Lotus Seven: Starting the Seven after an engine rebuild
When last reported, The engine was in and had been started. Let's see, I have been without a Seven since last Thanksgiving, seven months. My wife was so excited for me, she drew a full size picture of the Seven using sidewalk chalk on the driveway, with the caption "Its back!". I think the neighbors knew, with all the reving going on.
Break in was 15 minutes at 2200 rpm. While my wife sat in the driver's seat, trying to keep it running, I was dancing around setting the timing and balancing the carbs. There were a multitude of problems but it did run. She had a timer and shut it off at the right time.
The car would not idle and it was tough keeping it running at the 2200 rpm. I have the timing set at about six BTDC, and I was surprised when my engine builder was as concerned about retarded timing and how it helps blow head gaskets. I figured the problem was carbs, but I wanted to drive it for the suggested one hour before taking it to be dyno tuned. So I started checking things.
After letting the car cool, I checked the idle mixture screws on the 40 DCOEs and found one of them only open about half a turn. I set them all at the optimum one and a half turns open and the car ran much better, drivable in fact! Who could resist a quick turn around the block? The two boys piled in, with their hips barely fitting in the passenger seat. A great time was had by all.
The car will now idle reliable at 1100 rpm, still a bit high. Occasionally it will drop to 800 rpm but then bounce back up. If I set the idle stop lower the engine dies. The oil pressure is running about 5 psi higher, and my engine builder admits to doing a little extra here. And the car seems to run cooler than before. I can actually tell when the thermostat is cycling. I expected it to run hotter during breakin.
I contrived to go on a family outing with my wife following in the family minivan. We drove for around, with the two boys trading places in the Seven. Interesting comments. The three year old, Ryan, told me it was difficult to talk in the Seven. The five year old, Dustin, wanted to know what all the switches were for, and was fascinated to see the engine fan going on and off as I still had the bonnet off.
I retorqued the head, intake and exhaust manifold bolts. I set the valve lash, .020 and .022, and was surprised how much a couple had changed. Carbs were still balanced, as checked with the trusty Unisyn. I think this tool has been with me the longest, me having cut my teeth on the four one barrels on the Corvair Corsa.
Time for a hill climb, and some wide open throttle.
There is a back road up the hill near the house. It was evening, little traffic, and the road tight, twisty and increadibly steep. The car was amazing. I was not going much faster than 45 -50mph. It felt like I was on the back of a powerful, wild amimal that was scrabbling and scratching its way up the hill and I was only holding on for dear life! I puttered down the hill to home. The entire wait and all the effort now worth it.
I have an appointment with the local chassis dyno guru this evening. Charlie Rockwell is well known in these parts as being a wizard at tuning cars. And he has a chassis dyno to make it easier. Mike Stimson, the engine builder, will be coming along. I guess he is curious about the power.
Later I measured my 0-60 mph time at 4.7 seconds, without abusing the clutch!