the battery, we also remove the headlights and taillights, leaving more voltage for the engine itself.
Were this a normal project car, we would dyno test each of these modifications, but dyno testing would make this test run well into the evening, and as you know, the "Dukes of Hazzard" comes on at 8 p.m.
Fearing our increased power might turn our Firestones to smoke, we air them down to 25 psi to increase the size of the contact patch for better launches. Even with the giant contact patches, our 60-foot time increases by 0.1 seconds, but the added power and reduced aerodynamic drag from a last-minute removal of the windshield wipers knock another 0.3 seconds from our e.t.
Step 4: Free Horsepower
Curb Weight:2,252 lbs
1/4 Mile:15.2 @ 89.6 mph
60-foot:2.8 sec.
0-60 mph:7.1 sec.
=======================================
Step 5: Chop Shop
Nobody said this was going to be easy. The MX-6 Turbo is some stiff competition, and with Mr. To Race facing bodily harm if he loses, we decide desperate measures are justified. Say goodbye to the body kit.
We're sure to check every orifice for puppies and kittens before carefully removing the air dam with a nearby curb. Feet, saws and angst-ridden fists make very effective tools for quickly and efficiently removing the rest of the body kit.
With the aerodynamic accoutrements out of the way, we return our focus to weight. Fenders don't weigh much, but the sight of your smoking front tires just sitting out there for all the world to see really intimidates the competition, so naturally we remove them. Power windows and side impact beams have made modern doors exceptionally heavy, so again, they have to go. So does the trunk. And the hood latch. And every brace and bracket we can find. And the horn.End result: curb weight drops below 2,000 lbs, the e.t. hits the 14s.
Step 5: Chop Shop
Curb Weight:1,904 lbs
1/4 Mile:14.7 @ 90.7 mph
60-foot:2.8
0-60 mph:6.3
=======================================
Step 6: Details
At this point the car looks thoroughly stripped, but close inspection reveals countless unnecessary items can still be removed. The relays for the fan, horn, fog lights and HVAC fan, for example, are still in place, even though there's nothing for them to switch on. The windshield and rear window are easy to forget, being clear and all, but they are, in fact, quite hefty. And then there's that entire car just hanging out there behind the rear wheels.
Nothing actually happens back there, there's no engine, no suspension mounting points, nothing of any performance value. We can't find any reason why the car shouldn't just stop existing after the rear wheels. If you ever want to make something stop existing, the Milwaukee Sawzall is the tool. Oh, the satisfaction.
Uh, anyway, while we're back there, we notice the rear tires are bigger than they need to be now that there's nothing for them to hold up. Space-saver spare tires are great budget skinnies, but Mr. To Race only has one in his car. Again, we're able to pirate a second from a G20. Think about it: The G20 needs four spares now that we have its tires, so the one spare left in the trunk isn't doing anybody any good.
Step 6: Details
Curb Weight:1,760 lbs
1/4 Mile:14.4 @ 92.2 mph
60-foot:2.6 sec.
0-60 mph:6.0 sec.
=======================================
Step 7: Styling
Running 14.4 in the quarter, we're pretty sure Mr. To Race's ass is safe from pounding, but now we've created another problem. Because of how his car was originally equipped, his goals were obvious, and now, looking like a theft recovery, women will not be impressed. A solution that causes another problem is no solution at all, so we convened for a brainstorming session. From this swirling cloud of brain, Dan Barnes emerges, Sawzall in hand, and utters three simple words. "Chicks dig convertibles."
Step 7: Styling
Curb Weight:1,674 lbs
1/4 Mile:14.3 @ 93.2 mph
60-foot:2.6 sec.
0-60 mph:5.8 sec.
_______
By Dave Coleman
Photography: Henry DeKuyper
Dear Sport Compact,
First off, let me just say that your mag is the best my friend is subscriber and I steel his copy every month before he even reads it now he wants to kick my ass but I told him instead of fighting we should have a heads up doorslammer only problem he has a Mazda MX-6 with the turbo motor and my Sentra cant keap up I mean my car is fixed up and all but I spend most my money giving it the looks I have full aero and pearl paint and lower three inches and even sub dubs for rims I spend so much on paint and body I have not money left to beat my friends turbo and now he says if I loose hes going pound my ass into the ground can you help me go faster thanks you guys rock.
Scared to Race
El Monte, Calif.
--------------------------------------------------------------------------------
Part 1: Free Speed
Every month we get hundreds of tech letters varying from the simple "how do I fit a supercharged Prelude engine in my '73 Civic" to the nearly impossible "how do I get vanilla milkshake stains out of my back seat."
Of these hundreds, our tradition is to cherry pick the easiest to answer, write a trite response, print it in our letters column and go home early.
No more.
Our new editor is afraid that if he doesn't bark a few orders every now and then, nobody will know he's doing his job. And so we launch the new Sport Compact Car Technical Assistance Program, wherein we cherry pick a far more difficult letter and not only offer a suggestion, but actually take on the task of solving the problem ourselves. So much for that afternoon nap.
With this letter, we launch our technical assistance program as this is such a common problem. Looks come first and performance (and your wallet) suffers. Hoping to save a faithful reader from a serious ass pounding, we take Mr. To Race's car to the track for a day and let three engineers and an art history major give it their all. The only limitation given to our crack technical assistance staff has a total budget of $0.
Step 1: BaselineBefore suggesting modifications, it's critical we know where Mr. To Race is starting. His car is a 2001 Sentra SE with the venerable SR20DE powerplant. This is the newest variant of the SR20, with a close-coupled cat, roller rockers, and a four-counterweight crank. None of this matters at all, because without money, you can't extract the tremendous potential of this engine. The car also has heavy 19-inch wheels, cut springs and one of the most aggressive body kits we've ever seen. We find three kittens and a squirrel cowering in fear inside one of the massive front air intakes.
Step 1: Baseline
Curb Weight: 2,762 lbs
1/4 Mile:16.3 @ 84.0 mph
60-foot:2.9 sec.
0-60 mph:8.6 sec.
=======================================
Step 2: 15-inch wheels
The 19-inch wheels are the first obvious problem. With a 225/35ZR-19 tire at each corner, each of these giant, round testaments to Mr. To Race's masculinity weighs a shocking 46 lbs. In addition, their tall, 25.2-inch rolling diameter effectively makes the gearing taller.
Now, before you point out that changing wheels costs money, let us remind you that Sentras don't come with 19-inch wheels. Therefore, it stands to reason that Mr. To Race has a set of smaller wheels and tires sitting in his garage somewhere. Since Mr. To Race has a Rottweiler, we couldn't actually get into his garage, but we did manage to pirate a set of 15-inch Infiniti G20 wheels from an uninvolved third party. Wrapped in 195/60R-15 Firestone rubber with a treadwear rating of 500, these rocks are only slightly smaller overall, at 24.9 inches, but they're 13 lbs lighter at each corner. The reduced weight and rotational inertia drop the quarter-mile time by 0.3 seconds.
Step 2: 15-inch Wheels
Curb Weight:2,707 lbs
1/4 Mile:16.0 @ 85.5 mph
60-foot:2.8 sec.
0-60 mph: 8.1 sec.
=======================================
Step 3: Stripped InteriorAsk anyone who has ever drag raced Mom's Accord and you'll learn our next trick. A stripped interior not only saves 273 lbs, it also lets everyone know you're serious. Many amateur drag racers stop at simply removing the passenger's seat and spare tire, but we remove everything: headliner, sunroof, carpet, dashboard, six-disc in-dash CD changer. For expediency, we leave the tar paper stuck to the floorboards, but Mr. To Race will find another 15 lbs of weight savings if he takes the time to chisel it off. As an added bonus, we also remove the antenna to reduce aerodynamic drag. The mods are good for another 0.5-second improvement.
Step 3: Stripped Interior
Curb Weight:2,434 lbs
1/4 Mile:15.5 @ 82.5 mph
60-foot:2.7 sec
0-60 mph:7.5 sec
=======================================
Step 4: Free Horsepower
Whoever said horsepower costs money just didn't have the kind of clear-thinking, innovative tuners we unleashed on Mr. To Race's car. The intake, exhaust and underdrive pulley are three standard first modifications to any car, but our crack team figured out how to get all the benefit of these expensive parts without spending a dime. The most obvious free horsepower mod is to remove the exhaust. This makes the engine extremely loud and, as you know, noise equals power. The catalytic converter is integrated into the exhaust manifold, however, so technically, this is a CARB-legal modification.
Next, in the grand Pontiac tradition, we fashioned a ram-air intake by removing the bottom half of the air filter box, taping the filter into the upper half, and sticking the whole thing up into the airflow. Finding airflow, of course, means removing the hood, but no hood at all is even lighter than a carbon-fiber hood, so we think Mr. To Race will appreciate the aesthetic one-upmanship of this ultra-extreme race mod.
Finally, in an effort to reduce parasitic losses from the belt-driven accessories, we simply remove the accessories themselves. The air conditioner, obviously, is unnecessary on a racecar, but less obvious is the redundancy of the alternator. When the car is only running for a quarter mile at a time, there's no need to constantly charge the battery. To reduce the electrical load on the battery, we also remove the headlights and taillights, leaving more voltage for the engine itself.
Were this a normal project car, we would dyno test each of these modifications, but dyno testing would make this test run well into the evening, and as you know, the "Dukes of Hazzard" comes on at 8 p.m.
Fearing our increased power might turn our Firestones to smoke, we air them down to 25 psi to increase the size of the contact patch for better launches. Even with the giant contact patches, our 60-foot time increases by 0.1 seconds, but the added power and reduced aerodynamic drag from a last-minute removal of the windshield wipers knock another 0.3 seconds from our e.t.
Step 4: Free Horsepower
Curb Weight:2,252 lbs
1/4 Mile:15.2 @ 89.6 mph
60-foot:2.8 sec.
0-60 mph:7.1 sec.
=======================================
Step 5: Chop Shop
Nobody said this was going to be easy. The MX-6 Turbo is some stiff competition, and with Mr. To Race facing bodily harm if he loses, we decide desperate measures are justified. Say goodbye to the body kit.
We're sure to check every orifice for puppies and kittens before carefully removing the air dam with a nearby curb. Feet, saws and angst-ridden fists make very effective tools for quickly and efficiently removing the rest of the body kit.
With the aerodynamic accoutrements out of the way, we return our focus to weight. Fenders don't weigh much, but the sight of your smoking front tires just sitting out there for all the world to see really intimidates the competition, so naturally we remove them. Power windows and side impact beams have made modern doors exceptionally heavy, so again, they have to go. So does the trunk. And the hood latch. And every brace and bracket we can find. And the horn.End result: curb weight drops below 2,000 lbs, the e.t. hits the 14s.
Step 5: Chop Shop
Curb Weight:1,904 lbs
1/4 Mile:14.7 @ 90.7 mph
60-foot:2.8
0-60 mph:6.3
=======================================
Step 6: Details
At this point the car looks thoroughly stripped, but close inspection reveals countless unnecessary items can still be removed. The relays for the fan, horn, fog lights and HVAC fan, for example, are still in place, even though there's nothing for them to switch on. The windshield and rear window are easy to forget, being clear and all, but they are, in fact, quite hefty. And then there's that entire car just hanging out there behind the rear wheels.
Nothing actually happens back there, there's no engine, no suspension mounting points, nothing of any performance value. We can't find any reason why the car shouldn't just stop existing after the rear wheels. If you ever want to make something stop existing, the Milwaukee Sawzall is the tool. Oh, the satisfaction.
Uh, anyway, while we're back there, we notice the rear tires are bigger than they need to be now that there's nothing for them to hold up. Space-saver spare tires are great budget skinnies, but Mr. To Race only has one in his car. Again, we're able to pirate a second from a G20. Think about it: The G20 needs four spares now that we have its tires, so the one spare left in the trunk isn't doing anybody any good.
Step 6: Details
Curb Weight:1,760 lbs
1/4 Mile:14.4 @ 92.2 mph
60-foot:2.6 sec.
0-60 mph:6.0 sec.
=======================================
Step 7: Styling
Running 14.4 in the quarter, we're pretty sure Mr. To Race's ass is safe from pounding, but now we've created another problem. Because of how his car was originally equipped, his goals were obvious, and now, looking like a theft recovery, women will not be impressed. A solution that causes another problem is no solution at all, so we convened for a brainstorming session. From this swirling cloud of brain, Dan Barnes emerges, Sawzall in hand, and utters three simple words. "Chicks dig convertibles."
Step 7: Styling
Curb Weight:1,674 lbs
1/4 Mile:14.3 @ 93.2 mph
60-foot:2.6 sec.
0-60 mph:5.8 sec.
_______
Gassing Station | General Gassing [Archive] | Top of Page | What's New | My Stuff