(From an undated issue of the H-Modified Racing Club Newsletter)
H MOD Over the Hill Gang Newsletter)
The following is the report read by Martin Tanner at the annual H Modified Banquet, at the Oakland County Sportsman’s Clubhouse on July 30:
In case any of you Formula Vee fellows think you have it easy because you are not allowed to modify your machines, or in case any of you H Modified chaps think it is fun to tinker with a homemade car, I will read this paper which I plan to present next week to the International Society of Automotive Engineers.
When you first design and build a complete car, you have occasional malfunctions, but as you encounter each one, you can draw a moral from your experience.
I will explain a few of the malfunctions I encountered with the first cars I built and also explain the morals I gained from them.
When I completed my first car, I entered a race at Harewood in Canada. Another chap and I jumped into the car, together with a toothbrush and a tin box of tools and took off. No tow car.
At midnight somewhere this side of St. Thomas, the engine made a noise like a string of firecrackers, and then quit running altogether. We pushed it into town and took off the camshaft cover and found that the top of one of the Italian cam followers had been bashed in by the camshaft. We found an old man out in the country – by one o’clock in the morning – who sawed off a piece of a steamboat propeller shaft and made it into a cam follower. He finished it at four o’clock that morning. We got up at 6:30 and drove to the race.
Now, the moral to that story is: Italian cam followers are not as good as Italian spaghetti.
At the race course the next day, two friends arrived. One of them re-set the timing and installed new spark plugs. The other checked the wheel bearings, adjusted the steering tie rods and the brakes. My other friend changed the carburetor jets to give a slightly better mixture. So I started out in the race very well…until the beginning of the second lap. Then I ran out of gas.
The moral to that story is: Always have someone on your crew who doesn’t know anything about automobiles, such as your wife. She’ll probably remember to put in gasoline.
The next race, a month later, we drove as far as London, Ontario, when the engine sounded as if someone was pounding on it with a sledge happer. We towed the car to Jarvis, propped it up, took off the oil pan and found that the number four connecting rod bearing was chewed up. Surprisingly enough, nobody in Jarvis had a new Fiat rod bearing ten thousandth over. So that was the end of that expedition.
We discovered later that the connecting rod itself had been out of alignment when I installed it.
The moral is: If something doesn’t fit in the first place, it probably won’t fit better, later.
The next race was three weeks later. I got there, and the car ran very nicely. For about 3 ½ laps. The noise, this time, was as if a man were chopping up a tin can with a hatchet.
When we got home we found that the trouble was in the oil sump baffle. This oil sump was aluminum casting and the baffle was a sheet of formed aluminum and, according to the manufacturer, was meant to be fastened to the casting with metal screws. What happened was that those screws became unscrewed. The baffle shook loose and the crankshaft had wrapped it all up like a hair ribbon in an egg beater.
The moral to that story is: Metal screws won’t hold in a casting even if the manufacturer thinks they will.
The next lesson I learned was right here near my home in Saginaw – going to Flint and back. A chap went along with me in my Healey and I had driven the little car to Flint and we were on the way back within a few miles of Saginaw – when the whole car shuddered and skidded to a stop. My friend towed me home and I found that night what happened. The tower shaft which drives the camshaft had seized in its bronze bearing. The camshaft stopped revolving but the pistons didn’t. The pistons whacked at the valves and they in turn knocked the camshaft out of its bearings by the roots. Ten teeth had ripped off the tower gear and 13 teeth were gone from the cam gear. That chap came over the next night and I told him what had happened and he said, “Oh, thank goodness that was all. I was afraid it might have been something serious!”
The moral is: Don’t let anything trivial happen to your engine.
In the next race, I can’t remember where, I was sailing around fine. In the 4th lap the engine almost screamed – I was revving up to 9,000 in the 4th gear. Then some chap in a dog of a car passed me on the straight-a-way. I looked at the trees and they weren’t going fast at all. So I looked at the floor and it was covered with a little pile of black stuff that looked like peat moss; it means your clutch lining has disintegrated and your engine is no longer connected to the rear wheels.
The moral is: If you beef up your engine, be sure to let your clutch know about it.
(There’s a gap here, with the explanation that the remainder of the “report” will be spread across the next two issues. Well…I can’t find part two…so I’m picking up with part three from an issue that has “March 1967” handwritten on the cover.)
MARTIN TANNER REPORT
PART 3
In the next race on the third lap, I managed to get out in front. Then on the Straight-away Ollie Schmidt passed me. As we arrived at the next corner and he properly braked down, I dove right in, slid around, and got up beside him planning to out accelerate him coming out of the turn. I shifted down to second gear, and pushed hard on the accelerator and the motor revved up to 9,000 and, just as I planned, I shot out ahead of him. But then there was a noise in my engine. It sounded like a waiter in a hotel dining room with a large tray of dishes and glasses and going through the wrong door. The autopsy showed that the connecting rod had come apart, chopped a hole in the side of the engine, smashed the crankcase, busted the oil sump and twisted itself up like a pretzel.
The moral is: There is a limit to which any engine can be revved but you don’t know ahead of time what that limit is.
I rebuilt the engine and as an added refinement I fixed the intake manifolds so they would be cooler. I wrapped them with 15 layers of asbestos like a mummy, to be sure to keep the heat out. Down at Akron I was rushing around in 3rd place when the engine coughed two times and quit. I had done such a good job of insulation that all the heat was effectively retained in the aluminum manifold. It melted apart and fell into the belly pan.
The moral to that story is: If something is insulated to keep the heat out – it will probably also keep the heat in.
Once I was driving from the boat dock to the Elkhart. Something clattered and the car wouldn’t go. I found that a mechanic I had helping me had installed the propeller shaft but he hadn’t put a lock washer under the retaining nut. So of course, it had unscrewed itself and the shaft fell off.
The moral to that is: Never trust somebody else. Do it yourself.
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