DIY_EFI Digest Friday, 1 March 1996 Volume 01 : Number 061 In this issue: Re:Ducted Fan Engine Re:Ducted Fan Engine Re: Hi-resolution Crank angle sensor Re: Hi-resolution Crank angle sensor Re: Hi-resolution Crank angle sensor Re: Injector driver chips? Where? Re: FW: re: Re: spark and MAP Re: Turbo Lag Re: FW: re: Re: spark and MAP RE: Microsoft exchange & bloated attachments RE: New EFI reference Re:Ducted Fan Engine Re: Intake Runner? Totally tubular, man Re:Ducted Fan Engine Just a few GM TPI Questions Re: Hi-resolution Crank angle sensor Re: Totally tubular, man LO VS. HI RE: Hi-resolution Crank angle sensor Re:Ducted Fan Engine See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: "Hans Hintermaier" Date: Thu, 29 Feb 1996 13:56:52 MET Subject: Re:Ducted Fan Engine Cliff Ducharme wrote: >As far as using a ducted fan engine is concerned, forget it! These >engines run 15% - 25% nitro content alcohol-based fuel at 2-3 ounces >per minute consume glow plugs (one per ten minute flight), have a >nasty habit of flaming out, and >if not carefully cleaned up after each session, develop rust deposits >in their crankshaft bearings that often lead to catestrophic engine failure. If you reduce compression and fit a spark-ignition-system, you can use normal-gas without nitro and therefore won't have any corrosion inside the housing. A model-engine normally is very reliable for years (exept race-engines which sometimes make more than 32000 RPM!) But I would also prefer electrical motors.. Hans hiha@xxx.de ------------------------------ From: "Hans Hintermaier" Date: Thu, 29 Feb 1996 13:56:52 MET Subject: Re:Ducted Fan Engine Cliff Ducharme wrote: >As far as using a ducted fan engine is concerned, forget it! These >engines run 15% - 25% nitro content alcohol-based fuel at 2-3 ounces >per minute consume glow plugs (one per ten minute flight), have a >nasty habit of flaming out, and >if not carefully cleaned up after each session, develop rust deposits >in their crankshaft bearings that often lead to catestrophic engine failure. If you reduce compression and fit a spark-ignition-system, you can use normal-gas without nitro and therefore won't have any corrosion inside the housing. A model-engine normally is very reliable for years (exept race-engines which sometimes make more than 32000 RPM!) But I would also prefer electrical motors.. Hans hiha@xxx.de ------------------------------ From: pjwales@xxx.net (Peter Wales) Date: Thu, 29 Feb 1996 09:35:45 -0500 Subject: Re: Hi-resolution Crank angle sensor >>>Not necessary. Add one sensor instead. >>> >>> >>> * x >>> _ _ _ _ _ _ >>>_/ \_/ \_/ \_/ \_/ \_/ \_ >> >> >>This doesn't make sense. For every peak there will be a trough and each >>sensor will detect the same thing. >think about which sensor fires when - they are (hopefully) >180 deg out of phase -> like having twice as many teeth >twice as close >Matt Smith >masmith089@xxx.com >Mailer Eudora 1.5.2 I can't go with that Matt, I can detect that there is a trough by not having a peak at sensor 1 so I don't need sensor 2 to tell me. However, see Darryls posting which explains it to me better. You need 90 degrees phase dfference not 180 which the pic shows and that's what fooled me. Peter Wales President Superchips Inc Chairman Superchips Ltd "Timing is everything" Superchips home page with all the answers http://www.superchips.com ------------------------------ From: pjwales@xxx.net (Peter Wales) Date: Thu, 29 Feb 1996 09:42:48 -0500 Subject: Re: Hi-resolution Crank angle sensor > > >> >Not necessary. Add one sensor instead. >> > >> > >> > * x >> > _ _ _ _ _ _ >> >_/ \_/ \_/ \_/ \_/ \_/ \_ > >Peter Wales wrote: > >> This doesn't make sense. For every peak there will be a trough and each >> sensor will detect the same thing. > >Ah, but the key is in the phase difference between the two sensors. This >will only work if the tooth is asymmetrical, ie the peak is much narrower >than the trough. Assuming that this is the case, sensor waveforms will >appear like this: > _ _ _ _ >Sensor A _____| |_____| |_____| |_____| |_____ > _ _ _ _ _ >Sensor B _| |_____| |_____| |_____| |_____| |__ > _ _ _ _ _ _ _ _ _ > A + B _| |_| |_| |_| |_| |_| |_| |_| |_| |__ (logical OR of the two) > >Voila, double the output frequency. Ah ha, now I see it. However, getting an asymettrically toothed flywheel won't be easy. Would this still work if the pickup was moved away from the tooth to make only the peak of the tooth effective, thus changing the m/s ratio artificially. As a matter of interest the Nissan 300 ZX Twin Turbo distributor has 2 sensors in it. One reads crank angle from the 360 lines on the disc and the other reads an encoded cylinder number from the 3 digit code. Japanese engineering! Peter Wales President Superchips Inc Chairman Superchips Ltd "Timing is everything" Superchips home page with all the answers http://www.superchips.com ------------------------------ From: pjwales@xxx.net (Peter Wales) Date: Thu, 29 Feb 1996 09:56:39 -0500 Subject: Re: Hi-resolution Crank angle sensor >At 06:06 PM 2/28/96 -0500, you wrote: >>>>Yes, if you can get a 200 tooth wheel. >>> >>>Not necessary. Add one sensor instead. >>> >>> >>> * x >>> _ _ _ _ _ _ >>>_/ \_/ \_/ \_/ \_/ \_/ \_ >> >> >>This doesn't make sense. For every peak there will be a trough and each >>sensor will detect the same thing. >think about which sensor fires when - they are (hopefully) >180 deg out of phase -> like having twice as many teeth >twice as close >Matt Smith I must stop thinking at this time of the morning, I get confused! Yes, I can see this now, hopefully this will get read before I get 500 messages axplaining it to me. I need a cup of tea:) Peter Wales President Superchips Inc Chairman Superchips Ltd "Timing is everything" Superchips home page with all the answers http://www.superchips.com ------------------------------ From: MSargent@xxx. Sargent) Date: Thu, 29 Feb 1996 10:52:52 -0500 Subject: Re: Injector driver chips? Where? Regarding the Adobe PDF viewer: They (Adobe) released a new version of AcroWeb within the last week. If you have the earlier version (December 95 I think) you should get the updated version. I had problems with the old version crashing on some valid PDF files, and the new version was able to read them, just fine. Mike +--------------------------------------------------------------------------+ | Michael F. Sargent | Net: msargent@xxx.com | Phone: 1(613)721-0902 | | Gallium Software Inc.| | FAX: 1(613)721-1278 | +--------------------------------------------------------------------------+ ------------------------------ From: MSargent@xxx. Sargent) Date: Thu, 29 Feb 1996 10:55:49 -0500 Subject: Re: FW: re: Re: spark and MAP > in order that combustion be finished at the the desired crank location. Correct me if I'm wrong, but I thought the advance was to deliver the peak cylinder pressure at the correct time (about 15 degrees ATDC in most engines). When the burn starts, or ends is secondary. You don't want peak pressure too early, or you lose power, or even knock, and if it comes too late then you've wasted power. Mike +--------------------------------------------------------------------------+ | Michael F. Sargent | Net: msargent@xxx.com | Phone: 1(613)721-0902 | | Gallium Software Inc.| | FAX: 1(613)721-1278 | +--------------------------------------------------------------------------+ ------------------------------ From: sian@xxx.uk (RAGHBIR SIAN) Date: Thu, 29 Feb 1996 17:48:52 GMT Subject: Re: Turbo Lag >Hello all, > >An idea which we have been discussing is injecting fuel into the exhaust >manifold during periods of closed throttle in order to keep the turbine speed up >and reduce turbo lag. >Has anyone tried something like this? Would the burning fuel damage the >turbine blades? What type of injector would be suitable? (maybe a Diesel >injector.) > >All ideas appreciated! >Chris Howard >What you are looking for is called an Anti-Lag System (ALS). It is >used in many rally-race cars that compete in the WRC. >This system actually causes an intentional mis-fire by not firing one >of the cylinders. The air/fuel mixture is still injected, and ends up >getting pumped out the exhaust. >The system is currently used on several Rally cars in the US. It is >supposed to keep the boost always running atleast 10-12 lbs. >The biggest draw backs to this are the noise and the flames that shoot >out the exhaust. (I wonder how a Catalytic converter would react to >this.) Hi Chris, I have worked on Anti lag systems (Um-Luft for Germans) for quite a while (about 4 Years). Most of what people have said is partially correct hence i have decided to reinforce what they have said and also clarify the issue. ANTI LAG. What you basically do is as soon as you come of the throttle pedal and the ECU senses the throttle is shut you retard the ignition timing to about 30 degrees after TDC YES that is correct and at the same time dump some fuel and also open the idle speed valve to fully open(You cannot burn fuel without air (somebody is going to try and prove me wrong)). This does two things lets the fuel and air into the cylinder (remember the amount of air in a cylinder is quite small during periods of shut throttle) which carry on combusting until after the exhaust valve is opened, and any residual fuel shall burn close to the turbine, hence increasing its speed and hence the boost pressure at shut throttles. You can only do this for periods of no more than 5 seconds because the pumping losses of the engine become fairly high and the advantage of anti lag becomes somewhat of a disadvantage. We have used air and fuel injectors in the exhaust and also elecris motors with a centrifugal clutch which disables the shaft at a predetermined speed hence freeing the wheel to spin with the exhaust gases. Clint mentioned Ford motorsport in the U.K used an ALS system. well all i can say about that is they were very late in introducing the system and secondly did not have a clue of how to implement the control hence the spitting of turbo charger turbines through the exhaust. I hope this helps. If you have any more questions please mail me direct as i think would be cluttering up the bandwidth. I would be happy to carry on if nobody minds. ciao R.S.Sian >>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<< Raghbir Sian Engine Control and Combustion Analyst "As Always A ***CONTROL*** Freak" A committee is a group of the unwilling, chosen from the unfit, to do the unnecessary.... Anonymous Life is just one damned thing after another... Joseph Heller Time spent on any item of the agenda will be in inverse proportion to the sum involved. E-mail: sian@xxx.uk >>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<< ------------------------------ From: ehernan3@xxx.com (Edward Hernandez (R)) Date: Thu, 29 Feb 1996 14:15:04 +0500 Subject: Re: FW: re: Re: spark and MAP "Correct me if I'm wrong, but I thought the advance was to deliver the peak cylinder pressure at the correct time (about 15 degrees ATDC in most engines). When the burn starts, or ends is secondary." This is correct, although I can't vouch for the 15 degrees ATDC. Start or end of burn is entirely secondary. ------------------------------ From: Jim Pearl Date: Thu, 29 Feb 1996 12:37:16 -0600 Subject: RE: Microsoft exchange & bloated attachments Gee Doug - I wonder who that person was? (ahem). Yep - I think it's me guys and I THINK I've got it fixed! Please tell me this is so! As for OFF by default - I don't think it was. Either that or while fumbling around trying to set up this client I turned it ON. It's now OFF and I'm hoping it's all better. I'll tell ya' this I don't much like Exchange and if this is their response to Notes they're in trouble! P.S. Thanks to Brad for what I believe is the solution and to Doug for alerting me OFFLINE and working with me on this. If anyone has any follow up comments on this "problem" please take them up with me OFF-LINE so as to keep the "noise" down... TIA! - ---------- >From: Doug Rorem[SMTP:rorem@xxx.edu] Sent: Wednesday, February 28, 1996 2:09 PM To: diy_efi@xxx.edu Subject: RE: Microsoft exchange & bloated attachments >---------- >>From: Brad Martin[SMTP:btm@xxx.net] >>Sent: Wednesday, February 28, 1996 4:16 AM >>To: diy_efi@xxx.edu >>Subject: RE: Blow off valve >> =SNIP= >It's usually a good idea to uncheck this box for Internet mail addresses >unless the sender knows that the receiver uses the Exchange client. > >--Kent I had worked with someone on this problem (we use Sun workstations here and are thankfully immune from generating this stuff). When they first turned off RTF (rich text formatting) they got rid of the MIME encoded attachment : Content-Type: application/ms-tnef Content-Transfer-Encoding: base64 eJ8+IiQEAQaQCAAEAAAAAAABAAEAAQeQBgAIAAAA5AQAAAAAAADoAAENgAQAAgAAAAIAAgAB BJAG AGQBAAABAAAADAAAAAMAADADAAAACwAPDgAAAAACAf8PAQAAAGMAAAAAAAAAgSsfpL6jEBmd bgDd AQ9UAgAAAABkaXlfZWZpQGNvdWxvbWIuZW5nLm9oaW8tc3RhdGUuZWR1AFNNVFAAZGl5X2Vm aUBj ....... but then their mailer started uuencoding the WINMAIL.DAT attachment. begin 600 WINMAIL.DAT M>)\^(CH"`0:0" `$```````!``$``0>0!@`(````Y 0```````#H``$-@ 0` ..... I certainly hope Microsoft has this stuff OFF by default. I guess there should be a FAQ in every list on the net as to how to turn it completely off. It creates large attachments which really have no utility on Internet mailing lists (i.e. who cares if their 3 line message is formatted with fancy fonts?) It certainly creates a lot of needless extra overhead when you figure that stuff is being sent out to every subscriber on the list. ==SNIP== begin 600 WINMAIL.DAT M>)\^(C,3`0:0" `$```````!``$``0>0!@`(````Y 0```````#H``$-@ 0` M`@````(``@`!!) &`&0!```!````# ````,``# #````"P`/#@`````"`?\/ M`0```&,`````````@2L?I+ZC$!F=;@#=`0]4`@````!D:7E?969I0&-O=6QO M;6(N96YG+F]H:6\M``,P`0`` M`",```!D:7E?969I0&-O=6QO;6(N96YG+F]H:6\M5]E9FE 8V]U;&]M8BYE;F`' ``0```"T```!2 M13H@36EC`!X,`0`` M``4```!33510`````!X`'PP!````# ```$I64$!14TDN0T]-``,`!A!CYNDZ M`P`'$$X'```>``@0`0```&4```!'145$3U5'+4E73TY$15)72$]42$%44$52 M4T].5T%3/RA!2$5-*5E%4"U)5$A)3DM)5%--14=565-!3D1)5$A)3DM)5D5' M3U1)5$9)6$5$4$Q%05-%5$5,3$U%5$A)4TE34T]!``````(!"1 !````U@<` M`-('```;#0``3%I&=7FMHH__``H!#P(5`J@%ZP*#`% "\@D"`&-H"L!S970R M-P8`!L,"@S(#Q0(`<')"<1'B<&AO('01@ 5 < T$D',"(!YP87,_( @H86@3X"DN M(%D<97 >,Q\P"X!K(&F,="<$( > (&=U$[ *( !P9!Y15$A)3M)+'E G=B(! M;P5 (: 0(&9I> F (2!0W&QE( `=T!/0; ,@(?%O(4$$("5Q'[ A"H4*A4$' M!" 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N, F _X%SDM$Z$"IP@[$@8(?R MD"+]0.!U(^$B((STAM:\='ZR_S6@*W&"`2IAK>(?$,!$?+#^8@3R,3"1P<$$ MP**L[7C?_WGA>@1Z7WML:&_:7PJ%%_$"`-Z@```#`! 0``````,`$1 ````` M0 `',&"X5&[4!KL!0 `(,&"X5&[4!KL!'@`]``$````%````4D4Z( `````( !+0`' ` end ------------------------------ From: Jim Pearl Date: Thu, 29 Feb 1996 13:16:39 -0600 Subject: RE: New EFI reference Another good one - Fuel Injection - Installation, Performance Tuning, Modifications By Jeff Hartman from Motorbooks International's Powerpro Series. Covers DFI, Electromotive, OEM, general theory, and is a decent book published recently (1993). ISBN 0-87938-743-2 - ---------- >From: Jerry Wills[SMTP:jwills@xxx.EDU] Sent: Wednesday, February 28, 1996 5:30 PM To: diy_efi@xxx.edu Subject: Re: New EFI reference Probst, C.O., "How to Understand, Service and Modify Ford Fuel Injection and Electronic Engine Control", Robert Bentley, Cambridge, MA, ISBN 0-8376-0301-3, 1993. Covers basic engine control theory and Ford systems to 1988. Excellent book on topic. Similar to author's other work on Bosch systems. Available from SAE for $30 (order B-584) - ----------------------------------------------------------------------- This is a good book for Ford people, but it is for 1988 to current ^^^^^^^^^^^^^^^^ 1993 was the publish date and it has a SVO part # M-1832-Z1 enjoy, Jerry Wills I'll have enough POWER when I can spin the tires at the end of the straight! 89 FJ DERSLYR, DoD#500 KotF(Flag) Mark Donahue, about 917's USC/Information Sciences Institute (USC/ISI) SoCal (310) 822-1511 x 236 90's cowboys, ride iron horses, and punch Deer!!! You done violated Physics, BOY! Assume the position..... (Rider 5/92) begin 600 WINMAIL.DAT M>)\^(CD3`0:0" `$```````!``$``0>0!@`(````Y 0```````#H``$-@ 0` M`@````(``@`!!) &`&0!```!````# ````,``# #````"P`/#@`````"`?\/ M`0```&,`````````@2L?I+ZC$!F=;@#=`0]4`@````!D:7E?969I0&-O=6QO M;6(N96YG+F]H:6\M``,P`0`` M`",```!D:7E?969I0&-O=6QO;6(N96YG+F]H:6\M5]E9FE 8V]U;&]M8BYE;F# $````% M````4TU44 `````>`!\,`0````P```!*5E! 45-)+D-/30`#``80=!TX9@,` M!Q!&! ``'@xxx.2D5#5$E/ M3BU)3E-404Q,051)3TXL4$521D]234%.0T5454Y)3DL"@P!0`O()`@!C: K H%1U`P`;T""P3=,$< :0:6,@8W,*A0J%D$)Y($H-P2!("L!N M= ."`U(B`70%L ;@;WYK!" ?,!/0!* @8P= )[$$(%!O=P20$U!O!E-I!Y N M( A0=@20!"!$Y$9)(+!%;!]A`V$=T$9I)_ @L$]%32"P9[<)\ 20!T @'>$% ML'D@xxx.\`8 L8T"N";"/0*#$Y M.00S*2>P25-"3B 0,"TX-RV ."TW<#0S+3(B[ KT+% Q!#@P`M%I+3$T-,\- M\ S0,-,+63$V"J #8/\3T!]P'K R]PJ',:L,,#)V>D8#83HS_C)V#((CX7() M*I @xxx.#% @2W022Y%1%5=,Y_?-*T&8 (P-=\VZU<) M@xxx._\V MZR(P>5]I#-C%W%%$+\C)V4 -@8D,3 MP""P0RY/+B"P(NY()M J0"H"K2(A/](]!& M!; >8![B"H4?."K2^RB5`P!C*( ;T N 'J (4+,", -@;"(@L @`8@20E05 M0BSR92JA0V$&T,T%$&0IT"'Q02Q2MBWE$#,W-BT<`# Q+7(S/S,S+@J%6@`G MU6+^80"05)!%$53B!:!50RI%>RK#4B-S$[,$(% !+6 X\CA9F$5X(6 @0"N7 M'Z'])3!P(F GL 8`!W #$ K!>5 !874=X 6P)I$=U'?3!;!?4T)O!/!H6:=< M]?E?\4%V"W +8 )@xxx.#0IOPJ%,OAG M3VA?:6\R_U1%8+\$("L3'C,KTV3R4B-P*G#["U I46)@X"L`;@$$(&3R^UVB M3_)C"'!+@05 "H8WH"U A8,Y0(,!4V\S5L #("@S M&_"#`#@xxx.P_R"P5P$>H'WP'Z%A M`1&PBS$O*M(L("%0=.!$">!R(?N-8 J%60A@*U >@E$@!O!S1<$>8%!H$[ B M8(LQ0JA/62%R`D$$$'4'@xxx.+<07 -2\Y,F8V2]\O M3.]-_ J%%_$`EJ ```,`$! ``````P`1$ ````! ``0!T'%]H&NP$>`#T``0````4```!213H@`````$8* ` end ------------------------------ From: jsturs@xxx.nl (Jim Sturcbecher) Date: Thu, 29 Feb 1996 22:30:13 -0100 Subject: Re:Ducted Fan Engine >>As far as using a ducted fan engine is concerned, forget it! These >>engines run 15% - 25% nitro content alcohol-based fuel at 2-3 ounces >>per minute consume glow plugs (one per ten minute flight), have a >>nasty habit of flaming out, and >>if not carefully cleaned up after each session, develop rust deposits >>in their crankshaft bearings that often lead to catestrophic engine failure. > >If you reduce compression and fit a spark-ignition-system, you can >use normal-gas without nitro and therefore won't have any corrosion >inside the housing. >A model-engine normally is very reliable for years (exept >race-engines which sometimes make more than 32000 RPM!) >But I would also prefer electrical motors.. > Are we talking about model "glo" motors or the new generation of model gas turbines that run at aroun 115000 rpm and have their own computer control system. These babies can put out 5Kg+ of thrust. Now maybe here is the front-end of a turbo system? Only drawbak is they cost around $3000+ :-( Later, Jim Sturcbecher jsturs@xxx.nl ------------------------------ From: ehernan3@xxx.com (Edward Hernandez (R)) Date: Thu, 29 Feb 1996 17:18:40 +0500 Subject: Re: Intake Runner? Snipped from a private post: "You stated that the "runner" formula quoted will only work on 4 cylinders or less . Could you explain why ?Surely if the the lenght is measured from the plenim to the cylinder it would not matter how many cylinders their are , as the sonic waves would only see the one cylinder from the plenim down , or does all this "ram effect" take place in the plenim itself ? Taking a close look at the formula, you will find a volume that is represented by, in the case of a four cylinder, the other three cylinders that are not breathing. The more cylinders you have, the more volume you have, and this volume affects the output of the formula. I have personally tested this formula on V6s and compared the results against more sophisticated modelling software and dynamometer data. For V6s, the formula is very inaccurate. Furthermore, modern V6s have a variety of tuning devices in the plenum with valves and tubes. The one I am working on has two of each. This represents additional volume and even if you include this in the formula, the results have turned out inaccurate. The ASME paper warns against applying the formula to engines of more than four cylinders, and my work confirms this. ------------------------------ From: Dan Bocek Date: Thu, 29 Feb 1996 15:04:19 -0800 Subject: Totally tubular, man Where can I find mandrel bent "U" shaped aluminum and steel tubing for fabricating intake and exhaust plumbing? Dan Bocek dan@xxx.com ------------------------------ From: "Kenneth C. King" Date: Thu, 29 Feb 1996 17:24:08 -0600 (CST) Subject: Re:Ducted Fan Engine [ munch ] > >If you reduce compression and fit a spark-ignition-system, you can > >use normal-gas without nitro and therefore won't have any corrosion > >inside the housing. > >A model-engine normally is very reliable for years (exept > >race-engines which sometimes make more than 32000 RPM!) > >But I would also prefer electrical motors.. greetings: what about the super-cheep smog-pump-as-a-blower? i.ve heard of these things making a few pounds of boost and they're motor speed driven... what are the drawbacks? any clues? later, kc ------------------------------ From: "George M. Dailey" Date: Thu, 29 Feb 1996 20:51:49 -0600 Subject: Just a few GM TPI Questions FYI, my '58 chevy likes the '89 5.7L TPI engine. Performance is very good. Should there be a very slight detection of detonation (knock) at idle with engine hot? What about slightly moderate knock at full throttle going say...70mph? NO code 42, or other est codes are present, 42 will set when 'set timing' connector is disconnected. Has any one noticed bad idle quality when the air cleaner is not installed (MAF was connected)? The problem seems to have 'fixed' itself after instaling the air cleaner and one of the missing PVC hoses. Could fine dirt affect a hot wire MAF? Thanks, GMD ------------------------------ From: dn Date: Thu, 29 Feb 96 20:01:06 MDT Subject: Re: Hi-resolution Crank angle sensor Peter Wales wrote: > Ah ha, now I see it. However, getting an asymetrically toothed flywheel > won't be easy. Would this still work if the pickup was moved away from the > tooth to make only the peak of the tooth effective, thus changing the m/s > ratio artificially. In a nutshell, yes. The distance from the sensor to the tooth will have a dramatic effect on how much of the tooth's width the sensor "sees". This adjustment could, in fact, be made either mechanically or electronically. > As a matter of interest the Nissan 300 ZX Twin Turbo distributor has 2 > sensors in it. One reads crank angle from the 360 lines on the disc and the > other reads an encoded cylinder number from the 3 digit code. Japanese > engineering! I was actually surprised that no one was doing this. (until now, that is) This is a combination of a relative position sensor (the 360 lines) and an absolute position sensor (the 3 digit coded portion of the wheel) There are many examples of commercially available encoders of both types, but to my knowledge there is no combination of the 2 used in industrial position sensing. For a DIS type system, should be easy to substitute an optical encoder for the guts of the distributor and get any timing accuracy you want. Optical encoders are notoriously fragile, however, and you may have a hard time finding one that will live a long and fruitful life in the underhood environment... - -- - --------------------------------------------------------------------- Darrell A. Norquay Internet: dn@xxx.ca Datalog Technology Inc. Bang: calgary!debug!dlogtech!darrell Calgary, Alberta, Canada Voice: +1 (403) 243-2220 Fax: +1 (403) 243-2872 @ + < __/ "Absolutum Obsoletum" - If it works, it's obsolete -------------------------------------------------------------------- ------------------------------ From: Bill Sarkozy Date: Thu, 29 Feb 1996 22:31:30 -0800 Subject: Re: Totally tubular, man At 03:04 PM 2/29/96 -0800, you wrote: > >Where can I find mandrel bent "U" shaped aluminum and steel tubing for >fabricating intake and exhaust plumbing? > > Dan Bocek > dan@xxx.com > > Larson Engineering, Taylor, MI (313) 292-6643, among other places. Also, most header manufacturers supply "assorted bend" kits for headers, although they are all steel and are probably a little heavy for intake plumbing. Good luck...... ------------------------------ From: MTaylorfi@xxx.com Date: Thu, 29 Feb 1996 23:56:42 -0500 Subject: LO VS. HI What is the dynamic difference between low impedence peak-hold injectors and high impedence injectors. Tell me Tell me Tell me. See ya, Mike ------------------------------ From: Andrew Dalgleish Date: Fri, 01 Mar 96 16:49:00 S Subject: RE: Hi-resolution Crank angle sensor On Thursday, 29 February 1996 20:01, owner-diy_efi-outgoing wrote: [snip] > position sensing. For a DIS type system, should be easy to substitute an > optical encoder for the guts of the distributor and get any timing accuracy > you want. [snip] > --------------------------------------------------------------------- > Darrell A. Norquay Internet: dn@xxx.ca > Datalog Technology Inc. Bang: calgary!debug!dlogtech!darrell > Calgary, Alberta, Canada Voice: +1 (403) 243-2220 > Fax: +1 (403) 243-2872 > @ + > < > __/ "Absolutum Obsoletum" - If it works, it's obsolete > -------------------------------------------------------------------- > I tried this about 10 years ago when I did my first 6809-based ignition system on a Nissan A14. The trouble was my system wasn't particularly reliable so I had to carry a normal distributor in the boot and swap them to get home :-) You also have a small amount of mechanical back-lash in the distributor drive. My ideal would be phase from the crank-shaft, and an index pulse from the cam-shaft for TDC. Regards, Andrew Dalgleish Axon Research, Pty Ltd 6 Wallace Ave, Toorak, VIC 3142 AUSTRALIA Tel +61-3-9826-5538 Fax +61-3-9824-0083 ------------------------------ From: Mika.J.Tuominen@xxx.com Date: Fri, 1 Mar 96 09:08:21 +0200 Subject: Re:Ducted Fan Engine >If you reduce compression and fit a spark-ignition-system, you can = >use normal-gas without nitro and therefore won't have any corrosion = >inside the housing. Why not use use straight fuel with no nitro - no corrosion. (and yes, less power 10-15%) >A model-engine normally is very reliable for years (exept = >race-engines which sometimes make more than 32000 RPM!) Due to some experience, I agree... >But I would also prefer electrical motors.. I would say that, those are much easier to start! There is available very powerful electric motors to be used in electric r/c aeroplanes, those might be usable also. I think they = are available about same power levels as glow-plug model engines. Mika =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D Mika J. Tuominen Internet: mitu@xxx.com Nokia Mobile Phones Ltd. Address: P.O.box 86, FIN-24101 Salo, Finland = ------------------------------ End of DIY_EFI Digest V1 #61 **************************** 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".