DIY_EFI Digest Sunday, 21 April 1996 Volume 01 : Number 116 In this issue: TEC-II super B MAF bypass loop See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: Hoa T Nguyen Date: Wed, 17 Apr 1996 23:16:53 -0700 (PDT) Subject: TEC-II super B Re: Speed Density SFI -possible? I think the new TEC has the option of running TPS based at low RPM's instead of MAP or MAF for cars with big cams. Once the MAP gets stable the system will switch over for accuracy. It seems to be refered to as Super 'B' software. Mike Kent ------------------------------ From: TAR Date: Sat, 20 Apr 1996 20:45:19 -0600 (MDT) Subject: MAF bypass loop Hello gang! I was wondering if anyone has seen/tried this type of MAF setup... - -----------------------------------------\ from filter || MAF ---\ - ---> ------------------------\ ---\ - --\ \________________________\ ----------------- \ bypass line to engine ------> \_______________________________________________________________ (sorry about the poor quality ASCII art, obviously I'm no expert!) The MAF is represented by the two vertical bars in the top tube. My thought is this: the MAF is usually the most restrictive part of the induction system, and who says it needs to be the only path to the engine. I figure if you have a bypass tube sized so most of the flow doesn't see the MAF at all, you will drastically reduce delta P trough the intake tract. However, this is not without problems. I am not sure of the Reynold's number range an MAF is designed to operate (anybody?). In addition, I could see this type of setup reducing transient response of the overall system. Whadda ya think? does this have potential? Getting back to the Reynolds # range; no doubt an MAF is fairly accurate within a certain range and under specific conditions, how about below the lower limit and above the upper limit? does the sensor response become non-linear? is there even a response? will the sensor ouput curve flatten off? What are the conditions an MAF is expected to operate? laminar smooth, no turbulence? is there any rule of thumb re how far upstream you must keep a straight shot to the sensor? Any help you pros could give me would be greatly appreciated... Thanks gang. Todd- ||||||||||||||||||||||||||||||||||||||||||||| Todd Ratke e-mail: LPGV Engineer tratke@xxx.ca -or- ratke@xxx.ca ||||||||||||||||||||||||||||||||||||||||||||| ------------------------------ End of DIY_EFI Digest V1 #116 ***************************** To subscribe to DIY_EFI-Digest, send the command: subscribe diy_efi-digest in the body of a message to "Majordomo@xxx. A non-digest (direct mail) version of this list is also available; to subscribe to that instead, replace "diy_efi-digest" in the command above with "diy_efi".