184: Test drive improvements

The car drove forward along the dirt road, and the wind blew in through the crack in the broken window, stinging the face a little.

Shen Xiaochuan sat in the passenger seat, his hand resting on the car door, his eyes fixed on the straight road ahead.

The sound of the engine was much steadier than before; it no longer fluctuated in volume, and the exhaust pipe no longer puffed out white smoke.

The car ran smoothly, without that jerky, stuttering feeling.

"How long can it go this time?" Shen Xiaochuan asked.

"I don't know," Lolia said, "but at least it didn't break down the moment we left."

No sooner had she finished speaking than the engine suddenly let out a "pop," the sound died down instantly, and then it stalled completely.

The car coasted for a distance and stopped on the side of the road.

Shen Xiaochuan looked down at the dashboard—the fuel was still half full, the water temperature was normal, and the battery hadn't triggered any alarms.

Lolia turned the key, the starter motor clicked a few times, and the engine started up again.

She let out a sigh of relief and slowly released the clutch.

The car began to move again.

"That's the third time," she said. "It's less than five kilometers from the workshop to the Main Hall, and it's already stalled three times."

Shen Xiaochuan nodded: "Where's the problem?"

"The carburetor," Lolia bit her lip. "The Thunder Crystal powder conducts heat too quickly, the cylinder block temperature gets too high, and the air-fuel mixture keeps alternating between rich and lean. I've adjusted the intake manifold angle twice, but it's still not working."

She tapped the roof of the car: "I thought adding insulation would be enough, but it turns out the heat just accumulates on the cylinder head. Now we can only keep going by repeatedly restarting the engine."

Shen Xiaochuan glanced at her. Her face was stained with oil, and the hair on her forehead was matted with sweat, sticking to her face.

Her eyes were bright, but she was very tired.

"Did you record the data?" he asked.

"I did." She pulled a crumpled piece of paper from under her seat, which had drawings and was filled with numbers. "I marked down the RPM, oil pressure, and exhaust temperature every time it stalled. Look here—" She pointed to a line of text with her pen. "After exceeding 3,000 RPM for thirty seconds, the cylinder head temperature rises above 320 degrees, and then the fuel supply goes haywire, cutting the ignition."

Shen Xiaochuan took the paper, looked at it, and handed it back: "It's not that your skills are lacking."

"But this is the first car." Her voice dropped. "It can't even run ten kilometers; what will others think? People outside are saying we built a metal shell that looks good but doesn't work."

"Who said that?"

"A lot of people," she said with a wry smile. "Yesterday, someone passing by stood outside and shouted, 'Can this car even get on the road? A donkey could pull you back faster.'"

Shen Xiaochuan didn't laugh. He opened the door, got out, walked to the front of the car, and lifted the hood. The metal was still hot to the touch.

He touched the connection point of the cylinder block and then glanced at the location of the carburetor.

"How much Thunder Crystal powder did you add?"

"Two percent."

"Too much." He stood up. "The heat conduction is too strong, and the heat dissipation can't keep up. You need to reduce the ratio, add another layer of ceramic coating to block some of the heat, and don't let it all transfer out."

"Reduce it to how much?"

"Try 0.7 first," he said. "Also, redo the intake manifold; the bends are too sharp, causing unstable airflow. Make a double-layered shell with a gap in the middle to act as insulation."

Lolia took out her notebook and quickly wrote it down.

"Also, reduce the ignition timing by five degrees." Shen Xiaochuan pointed to the distributor. "You're firing too early right now; the high temperature and high pressure combined make it prone to knocking."

She nodded and continued writing.

"How long will these changes take?"

"Three days," she said, "if the parts can be made overnight."

"Make a list of the Materials, and I'll have someone deliver them." Shen Xiaochuan patted the dust off his hands. "You don't need to make it perfect the first time; the first car is meant for testing anyway. When the steam engine first came out, the boiler exploded seven times before it could run eight kilometers."

He looked at her: "This car of yours is already better than that."

Lolia looked up at him for two seconds, the corners of her mouth twitched, but she didn't say anything.

The two got back into the car. Shen Xiaochuan sat back in the passenger seat and fastened his seatbelt.

"Let's go," he said. "Back to the workshop."

On the way back, it stalled two more times. The last time was at the bottom of a slope, where the car got stuck in a mud pit and almost couldn't get out. Lolia got out to use a crowbar to wedge under the tires, and Shen Xiaochuan pushed from behind. By the time they finally climbed out, it was already dark.

A kerosene lamp hung at the entrance of the workshop, its shade rattling in the wind. Several blacksmiths were still working, the light from their welding torches flickering in the night.

Before leaving, Shen Xiaochuan said: "Don't stay up too late. If the car breaks, it can be repaired, but you can't collapse."

She gave a hum of acknowledgment and turned to enter the workshop.

Three days later, at six in the morning.

The plaza in front of the Main Hall was empty, save for soldiers walking back and forth.

Shen Xiaochuan stood on the steps, holding a bowl of hot porridge, eating while looking toward the workshop.

At 6:17, the sound of an engine came from afar.

A car drove out from the morning mist.

The car body was still painted in camouflage, the wheels were aligned, and reinforcement strips had been added to the roof. The exhaust pipe didn't smoke, and the sound was deep and steady, like a beast walking slowly.

The car stopped at the bottom of the steps, and Lolia rolled down the window.

"Did it work?" Shen Xiaochuan asked.

"It worked." She looked very tired, but her eyes were bright. "New ratio, new structure. I ran a fifty-kilometer test, reached a maximum of 4,200 RPM, and it didn't cut ignition once the whole way."

Shen Xiaochuan put down his bowl and walked down the steps.

He walked around the car once and tapped the hood: "It sounds very smooth."

"I replaced it with a double-layered heat-insulating shell and adjusted the angle of the intake manifold," she said. "The Thunder Crystal powder was reduced to 0.7, and the cylinder head temperature is controlled within 240 degrees. The ignition timing was reduced, and the knocking is gone."

Shen Xiaochuan opened the passenger door and sat inside.

The interior still had cloth seats, but a simple tachometer had been added to the dashboard. The steering wheel was wrapped in non-slip leather, and the pedals had been replaced with alloy ones.

"Want to take it for a spin?" she asked.

"No," Shen Xiaochuan shook his head. "To the Hospital."

"Is Lilia running a fever?"

"She had a fever of 39 degrees last night, and it wouldn't break," he said. "Your sister called and said the child is coughing so much she can't sleep, so we need to go see her."

Lolia nodded and turned the key.

The engine started on the first try, idling steadily with no strange noises.

The car slowly drove out of the Main Hall area. As it passed the trade street, a few early-rising vendors looked up. Someone recognized it as the metal-shell car that kept breaking down a few days ago and started pointing and whispering.

"Broken again?" an old man muttered.

"It didn't stop this time," a young man next to him said. "It sounds quite steady."

The car drove through the city and onto the main road leading to the Hospital. The road surface was smooth, with grass planted on both sides, and the wind blowing in carried a chill.

Shen Xiaochuan glanced at the tachometer: "Try accelerating."

Lolia pressed the accelerator lightly. The car picked up speed smoothly without any stuttering. After passing the intersection, the speed reached sixty, and the car body remained steady.

"Much better than last time," he said.

"It won't just stop whenever it wants this time," she said, holding the steering wheel, her tone calm. "As long as there's fuel and the road doesn't end, it can keep running."

As they spoke, they arrived at the Hospital.

The car stopped at the entrance of the emergency building. Two nurses pushed a stretcher out, and upon seeing them, they immediately walked over.

"The patient is in the observation room on the second floor," one nurse said. "She just finished her IV, the fever has gone down a bit, but she's still coughing."

Lolia got out and followed them in. Shen Xiaochuan stayed in the car and opened the window to get some air.

Less than ten minutes later, Lolia came out supporting her younger sister. Lilia was wearing a Hospital gown, her face pale, with a fever-reducing patch on her forehead, and she was a bit unsteady on her feet.

"Get in," Lolia said. "Let's go home and lie down."

Shen Xiaochuan helped her into the back seat and covered her with a blanket.

"Are you cold?" he asked.

Lilia shook her head, closed her eyes, and let out a soft sound.

The car started up again. Shen Xiaochuan looked back at Lilia once, then looked at the sister driving in front.

"You haven't slept well for three days?" he asked.

"I slept," Lolia said. "I just dozed off at the workbench when I got tired."

"Is it worth it? For a car."

"This isn't just a car," she said softly. "This is a starting point. You said all technology starts from something crude. I want the first starting point to run a little more steadily."

Shen Xiaochuan didn't say anything more.

The car left the Hospital and returned along the same road. The sun shone on the roof, and the metal began to heat up.

The farmland on the side of the road was green, and the shadows of the distant watchtowers fell obliquely onto the ground.

When turning a corner, Shen Xiaochuan suddenly spoke: "Next time, let's make a truck."

"For hauling cargo?"

"It can also carry people and equipment," he said. "When the roads are built to the border in the future, this vehicle will need to be able to cross mountains."

The corners of Lolia's mouth lifted slightly: "That will require an engine with a larger displacement."

"You design it, I'll provide the Materials."

She nodded, her hands holding the steering wheel steadily.

The car continued forward, the tires rolling over the road surface, making a low friction sound. Lilia in the back seat fell asleep amidst the bumps, her breathing gradually becoming steady.

Shen Xiaochuan leaned back against the seat, watching the scenery flying by outside the window.

In the distance, the silhouette of Skydome City was clearly visible in the morning light. Smoke rose from the city walls, and the flag of gears and flames fluttered in the wind.

He raised his hand and touched the copper gear pendant on his cuff.

The car did not stop.