DIY_EFI Digest Saturday, 7 November 1998 Volume 03 : Number 526 In this issue: Re: MAF Re: FreeDIACOM ? (long) Re: AFR Re: GM Engine Sizes (was Chevy engines) Re: Motronic Re: Motronic Re: HEI Coil Wires Re: No sumcheck code in a '95 MEMCAL Questions about Big Block Chevy Tall Deck Engines Re: Questions about Big Block Chevy Tall Deck Engines Re: GM Engine Sizes (was Chevy engines) Excellant site on oxygen sensors Re: MAF Re: multiple ECU/EFI q? Re: PIC Questions Re: Questions about Big Block Chevy Tall Deck Engines BOUNCE diy_efi: Admin request (fwd) See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: bearbvd@xxx.net (Greg Hermann) Date: Fri, 6 Nov 1998 12:46:48 -0700 Subject: Re: MAF >> >also you are relating the VE to the size of the injectors >> >this really has nothing to do with it >> >just supplies a number that is the max VE that the FI could support >> >with these injectors >> >increasing size 17% or fuel pressure 35% would allow the same injector to >> >support 100% VE at your indicated 5300 RPM >> >> All I was doing was calculating the VE for the particular operating >> conditions which were stated---170 gr./sec. @xxx.8 liter 4 >> stroke engine , as an example of how to do the calculation. >> >> Of COURSE maximum injector duty cycle % will occur at maximum VE (which > I stand corrected here--(Zapped PROM early in AM). Longest injector PULSE WIDTH (time open) is what occurs at maximum VE point, maximum injector DUTY CYCLE % (Pulse width/time between pulses) is what occurs at MAX air flow. Awake now--- :-) Regards, Greg ------------------------------ From: xxalexx@xxx.com Date: Fri, 6 Nov 1998 02:49:50 +0000 Subject: Re: FreeDIACOM ? (long) What year is your car? I looked at some 97 Dodge Van data with a snapoff at inverted 8192 baud, last year. Since car was OBD-2, I was expecting a J1850 protocol and J1979 or J2190 code. Instead i got the dump you stated. req. send $14 $14 id id data id's would increase randomly up to $5B then id $12 would req 11 bytes car would respond with 22 bytes then id's would recycle again from $02 200-300us req. send delays which faster than SAE. I think i also picked up a strange init. seq. I got interested in this when SAE published the first HS-3000 book in 95. Presently working on various scams, hopefully as a proffesion due to credit cards and no job. alex ------------------------------ From: "Walter Sherwin" Date: Fri, 6 Nov 1998 17:10:05 -0800 Subject: Re: AFR Usually the factory O2 sensor is good enough as a naturally aspirated tuning aid, in combination with other computer data and performance testing. Wide band O2 sensors are a must if you are artificially aspirated. Good wide band O2 sensors are a nice tool in any situation, if you have the bucks. I like the Bosch LA1, LA2, LA3 or the Engine Control & Monitoring (ECM) Lambda Pro. Now convincing your wife that she really wants one of these for X-Mas is your next challenge............. - -----Original Message----- From: Geoff & Sue Richards To: Diy_Efi Date: Friday, November 06, 1998 6:00 AM Subject: AFR >is AFR tester necessary for modifications or scan tools good enuf >just wonderin >Thanks >Geoff > ------------------------------ From: bearbvd@xxx.net (Greg Hermann) Date: Fri, 6 Nov 1998 16:18:59 -0700 Subject: Re: GM Engine Sizes (was Chevy engines) >Curtis writes................... > >> The 350 you have is a pontiac 350 (assuming it wasn't swapped >>out). Its actual displacement was 354. They called it the 350 because >>chevy had such good luck with their 350. > > >All this talk about GM engines leads me to postulate a theory about GM >engine size and ask if anyone really knows... > >In the fifties and prior each division had its own frame and suspension, own >transmission (although some shared Hydra-matic) and own engines. In 65 the >Turbo Hydramatic came out and over several years became the GM-wide >transmission. > >My theory is that GM was planning from the early sixties to simplify their >engine families. >That would explain why in 1967 all the divisions standardized on 350 and 400 >cu in instead of what they had prior. Chevy went from 327 to 350. Stroke on >the 350 is 3.48 inches. Always prior the stroke had been a fractional number >(3 inches or 3 and one quarter). Rodders had been making 352 cu in small >blocks for a number of years ( 4 inch bore and 3 1/2 stroke) so you'd have >expected Chevy to go for a 352. I figure it had to be corporate policy >telling the divisions to all come up with 350 so that in subsequent years >one of the 350 blocks could become the GM standard. That is what they >eventually did, sort of. > >Interesting part to me is how Chevy did and did not play along with this. >They did the 350, but kept the 396 unchanged instead of making it a 400. >Few years later they increased it to 402 and badged it a 400. I have a 72 >pickup with a 402 that says 400 on the fender. In the manual the various >engines are listed. The 307 is a 307, the 350 is a 350, the 454 is a 454, >but the 402 is a 400. Also note that then all the other divisions went from >427 or 428 to 455, Chevy instead went to 454. > >Sounds like politics within GM to me. Or am I reading too much into it? I >presume Chevy kept the 396 because they had vehicles (SS396) based on that >number. That doesn't explain the 454 vs 455 though. > >Comments? > >Gwyn Reedy >Brandon, FL Part of it was a corporate edict to the effect that no cubes over 400 would be allowed in an intermediate size (B-body) vehicle. Another edict was no more than 4 carb holes on such vehicles. I think 350 may have been another size edict, for another vehicle class. On the really big cube motors, there were no edicts as to cubes vs. body type, so they varied. 427's, of course were all due to the early '60's NASCAR 7 liter max. rule. Do not remember whether NHRA did a 7 liter max for a while too, or not. I think that 428 was a common GM size due to an edict about making sure that the big motors did not go racing. All due to political concern over hipo stuff. Later, concern over anti-trust action, far more than economics (gummint make 'em split off Chevy??), led to cross division parts use and assembly division separate from the car divisions. GMC trucks used to use Poncho V-8's in late '50's, too. GMC also had an inline 6 that not a lot of folks remember, a fuzz over 300 CID, which was a serious torque monster, and extremely durable. Did very well in C-gas and D-dragster type NHRA stuff. Not a lot of people realize that the (later) GMC 307 CID V-6 truck motor was a sawed off 409. Or that they built a 351 CID V-6 and (a times 2) 702 CID V-12 (both truck motors). O, P & Cad used the old 4 speed hydramatic from its inception in the late '40's till the end. Buick used the two speed Dyna-Flow/Powerglide with a 5 element converter from late forties till whenever. EXCEPT the Hydramatic div. plant burned to the ground, I think in late '54, so you can find some thing like Power Glide '55 Ponchos that were built factory stock on an emergency basis. I have even seen early '50's Cads with a power steering pump which said "Vickers" right on the pump. TH 400 came out in '63 or so ???? (Believe Caddy was last to change over from a four speed, this may be when they did it.) Chevy used the Power glide till later ('65??) when the TH350 came out. (They finally figured out how to build a three speed cheap and junky enough to suit Chevy!! :-) Aren't dictators funny critters???! Regards, Greg ------------------------------ From: "John Thacker" Date: Fri, 6 Nov 1998 23:23:47 -0000 Subject: Re: Motronic Retrying hoping for a reply - -----Original Message----- From: John Thacker To: diy_efi@xxx.edu> Date: 05 November 1998 21:19 Subject: Motronic >Hello.. > >how can I get a o/p from the diagnostics socket on a motronic system?I've >tried pressing the gas method. any idea how and what format it will take >secondly >Any ideas of how can I interface my Motronic with a PC (IBM >compatible) ? > ------------------------------ From: xxalexx@xxx.com Date: Fri, 6 Nov 1998 06:02:44 +0000 Subject: Re: Motronic > > > >how can I get a o/p from the diagnostics socket on a motronic system?I've > >tried pressing the gas method. any idea how and what format it will take > >secondly > >Any ideas of how can I interface my Motronic with a PC (IBM > >compatible) ? > > It could use the ISO-9141 or 9141-2 protocol, I have a rs232 adapter for this, but have not tried it out on a non OBD-2 protocol there was some info. on changing keywords and baud in archives from landshark who was working on motronic. The best method to do this is if you know a dealer and then record the scan session with a protocol analyzer. alex ------------------------------ From: The Thibodeaus Date: Fri, 06 Nov 1998 19:10:28 -0500 Subject: Re: HEI Coil Wires I spoke with Crane Electronics tonight, the answer I got was that the plugs on the end of the wires are slightly different. The coils (red & white wires, red & yellow wires) are the same. Bob T At 12:29 PM 11/6/98 EST, you wrote: >In a message dated 98-11-06 11:33:16 EST, you write: > ><< s far as I know, the 2 coils are different. I think the reason is the > control module in the bottom of the distributor. One coil is for the older > module w/only 4 wires on it, the other for the newer, 6 wire module. Maybe > one might draw too much current on the primary side and toast the module? > >> > the coil draw no current. it produces a sine wave. >if I find > ------------------------------ From: Scot Sealander Date: Fri, 06 Nov 1998 20:57:20 -0800 Subject: Re: No sumcheck code in a '95 MEMCAL Ludis Langens wrote: > Has anyone else found a MEMCAL like this? No checksum? Yes, the 3800 code. It has the routine, it is just never called. Scot Sealander Sealand@xxx.com ------------------------------ From: "Gwyn Reedy" Date: Fri, 6 Nov 1998 22:26:44 -0500 Subject: Questions about Big Block Chevy Tall Deck Engines Don't know just where to go for help with this kind of information. Any answers or leads gratefully appreciated. 1. What was the bore and stroke of the 366 engine? 2. What is the purpose of the tall deck engines used in trucks? Bore and stroke are the same as passenger engines (standard deck height)so is it for better water circulation? 3. Apparently they have the same bore and stroke as standard deck height engines, so can standard cranks and rods be used? Are the heads the same? 4. Known differences: pushrods are longer, intake manifolds and water pumps are different to allow for better cooling. Hope there is some engine historian out there who can help me out on this. I'm trying to put together a 1970 C-50 truck with a 427 engine. The block and crank may be bad on this one (I haven't taken it apart yet) but I know where to get several 366 engines. Want to figure out if I can put a longer stroke crank in a 366 (and what displacement will it give) or if I can slip a 454 block under the 427 truck heads and manifold. ------------------------------ From: ECMnut@xxx.com Date: Fri, 6 Nov 1998 23:54:29 EST Subject: Re: Questions about Big Block Chevy Tall Deck Engines I'll try & find it in print for you, but my "8 track" era brain recalls the 366, 396, 402and 427 truck and car haveing the same crankshaft demensions, while all the high decks had forged ones. High deck engines had longer connecting rods to compensate for the one inch higher deck, and reduce piston skirt side loads.. 4 bolt mains, thicker decks and cyl walls. The 366 heads were terrible from a flow standpoint. HTH BTW, 8-tracks rule! > Hope there is some engine historian out there who can help me out > on this. I'm trying to put together a 1970 C-50 truck with a 427 > engine. The block and crank may be bad on this one (I haven't > taken it apart yet) but I know where to get several 366 engines. > Want to figure out if I can put a longer stroke crank in a 366 > (and what displacement will it give) or if I can slip a 454 block > under the 427 truck heads and manifold. > ------------------------------ From: Tom Sharpe Date: Fri, 06 Nov 1998 22:58:38 -0600 Subject: Re: GM Engine Sizes (was Chevy engines) Gwyn Reedy wrote: > All this talk about GM engines leads me to postulate a theory about GM > engine size and ask if anyone really knows... > > Comments? > > Gwyn Reedy > Brandon, FL 421,425, 426, 427, 428 engines from Ford, GM and Chrysler were all <= 7 Liters, the FIA limit, same as the 5 liter (302) limit. The 428 Ford is actually at 426, but that name was already taken. The marketing name often did not match the actual displacement, ie 396 and 402s called 396 and 400. PS there's a 454 in every garbage truck in the country! Regards Tom ------------------------------ From: ARoss10661@xxx.com Date: Sat, 7 Nov 1998 00:05:49 EST Subject: Excellant site on oxygen sensors There is alot to be said for having eclectic interests. I was searching a PIC project page and found an excellant site with MUCH O2 sensor info. The URL is: http://www.bobblick.com/bob/auto/o2sensor.html Hope u find it useful Al ------------------------------ From: Tom Sharpe Date: Fri, 06 Nov 1998 23:14:17 -0600 Subject: Re: MAF Greg Hermann wrote: > >> > >> Sorry--spaced out showing the VE calc--so here it is: > >> > >> (7) 3.8 liters x 61 cubic inches/liter = 232 cubic inches > >> > >> (8) 232 cubic inches/revolution / 2 revolutions/cycle x 5300 > >> revolutions/minute = 614800 cubic inches/minute. > >> > >> (9) 614800 cubic inches/minute / 1728 cubic inches/cubic foot = 356 cubic > >> feet/minute (theoretical swept intake volume) > >> > >> (10) 299.6 cfm/356 cfm = 84.2% VE (actual intake air volume/theoretical > >> swept intake volume) ((3)/(9)) > > > >except max VE occurs at ( or very near) max torque > >not at the max flow rate of the injectors if porperly sized > >real VE for this setup would be in the 95-100% range if the torque peak is in > >the 3500 range > > > >also you are relating the VE to the size of the injectors > >this really has nothing to do with it > >just supplies a number that is the max VE that the FI could support > >with these injectors > >increasing size 17% or fuel pressure 35% would allow the same injector to > >support 100% VE at your indicated 5300 RPM > > > >Clive > > All I was doing was calculating the VE for the particular operating > conditions which were stated---170 gr./sec. @xxx.8 liter 4 > stroke engine , as an example of how to do the calculation. > > Of COURSE maximum injector duty cycle % will occur at maximum VE (which > occurs at maximum bmep, and at a lower engine speed, one which is fairly > near the brake torque peak, if we are going to be truly rigorous about our > semantics.) But the same calculation would apply had the data at that > engine speed been given. Anyone who wanted to develop a VE vs. Rpm curve > could do so by data logging the output from the MAF vs. RPM. Pretty simple > thing to plug into a spread sheet from there. Could tell a person a whole > lot about cam profiles---- > > And YES, peak bmep DOES happen at a DIFFERENT engine speed from brake > torque peak, because friction losses vary with engine speed also! > > Regards, Greg Found a bugggg....... At Maximum VE, Pulse width is at maximum, but, injector duty cycle % continues to rise with RPM as long as VE drops less than RPM increases. Max duty cycle will occur at or after max HP. ( amount of fuel used per time ). Regards Tom ------------------------------ From: Tom Sharpe Date: Fri, 06 Nov 1998 23:27:19 -0600 Subject: Re: multiple ECU/EFI q? Clive Apps Techno-Logicals 416 510 0020 wrote: > I have a 16 valve 4 cyl DOHC with 8 ex and 8 intake ports > I want to set this up with a split personality Last month's hot rod had aftermarket 4 valve heads for the SBC that were street oriented. They created an engine with tremendous torque and HP in the street RPM range and above, with a mild cam and "normal" ports/exhaust, etc. The heads seemed to be worth 150 + HP and FT/LBS. Two valve race engines were able to make more power at higher RPM, as the max flow of the 4 valve heads was about the same, but there was no comparison at all at 4000 RPM. I suggest that you forget the split personality and go for the smooth torque Northstar approach, I love my Aurora. If you're really a glutton for punishment, get the computer, etc from a ZR1 Corvette....... regards Tom ------------------------------ From: Tom Sharpe Date: Fri, 06 Nov 1998 23:51:52 -0600 Subject: Re: PIC Questions Bruce Bowling wrote: > > LCD Display (probabally 4 bit interface) > > RS232 Interface > > 16 Outputs (via 2 74HC595's) > > 8 Inputs (via 74HC165) > > Input for a rotary encoder (2 inputs) > > 2K of Data Storage User Programmable > > (Maybe 93C86 or 24C16 Serial EEPROM) > > > > > Try the PIC16C74A, it has 4K ROM (OTP), 192 bytes RAM, 33 I/O channels > (each w/ 25 ma source/sink), 2 input capture, USART/IIC/SPI, and > is 20 MHz. > > - Bruce PIC Group, I was looking thru the Tech America sale flyer and I saw a cheap device, probably a PIC, that would turn a PC into a 'scope, sampling (at 71hz ?) and playing back thru the parallel port. How about someone building one so that we can sample the O2 sensor and MAP from a running efi system. I think it would be teriffic for the 332 project (or has someone already done that?). I would like to see the trace of the O2 sensor to determine if you can see each exhaust pulse, and if so, what pieces (formula?) to monitor to determine AFR. The same for the MAP sensor... can you see the valves open and close??? Some have to restrict the map sensor line to get the engine to run correctly..... especially with a radical camshaft.. What reading do we use for the EFI???? Regards Tom PS If anyone has any real data, please send it to me.. ------------------------------ From: Tom Sharpe Date: Sat, 07 Nov 1998 00:03:20 -0600 Subject: Re: Questions about Big Block Chevy Tall Deck Engines Gwyn Reedy wrote: > > > Don't know just where to go for help with this kind of > information. Any answers or leads gratefully appreciated. > > 1. What was the bore and stroke of the 366 engine? > The 366/427 tall block had really tall 4 ring pistons. Rods\ crank and heads were the same. There are spacers available to allow regular intakes on tall blocks. The 366 is a small bore, check thickness for overbore. most early 402s can go to 4.250 (427) (+.125) 396 would be +.154, 366 would be +.315..... .160 a side. Most tall block builders use longer rods for better angles/power. 366T = 3.935" x 3.76" 396 = 4.096" x 3.76" 402 = 4.125" x 3.76" 427 = 4.250" x 3.76" 427T = 4.250" x 3.76" 454 = 4.250" x 4.00" 502 = 4.466" x 4.00" T = Tall Deck ALL production big blocks used a 6.135" rod. regards Tom ------------------------------ From: Orin Eman Date: Fri, 6 Nov 1998 22:55:55 -0800 (PST) Subject: BOUNCE diy_efi: Admin request (fwd) > Date: Fri, 06 Nov 1998 12:58:15 -0600 > From: Joe Boucher > Subject: Re: Chevy engines > To: "diy_efi@xxx.edu> > Reply-to: BoucherJC@xxx.com > Message-id: <364346C6.69C456B1@xxx.com> > Organization: Lockheed Martin > MIME-version: 1.0 > X-Mailer: Mozilla 4.04 [en] (Win95; U) > Content-type: text/plain; charset=us-ascii > Content-transfer-encoding: 7bit > You need to join the f-body (GM designation for Camaro/Firebird) list. > Send an email to: list.manager@xxx. > In the message field type: subscribe f-body-classic. > Joe Boucher > '70 RS/SS Camaro '81 TBI Suburban ------------------------------ End of DIY_EFI Digest V3 #526 ***************************** To subscribe to DIY_EFI-Digest, send the command: subscribe diy_efi-digest in the body of a message to "Majordomo@xxx. 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