turbo EGT rise, and wideband O2

[Todd King]

     <<<
     Corky Bell's new book published by Robert Bently called "Maximum 
     Boost"
     is all about turbos and their theory, installation and tuning. It is
     excellent. From there you will learn that normal turbine back pressure
     is 2-3 times manifold pressure but the lower the better to a certain
     point as pressure is necessary to extract the energy as you suggested.
     >>>
     
     So it's out finally- I asked Corky (of Bell Engineering in San 
     Antonio- I'm from there too; formerly Cartech in Dallas, which was 
     formerly associated with Haltech, which is now in Australia or similar 
     I believe... get me- quite the name-dropper!:-) a few months back but 
     it was not yet out. I'll check it out! I've seen some interesting data 
     from the Engine Analyzer SW on backpressure with turbo; I think the 
     exh man press is typically a bit higher than the pressure on the 
     intake side, or thereabouts.
     
     
     <<<
     I found in my own turbo car that had a pretty restrictive cat and 
     exhaust,
     that I had very high temps (1650 deg F) until I lowered the pressure
     after the turbo.    >>>
     
     I have a 3" mandrel bent downpipe from the turbo, which is run open at 
     the track; no backpressure problem here! :-)
     
     <<<
     > >Also Frank, any way you could put a copy of that graph on the DIY 
     web site
     > >so all of us could get a look at it.
     >
     Yes, I will do this as soon as I can buy a good 24 bit or better color
     scanner that will work with my Gateway 166 MMX portable.   >>>
     
     I'll scan it here at work if you'll send me a copy of it; or you can 
     just truck on over to your nearest Kinko's for the same result...
        BTW I hit up the company employee resource center recently for 
     everything they had from the SAE- turned up lots of very intereasting 
     stuff, all currently stacked on my desk (you want it when??? 
     Haw-haw-haw...) Wouldn't you know it- several papers on wideband O2, 
     like #890299: "Wide-Range A/F Sensor", or even better, #880559: "A 
     Portable Fast Response A/F Ratio Meter Using an Extended Range Oxygen 
     Sensor" by Nissan engineers. And you were wondering how all these 
     automotive "garages" were suddenly coming up with these engineering 
     "design feats" to bring out their new wonder A/F meters? :-) These 
     papers are dated from the late 80's... Oh, and I can't resist one 
     that'll make the list collectively cringe- #910259: "A PC Engine 
     Control Development System"... remember that thread <*shiver*>?
     
     Todd       tking at scic.intel.com