exhaust gas temperatures

[dug]

Well, I finally installed my probe on the header for EGT. It was really hard taking a 1/4" bit up to that nice JP header and boring a hole in one of the runners, but once I had the pilot hole made, there was no turning back. Install was clean and easy ('42 Draft Designs' even includes shrink wrap for connections, sweet!), and for now I am opting for the band clamp attachment till I can actually take the header off and have the nice bung welded on, making it a super clean install. Probe is located about 1 1/2" behind the head on the no. 3 runner (I now realize I should've used the no. 4) almost on the beginning of the downward curve of the runner so I can use the existing hole in the heat shield once I get that put back on.I haven't had a chance to really take it out and run it (thats what the trip to Berkeley next weekend is for), but on a quick 10 mile jaunt around the neighborhood I was able to make a few observations:Idle at OT: ~700°FAccelerating (no, or low boost): ~1000-1100°FHwy Cruising at 80mph, steady: ~1200°FBoosting (5-7psi): This is very preliminary. I really need to get it out and just run it for a while, but the thermocouple provides almost instant response to temperature changes - very nice. And it looks like the water injection is doing what it's supposed to be doing. I really couldn't get it beyond 1300°F if I tried. >>>after driving it for a while now, I've noticed that until the water injection turns on at around 5psi, egt's continue to rise to about 1300°F, but doesn't ever get much hotter than 1350°F. However, if I fully boost to activate water injection, my temps actually go Down to about 1200°F. I'll keep this in mind on those long mountain ascents where I run the possibility of running too hot, and tell my girlfriend: "But I have to Boost, honey, otherwise my egt's get too hot."