The car had a partly successful though exciting outing two nights ago when I took it for a first drive. After getting a throttle return spring mounted and secured, as well as finding some bushings to eliminate the slop from size mismatch in the throttle rod/lever, the car was road worthy enough for a real test.
Working the throttle I discovered the secondary blades don't have an adjustable stop, which means the blades tend to get bound up when they slam closed, making the throttle action jerky as the blades engage. I will have to modify the lever arm to include a throttle stop so the blades don't jam closed in the back, requiring a spike in pedal effort when you start to actuate them. I'll get to that in the future, but right then a road test to restore morale was in order. I tied up all the wires in the engine bay to keep them off of the exhaust, topped up the air in the tires, and hit the road.
After throwing my garage fire extinguisher in the back seat, (Norm Abram's admonishments about shop safety always did stick with me) I did a quick lap around the neighborhood as a shakedown. The fuel map I have currently errs on the side of rich at around 10-12 AFR, but I could only get into the primaries of the 4-bbl progressive throttle body in my little neighborhood with a 35 mph speed limit. After getting the map a little closer up to around 30% throttle when the progressive secondary blades open, I decided it was time for a little more open road.
The sun had set when I started my first lap around the block, so by now it was dark. Immediately I could tell the accel enrichment needed a bit more fuel, as it had a tip-in stumble. I cruised along at 45 under constant load with my brother watching AFRs as I slowly built to 60. Everything was looking good at 60 with AFRs on the rich side at 11-12:1, so I gave it a bit more throttle to pop open the secondaries. It immediately bogged down and the AFR fell to 9-10.
I backed out of it and immediately heard clunking from somewhere in the car. I slowed down a bit more, the clunking stopped but it sounded like something flapping underneath so I pulled over to have a look. As it turns out, I had neglected to reattach the emergency brake cables I removed to get to the fuel lines, and the pivot bar had come loose (the clanking I heard) to be lost somewhere on the side of the road forever. I tucked the cables up and did a quick electrical tape job to keep them off the road, and prepared to head back home, about 2 miles away.
The car cranked over hard. The hot starting timing still had some issues, but it was more difficult to get to catch than usual. Worried, I finally got it to start and headed home. As I crested the hill I heard another clang, so I slowed to pull into a feed store that was closed for the evening. As I slowed for the corner, it sputtered and died. The hill was enough to glide into the parking lot, where I tucked another cable back up into the frame.
When I tried for a restart, no dice. It just wouldn't catch. I'd been cranking it a lot that day, so I figured some extra battery voltage would get it going and I called for backup. A quick jump and it was going again. Not wanting to risk it dying again, I punched it to get the 2 miles home. As I climbed up out of the mini-valley I just descended into, the car started sputtering and my AFR gauge read lean. I crested the hill barely and as I started sloping down the car picked up again.
Fuel. I needed fuel. I would make it down the hill but I'd never make it back up the next. I coasted to a stop and waited for my support vehicle to catch up to me. My mom looked at me and rolled her eyes when I said it was out of gas and went to fetch me some. A few minutes later I'd popped another 5 gallons of 93 octane in it and off it went.
I had the argument with my brother before I left, he said I should probably fill up. I had put 6 gallons in the empty tank when I first filled it, and I figured there was no way I had gone through that much gas, so I said I'd fill up when I got back.
Well, I hadn't used 6 gallons. But while it will fill up and idle with just 1 gallon in the tank on a flat driveway, add any motion to that and you suddenly need about 3 gallons to reliably draw fuel from the tank, and I had easily burned three gallons in my idle and tuning time.
Lesson learned. I need to fix my emergency brake cable, loom up the wires, put in a secondary throttle stop, and listen to my brother when he says I should put more fuel in it.
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