DIY_EFI Digest Sunday, 6 October 1996 Volume 01 : Number 302 In this issue: RE: drive-by-wire RE: drive-by-wire Re: DIY Traction Control? Re: DIY_EFI Digest V1 #298 re: RE: drive-by-wire See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: Bruno! Date: Sat, 5 Oct 1996 22:23:04 +1000 (EST) Subject: RE: drive-by-wire On Fri, 4 Oct 1996, Daniel Ridge wrote: > However, the thing I really can't stand -- trunks and engine bay latches > that operate only by cable. My Fiat X1/9 is such a car. Is there some > solenoid that I can buy cheaply from a yard that I can install to tug on > the cables for me? Try a central locking solenoid from a car that was equipped with one, or go down to the local car/electronics store, which might have central locking solenoids and stuff which you should be able to buy. While you're at it, the doors could cop a bit of automation as well. Back to diy.... Bruno. (b.marzano@xxx.au) 1977 Celica liftback (engine's knackered) 24" Repco road bike (front fork's rooted) 20" Oxford BMX (daily transport) ------------------------------ From: Daniel Ridge Date: Sat, 5 Oct 1996 09:16:48 -0400 (EDT) Subject: RE: drive-by-wire > > However, the thing I really can't stand -- trunks and engine bay latches > > that operate only by cable. My Fiat X1/9 is such a car. Is there some > > solenoid that I can buy cheaply from a yard that I can install to tug on > > the cables for me? > > Try a central locking solenoid from a car that was equipped with > one, or go down to the local car/electronics store, which might have > central locking solenoids and stuff which you should be able to buy. > While you're at it, the doors could cop a bit of automation as well. The thing is, I'm not trying to add automation gratuitously. The cables are currently pulled on by a pair of levers hidden in the driver's side door jamb. If the levers don't retract the entire way, they get bent and the box they're in gets smashed when the door is closed. It drives me insane. In this case, I feel adding the solenoids would increase robustness. - -Dan PS: we were talking a while ago about non-circular pistons. Wouldn't non-circular piston rings be difficult? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\___/~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Daniel Ridge | USRA CESDIS Research Minion, Beowulf Project | Code 930.5 email: newt@xxx. W274 tel: 301-286-3062 | Goddard Space Flight Center fax: 301-286-1777 | Greenbelt, MD. 20771 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\_|_/~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ http://cesdis.gsfc.nasa.gov/people/newt ------------------------------ From: "Chuck Tomlinson" Date: Sat, 5 Oct 1996 14:16:34 -0400 Subject: Re: DIY Traction Control? > From: MaxBoost@xxx.com > > How about a DIY traction control system? > > Relatively simple comparison of wheel speeds (most cars have abs these days, > so parts are readily avail). Wire into the injector ground circuit back to > the ecm and drop cylinders as needed. Use a pic processor and some drivers > to interupt the ground circuit. > > Also need an on off switch on the dash as well as a pot to adjust the > percentage of slip allowed. (got to have the switch so you can turn it off > and roast the tires :) IMHO, engine-based DIY TCS much more feasible than DIY ABS. My only (theoretical) reservation about dropping cylinders is that it may introduce some crank-killing harmonics. I'd probably want to use a stronger crank than normal, and a viscous torsional damper. A really sweet setup could use a secondary throttle as well. This motor- driven throttle would be normally wide open (spring loaded). I'd probably limit the travel of the sec'y throttle to prevent it from going too close to fully closed. That way you still have a little power if your TCS goes nuts on you when you're pulling out into traffic =8-0 Anyway, I can offer a few simple tips for anyone who wants to try TCS. 1) Use the undriven wheel on each side as the speed reference for the driven wheel on that side. The system will be less likely to trigger in tight turns. 2) Consider retarding the spark (if you can) as a fine-tuning torque control: smoother operation in marginal traction conditions. 3) If you have an electronic auto trans, consider commanding an upshift if TCS is active too long. This is not good for racing, but it's smoother on slippery roads. 4) Consider varying your control gains based on the acceleration of the reference wheels. If TCS triggers and the ref accel is low, then you're on a slippery surface. More conservative speed control may be appropriate on slick roads. 5) Also, if the system triggers and ref accel is negative, you're probably in ABS and your TCS routine should _not_ take action. - -- Chuck Tomlinson ------------------------------ From: Matthew Beaubien Date: Sat, 5 Oct 1996 13:00:45 -0600 (MDT) Subject: Re: DIY_EFI Digest V1 #298 This is all quoted because I have a little to say to each person, so don't flame me ;-). > >>I just got my '70 302 Ford running with the Holley Projection 4DI ECU. This > >>is a batch fire MAP system. The cam is a high lift (.550"), medium duration > >>(224@xxx. The system indicates that at > >>least a -50% correction is required at idle, 700RPM, to get the mixture > >>correct if the stock 302 look up table is used. The injection volume table > >>is based on RPM and MAP signal. If you're using the stock table, the FI will run way too rich. Your vacuum will be less than a stock engine (because of the cam) and the computer sees less vacuum as more load = more fuel. If you lower the fueling requirements in the maps, drivability should improve a whole bunch. One indicator of how close your map is to what the engine needs is the O2 correction. You stated that the O2 correction was -50% at idle. This is telling you that even cutting the fueling requirements it thinks you should have by 50%, it is still running rich. It takes a long time but if you have enough patience, you should be able to make it work ok. > Oh no! Not a Holley! I hope you don't have the 4Di. That system is > terrible. The one with the knobs on it is much better. I recently worked > on a 93 Liconln Town car with a big block 605 in it. Carbs didn't work > too well so they put on the digital Holley system (4Di). Damn thing > would barely run. > Holley just didn't put enough control into the thing (like how much RPM > you can add in hi-cam mode). They try to use a standard O2 sensor for > wide range control. Put a scope on it and it was WAY off. I will > eventually put an EEC on it to get it to run right. Car is real strange. > Canary yellow, BIG wheels/tires and probably 600 HP. When I'm driving it > around people just laugh....until I push the throttle a little bit!!! The fuel map you were using with the 4Di was probably way off. Something must not be right if the carbs didn't work properly (too big, not enough vacuum, etc?). If anything, it probably has too much control making it difficult to tune. I would say the Holley FI with the knobs (Projection) is even worse than carbs. A friend of mine spent _hours_ on a dyno with a Projection on a kids 383 and could not get the thing to run right. The thing would kill holes at the bottom from running too rich and lean them out to near critical temps at the top (or vice-versa). It would bog when it was leaned on no matter what. The "Projection" manifold was one sorry piece wrt distribution. Holley tech guy said it hadn't been dynoed but was "based" on ZZ3 manifold. Holley eneded up buying back the system and giving my friend with the dyno a Holley performance package with heads, cam etc. Another strike against Projection is the fact that Summit stopped selling it because people had too many problems with it (not only tuning but reliability). They ended up bolting on a 750 on a Victor Jr and gained 20+ ft-lbs _everywhere_ compared to the best Projetion runs (even on the Victor Jr.) I don't know how many people have checked out other FI setups but from talking to people "in the know", Accel's DFI seems to be about the best (especially on forced induction engines) for the price. There's also the FI setup that doesn't require a laptop to program. It has a knob where you can adjust the mixutre +/- 50% while driving to get the map to where you want. It's called SDS and there hompage is www.sdsefi.com. I know a few people that have used it with decent success. The wiring harness is a little lame but it works pretty good and is affordable. Matt. mbeaubie@xxx.ca ------------------------------ From: dave.williams@xxx.us (Dave Williams) Date: Sat, 05 Oct 1996 19:20:00 +0000 Subject: re: RE: drive-by-wire - -> but why do European cars have those small pathetic sub-3 liter - -> engines? AFAIK Europe never had V8 engines in 'normal' cars. Only - -> European V8 I know of outsid expensive british sportscars or luxary - -> cars would be the opel diplomat back in the 60s? European countries typically tax automobiles by displacement and number of cylinders. Much over 2.5 to 3.0 liters and your potential market is going to be scared off by what it will cost to get the car registered. The US' various states typically tax by weight instead of displacement. The range is also typically small - the lightest car is $19/yr where I live, $26 for the heaviest, though other states might be as much as ten times more expensive. Italy and Japan are probably the worst for displacement taxes, which is why you see so much work done on high performance sub-1-liter cars for their home markets. It's cheaper and more reliable to do the same thing with displacement, which is what they do for export models. ------------------------------ End of DIY_EFI Digest V1 #302 ***************************** 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".