Car Prep for SCCA PDX at Summit Point Circuit
Well, it was a mixed bag of a weekend, and entirely exhausting for me. I was so tired at times that I questioned whether it was worth it or not, certainly on Sunday afternoon when it had started raining before our third of four sessions.
On Friday night I got the oil changed, brake fluid flushed, car loaded with wheels, tools, helmet, jack, chairs, fluids, and cameras. By then it was about 9:30, and I'd be leaving for the track at 5:30am. I was tired already, but I actually got some sleep.
Overheating due to more cylinders in play?
At the track, we had dry sessions on Saturday, and the car was running well, but after the first session I noticed a puddle of coolant forming under the car. It had spilled out of the overflow tank's vent hose. This had never happened before, but when I parked it after the session, I guess latent heat in the block boiled the coolant to push a bunch of fluid out. From then on I made sure to do a couple laps around the paddock to cool it down sufficiently before parking it.
Near the end of my second session on Saturday, I heard my engine suddenly sound REALLY loud, coupled with a clanking, grinding noise. I was just past pit-in, so I had to drag something all the way around the track again before I could pit in and investigate.
To orient you to what happened, my car's exhaust goes like this:
engine -> header -> welded flanges with gasket -> test pipe -> flared flanges with ring -> resonator/tailpipe/muffler assembly
The test pipe had broken at its connection with the flared flange, and the rubber hanger that might have held it up broke as well, allowing the resonator to drop to the track and drag for two miles. What you see is the broken end of the test pipe and the beating that the resonator took on its trip around the track.
Fixing the Exhaust
I could have driven without a muffler, but I was afraid the test pipe or something else would fall off too. So I threw the muffler in the back and headed home to try to do something about it.
I was under the impression that the exhaust was 2.5" forward of the muffler. But the test pipe is actually 3" until the very back end, and it reduces to 2.5 where it connects to the resonator. So the 2.5" extensions I bought on the way home from the track weren't ideal. What WAS ideal was all the 3" tubing I had at home, and the two flanges and a gasket I had purchased for my muffler project but didn't use.
So Saturday evening I quickly fabricated a replacement test pipe that bolted right in where the old one was, and it was perfect. I'm even getting better at TIG welding, and when I get my foot pedal wired up, I hope to get good enough that I don't need to pour so much heat into the work.
Exhaust Hanger Fix
Another thing that worked out nicely was that when I returned my unused exhaust pieces to the parts store that evening, I picked up a universal hanger isolator which I modified for my use.
After cutting the rubber between the upper slot and the two holes, it made the perfect replacement for $5, rather than waiting a week for a $20 OEM one.
Terrible Noise?!?!
I got all this done and bolted in by about 10:30 pm. When I fired up the car to hear it, I also noticed a horrible flapping noise coming from the distributor area. I decided I'd address that in the morning after some sleep, albeit an hour less of it due to daylight saving time.
Besides that, the exhaust still sounds like poo. I feel like there's something in that resonator that's rattling around, and/or the header has holes in it as well. I'll have to do a thorough assessment of the header's integrity, and I will soon replace the remaining old resonator+tailpipe portion with all-3" stainless tubing.
Sunday - Fixing the Serious-Sounding Noise
Sunday morning I got up at 5:30 and started looking for that noise near the distributor. I took off the cap, and finding nothing wrong, I went into the area of the timing belt cover, since that was what I had last messed with.
Then I took off the belly pan, and looking up, I found the problem, and it was what I had LAST LAST messed with: while changing my oil, I had jammed a piece of plastic jug under the oil filter to divert spilled oil away from the power steering unit and pulley. It worked like a dream. But I had simply forgotten to remove it, and it had ridden there all day Saturday. I just couldn't hear it over the noisy exhaust, I guess. It was flapping against the power steering pulley, making a racket. I pulled that out of there. Problem Solved.
I also re-tensioned the timing belt while I had that cover off, and headed to the track.
Sunday - On the Track
I joined the first session just a minute or so in, and I was just feeling better because a lot of these little bugs had been worked out. It was also good to get some decent dry laps in. Advanced group is nice because everyone is fairly predictable, and there weren't many trains to deal with because passing is allowed anywhere with a point-by. Intermediate group could be annoying that way.
The car is about 2 seconds faster around the track (1:32's vs 1:34's) that it was before the valve spring fix. It's still slow. But it's nice to know I'm getting all the power it has to give.
Don't Drive Tired
It rained starting the third session on Sunday. It was wet, it took all my concentration, and it just felt like work. Not thrilling, just taxing. I put down too much power coming through Turn 2 and got completely sideways. I actually ended up touching the inside tire wall with my bumper after sliding sideways across the wet grass for what seemed like a hundred yards.
Fortunately there was no damage, and nobody saw me do it. There were so few cars left that nobody even passed me while I restarted the car and rejoined the track. I dutifully came in to talk to the marshall, and went back out for three more laps before coming in and calling it a day.
I honestly think that if I weren't so tired, I would have been able to make the necessary corrections much earlier, avoiding any close calls at all. So I skipped the last session and mustered enough energy to pack the car, drive home, and unpack the car.
So, all in all, I gained lots of experience this weekend, but I really want to spend more time driving and thinking about driving, and less time wrenching and worrying about the car. That'll certainly have to happen before June, when this car is going to have to take me through competition school (NASA @ the new Dominion Raceway).