To say it was an interesting day at the dyno would be an understatement. For about the first 2 hours everything went great... until the car started falling apart. I don't have the graphs for the day, having left pretty frustrated when we left, but it wasn't all bad. I'm going to try to have Arthur e-mail those to me.
By about noon Kevin had the car in really good form. It wasn't making a crapton more horsepower (117.? whp and 99.8 lb/ft), but kevin found significant gains in the midrange through adjusting the ECU timing advance.
We decided we were pretty much done and would let the car cool down to make an apples-to-apples power run as had been done with the last dyno (notice on the graph it gained 2-3 peak HP and 3-4 lb/ft). Similar gains would put us over 120 hp and 100 lb/ft, which was my goal. Well, that's when it all fell apart. An electrical issue was giving a very spotty signal from the temp sender that controls how the enrichments are handled. After managing to get the car started again (which was an effort), we did 1 last run that wasn't really worth much due to the sensor being out of whack.
Then as kevin pulled it off the dyno, the muffler fell off taking the tail end of the cat with it. You can see on the metal of the cat where it had been leaking for a while (about 50% of the way around the tubing) and it finally gave up the ghost today. And then back at Kevin's house, we were swapping the stock ECU back in (he's going to try to track down where the signal noise was coming from on the MS) and I was pulling the WBO2, kevin noticed that there was a crack 1 one of the runners of the header. Very hairline, but it wasn't there before. It probably came from having a ton of weight (header / cat) hanging off the back of the header without any support (the muffler has a hanger on it, but as we revealed previously, it had fallen off).
Summit Racing has a Magnaflow direct-fit cat for $108 or so that I can pick up in the middle of next week some time, and I've got an appointment w/ a fabricator friend to drop the header off on Tuesday to hopefully have everything back together by Friday / Saturday so the car can get aligned on Sat.
Of course that means I still need to pull the rear lower control arms, swap all the bushings over to the straight A arms and have the wheel bearings rebuilt. It's going to be a long week, but we're getting there. I'm extremely happy with the promise that the Megasquirt showed, and it proved that there were some pretty stout gains to be had by getting control over the fuel and timing in this car. If Kevin can get a couple kinks worked out, we're going to be looking fantastic
