So, I knew academically how altitude affected power levels due to the less dense air, but it was hard to imagine that people could REALLY lose as much power as I was being told. So, I moved up in February from the DC area (5000' higher), and immediately dyno'd to see the comparison. My peak number losses were 45whp/36wtq. However, my WHP peaked way earlier around 5300rpm instead of well above 6000rpm. The downside of this is that although I only lost 45whp peak (only? hah), my WHP lines diverged above 5500rpm meaning my WHP loss up above 6000rpm was as much as 60 .
Well, as soon as the first track opened in Pueblo, I was unable to go, since my ACT HDSS went out after some road racing. I got an Exedy 4-puck (single cerametallic), slapped it in, then went to the next test'n'tune up in Denver at Bandimere. I documented those runs along with a vid previously. The best run was a meager [email protected]
with a shift to 5th way back at the 1000' mark due to the aforementioned power drop after 5500rpm, and with only a 1.75 60' on Blizzaks. Not as bad as some people guessed, but obviously not as good as _I_ was hoping.
So, today I took another trip up to Bandimere with the same mods and power levels, but with some new 255-width Azeni RT615s. They were much sticker and didn't spin all through 1st like the Blizzaks, and they did so with a full 28-30psi as opposed to the 20-22psi on the Blizzaks. So, I wasn't spinning much and wasn't bogging, but still was only seeing 1.75 60s with more 12.4-12.5s and the same 107-109mph traps. Since this wasn't a test'n'tune, but rather a big American Muscle race day (all bracket), I got 3 test runs, but then had to start competing. I lucked out in round one as my opponent ran his best ever and accidentally broke out. I was on my way to my best run according to my 1/8th mile, but I missed 5th while paying too much attention to the Vette I was running down from behind. Since he screwed up, I got to go again, but my point was to get a good time, not try to win a big bracket race.
Ok, so my best run by this point at this altitude was a 12.45, but my 1/8th indicated a high 12.3x if I didn't miss 5th, so I dialed in at 12.38 with the hopes of being able to hit a 12.3x and still win without breaking out. However, I had already made up my mind that if I were to blow past my opponent from behind, I would not hit the brakes just to win, but rather keep the gas floored in order to get the best ET possible. The result was this:
12.30 at Bandimere
I ran him down and blew past him due to a much better reaction time, and the fact that I blew past my dial-in time. I went from a 12.45 to a 12.30 with only a .03 improvement in 60' and no increase in MPH. In fact, my MPH was slower, but I'm not sure why. I think maybe I let off early? Can't tell from the vid, though. Since this was just a 1.72 60', I'm still not yet satisfied. Today was the first time using the 2-step on tires that actually grip, so hopefully I can start nailing mid 1.6s after some more practice. I steadily improved each launch today, so with a 1.6, I may squeeze out a solid 12.2. If I can do that, then I can feel good about overcoming the altitude as well as can be expected. Now I need to find out what the fastest stock turbo Evo time is up here at nearly 6000'.
My best slip and my first slip, which has inexplicable numbers. I have no idea what happened, but it didn't happen again. I do think the ET vs MPH on both of these help to illustrate exactly how quick I'm able to shift now with the Exedy 4-puck.