LeMons 24 Hour CMP Sept. 2020
- FJCamper
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LeMons 24 Hour CMP Sept. 2020
I love endurance racing, especially 24-hour events. I've crewed in three Daytona's, getting a third place finish with Charlie Kemp (Porsche RSR) in 1975, and one 10th overall and one 1st overall win with Brumos Porsche (934 & 935)in 1977-78. Finally, LeMons gave us a chance to run a true 24 hour with the Blitzwagen, which is well sorted out and has been running 1st in class routinely in 2019 until something broke or we got hit. We could beat the competition, but not ourselves.
11Spt20; Fri.
After nearly a season off for COVID-19, the Blitzwagen is ready for action. Driver Jamie (aka Jamrod) and I (crew chief) arrive CMP just before dawn, first in line, and have to wait at the registration building until the gate is unlocked at 0700 EST. Once inside, we tow to garage bay 23, and find that drivers (and owners) Hawk and Dr Steve are just crawling out of their tents, and crew Justin Tela and his volunteer friend are also present. Jamie unloads the trailer -- the weather promising to be warm -- and Hawk gets to see the Blitzwagen in its new configuration. He likes it.
The Blitzwagen's body kit is homemade, just jig-sawed ABS plastic panels on strong braces. LeMons rules require that the original hood of the car be retained.
The body kit might not add to our aerodynamics, but it doesn't hurt them, either.
We track the Blitzwagen for test, to familiarize Hawk and Dr. Steve with the handling changes the new 19mm rear sway bar makes, and to bed in a new set of Wilwood (hard) enduro front brake pads. TP are still 26/28. The car is fast and smooth on the new 205/50R15 Nitto street radials. Hawk comments the car has ever run or handled as well. The 94x78 bore and stroke engine is under-cammed (Engle W125) to keep the RPM's at 6000 for endurance racing. On dual 34mm venturi Solex (Kadrons) and 160 main jets, we have torque to spare.
The race strategy is simple. We just make laps, we don't race. We have four drivers. Each one does an hour and a half, which is sometimes all we can do on our 12-gallon fuel cell. We have just three crew, including myself. Not a lot for a 24-hour race, but you race with what you have, not what you want. We're lucky there is even a race under the constraints of COVID-19.
The Blitzwagen's dash is all business, right down to the on-board fire system activator. The warning lights are big and bright, unless you do what we did to ourselves and unknowingly disable them.
As Hawk takes the Blitzwagen though tech, the starter button on the dash fails. Just plain embarrassingly dead. The racing gremlins have also had time off, and they're ready to rumble. As we replace the button, I worry a little about the reliability of the recently replaced main seal. It's already seeping onto the diaper we rigged in Birmingham.
Because of the pandemic, there is no downtown Camden block party this year. And no party at the track. Face masks are enforced. Most teams sit and drink in scattered groups, socially distanced. The evening weather is cool, ambient temps down from the Gulf coast hurricanes.
Driver David Scott arrives after dark, having driven up alone. We are ready.
David working on the Blitzwagen before the Saturday morning start. The strakes along the roof line prevent air from spilling off the edges, and channel it down the rear window to the wing deck and oil cooler windows.
12Spt20; Sat. 24HR CMP. The mid-morning weather is good, mild and partly sunny. Hour meter reads 236.2 That's car hours, not engine hours, since installation of the meter about September 2013. TP still 26-28. Dr. Steve takes first shift, joining the 94-car field late, trailing the pack, to save gas on the repetitive staging laps that typically occur while the transponders are pinged. The green flag goes down about 1000 hrs EST.
Within minutes, we hear on a worker's radio that Steve has been black flagged. Sure enough, we soon see him cruising by on the access road to the two story race control building and penalty impound. Hawk sprints from the garage bay after him. We are angry and confused, but the situation quickly sorts itself out.
Our transponder, a brand new MyLaps X2, has failed to hold a charge on its first race. The racing gremlins want us bad. Hawk quickly rents one from race control and Dr Steve roars back out into the fray. Steve fights his way up to 1st in class.
We've been running first in class early for the last few races. The Blitzwagen has come into its own. However, as Pogo once said (if you remember Walt Kelly) "We have met the enemy and he is us."
About 1230 hrs, a big heavy Volvo 4-door sedan that shares space at our end of the garage and a Mustang collide out on the track, flipping the Volvo into the air end over end where it lands on its roof. The Mustang is kaput. I'm concerned about the Volvo because the drivers are from Birmingham and normally run a new Beetle. We've helped them out.
Then we see Dr. Steve being towed in on a strap. What now? We swarm the car. Everything is dead. Battery, Instruments. There is significant damage to the front airdam, but not from impact. Turns out that Steve and the tow truck driver got their signals crossed and the truck was accelerating at a point when Steve was braking, and the strap lash almost pulled our reinforced FIA tow-hooked bumper clean off.
The airdam before the towing incident. You can see the yellow FIA-certified towhook. We never got to use our double row of LED lights.
Steve thought he had run out of gas, but we quickly discover that when we replaced the starter button (reaching behind the dash) somehow a wire connector or two had been knocked loose. Steve had been running on battery.
Our big red alternator warning light had not triggered, because it was one of the disconnected wires. David fixes it. We jump off 57, refuel, and at 1300 hrs, Hawk takes 57 out. The stop had cost our 1st in class lead. We're now third. Somewhere in this, we posted our best lap time of 2:12, certainly not our best lap time ever at CMP, but evidence of restraint. David once set a 2:04 here in the Blitzwagen. A dipstick check warns we are down a little in the 3-gallon oil sump.
Some exposition and a mea culpa. Last year here at CMP, on 14 September 2019, We threw a rod (failed rod bolt) which locked up the engine so suddenly the inertia in the flywheel actually broke one of the eight crankshaft dowels. We had the crank reground and the flywheel inspected for cracks. I decided to run it on seven dowels once we discovered the broken dowel could not be drilled out with the equipment we had, and that included a good vertical drill press and armor-piercing bits. But even with a new O-ring, attempting to reconnect the old crank and flywheel was going to prove not to work.
1445 hrs. Hawk exchanges the driver's seat with Jamrod. We still hold 3rd. 7-gallon 93-octane top-off. Oil temp has not exceeded 220° F. even in this now late Indian summer afternoon with our new dual 96-plate Mesa oil cooler system, plumbed in -10AN braided steel hose, fed by a common engine case top adaptor.
Jamrod picks up the pace, dicing through traffic, and within the next hour takes us back to 1st in class. Near the end of his stint, he begins to get oil warning lights in the corners. This worries Jamrod and he brings 57 off the track and into our garage bay.
A quick dipstick check on the dry sump tank reveals we are very low on oil. The main seal is leaking Lucas Hot Rod oil liberally. We can't keep feeding it. A command decision has to be made right now. "Pull the engine," I say. This is no small job, with the collision frame bolted around the engine and all the plumbing involved.
David, Jamie and Justin jump to it, tools in both hands, experts in what they do. 57's W125 cam engine is finally on the jack and Jamie has the flywheel off. This is where the geared Torque Meister tool is worth a fortune. Nothing is visibly wrong. O-ring in place, Main seal looks good. Flywheel hub mating surface to main seal feels smooth. Yet the assembly was pouring oil. Later, once this was all over, we would find there was some sideways bulging around the flywheel's dowel pin holes that kept the flywheel and crank from mating flat. The clock is ticking.
"Swap engines," I say. We know the backup engine, even with time on it, does not leak. It has an Engle W140 cam and is not a cruiser. By the time the backup engine is installed, the sun is not long for the sky. Fuel pump on, float bowls filled, starter pressed. The engine spins over and fires, backfires, and won't idle. "The carbs are dirty," I yell over the no-baffle stinger, "let it run!" The backup engine has been set aside for months. I know it'll clear up as the jets clear themselves, as the float pivots free up. These are simple single barrel Solexes. Big, but simple.
David kills the engine. "We need to swap carbs from the other engine" he says. Jamie and Justin agree. The clock is still ticking. "It'll clear up," I say. No one else agrees. I am crew chief but not a dictator. I have to respect the other experienced crew members. "Okay. Swap the carbs," I relent, and I get out of the way.
(from the Kadron Manual)
There is always a moment before disaster, such as just before the Titanic lookout saw the iceberg, or when Custer's scouts waved him the proceed signal. There are two very small machine screws that hold the throttle body to the carb. They tend to loosen, but can't fall out if a certain one of the manifold to throttle body gaskets are in place.
Jamrod disassembled the throttle body from the 3-4 cylinder side and in haste paid no attention to the gaskets. I'm on my stool beside the car when I hear someone say "Where's those screws? Did they go down the manifold?"
No one can find the screws on the concrete floor, they are too small. And its dark now, the garage florescents not near bright enough. Everything is reconnected. Time to race or start a new tear down. So, it's Russian Roulette. "Fire it up," I say. You pays your money and you takes your chance.
We lose. The engine starts with a mighty roar, and there is a visible flash of fire under the engine as cylinder three's cast iron barrel broke.
On disassembly back in Birmingham, we will see that both screws passed through the 40mm intake valve and were smashed together against the forged Mahle piston at it's lowest point, wedging into the Copperhead gasket, and cracked the cylinder. The piston crown was mashed down on its rings at the point of impact.
We're done, just seven and a half hours in, only 123 laps. During the night, several cars will catch fire, some collide, the timing and scoring and even PA system will fail for a while. I make it to my cot in the trailer, watching the headlights go by in the dark, listening to the engines, resting fitfully, Daytona flashbacks replaying in my mind. You go to sleep to the sound of engines and wake up to the sound of engines.
A LeMons veteran 1998 Kia Sephia takes C Class. Not because it was fast, but because it didn't break, wasn't hit, and over a long 24-hour race, just made laps.
- Clatter
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Re: LeMons 24 Hour CMP Sept. 2020
I love reading these..
Speedier than a Fasting Bullet!
Beginners' how-to Type 4 build thread ---> http://shoptalkforums.com/viewtopic.php?f=1&t=145853
Beginners' how-to Type 4 build thread ---> http://shoptalkforums.com/viewtopic.php?f=1&t=145853
- doc
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Re: LeMons 24 Hour CMP Sept. 2020
Great write up. Sad result. Fun to read.