• From: Van Nuys, CA
  • Registered: 2011-02-11
  • Posts: 3,862

Topic: Engine Computer question

So, if you are running a car from the mid 1980's thru the current day, do you 1) just cross your fingers and trust the factory computer will survive. 2) pull and extra from a junk yard as a spare and hope it's good 3)swap it all out and go to points, condensor, and a 1 barrel Rochester?

No Lemons specific, but is there a junk yard available engine management system that is widely held to be easily adaptable to home built projects?

Woody

Constructor/Owner/Driver - Billy Beer Ford Futura

Parkwod60's Website

  • From: WPB Fl.
  • Registered: 2010-10-27
  • Posts: 1,571

Re: Engine Computer question

The less you change things that already work the more reliable, but this is Lemons, so

"3)swap it all out and go to points, condenser, and a 1 barrel Rochester" is a no brainer

Homestead Chump 5th-Sebring 6th-PBIR Lemons 9th - Charlotte Chump  CrashnBurn 9th
Sebring 6th again -NOLA Chump 1st -PBIR Chump Trans Fail 16th
Daytona 11th - Sebring 6th - Atlanta Motor Speedway 2nd - Road Atlanta Trans Fail 61st-Road Atlanta 5th
Daytona 13th - Charlotte 9th - Sebring 2nd-Charlotte 25th broken brakes - Road Atlanta 14 10th-Daytona 14  58th- Humid TT 19th Judges' Choice!
  • From: Van Nuys, CA
  • Registered: 2011-02-11
  • Posts: 3,862

Re: Engine Computer question

I'm thinking stick with what it cam with, and bring a 1 barrel side draft carb from a motorcycle.  I case of something going bad, I will make an adapter out of duct tape and bring a big box full of jets.

Constructor/Owner/Driver - Billy Beer Ford Futura

Parkwod60's Website

  • JThw8
  • JThw8
  • Administrator
  • Offline
  • From: Mullica Hill, NJ
  • Registered: 2009-06-10
  • Posts: 1,781

Re: Engine Computer question

I gotta be honest, Im an old school carbs and points guy but I have never NEVER had an ECU fail on me.   The Wartburg's ECU was mounted in a rather bad spot where during the 3000 miles or so of BABE it was subjected to....ummmm...copious amounts of moisture....and it still keeps trucking along.   The ECU would be the least of my worries.

http://wartburg.misfittoysracing.com
OTTER: "I think that this situation absolutely requires a really futile and stupid gesture be done on somebody's part."
BLUTO: "We're just the guys to do it."

JThw8's Website

  • From: Baltimore, MD
  • Registered: 2010-05-20
  • Posts: 1,745

Re: Engine Computer question

If you don't weld on the car with the ECU in, and you don't bake it in engine heat, there isn't much you can do to kill it.

As for homebrew engine management, megasquirt. It's not really doable on a lemony budget unless the rest of the car was free, but you can adapt ANYTHING with that system.

Driver, Pit Monkey, Rod Buster and Engine Fire Starter
Team FinalGear
  • From: Choctaw, Oklahoma
  • Registered: 2009-11-12
  • Posts: 2,144

Re: Engine Computer question

Keep the stock setup, but have a carb ready.

I was chatting with a guy at work the other day and he was saying a lot of hot rodders are using a Ford EFI setup on engines (EEC-IV?), but I haven't seen it yet.

  • From: Columbus, OH
  • Registered: 2009-05-26
  • Posts: 2,839

Re: Engine Computer question

JThw8 wrote:

I gotta be honest, Im an old school carbs and points guy but I have never NEVER had an ECU fail on me.

THIS x100.  The ECU is probably the most reliable part of a Lemons car.  Points and carbs go bad way more often.  The only reason people think of computers as being a trouble spot is because of the 'black box' effect where they don't know how or why they fail so when they do it's an indictment of all electronics everywhere in the universe.

If you have a spare computer, you'll be set for the next century of racing.  Unless you do something to kill it.

Quad4 CRX - Wartburg 311 - Civic Wagovan - Parnelli Jones Galaxie - LS400 - Lancia MR2 - Boat - Sentra - 56 Ford Victoria
Known Associate of 3pedal Mafia, Speedycop, and the Russians.  Maybe even NSF.

8 Reply by djcommie (edited by djcommie 2011-02-21 09:46 AM)

  • From: Santa Margarita, CA
  • Registered: 2009-06-03
  • Posts: 177

Re: Engine Computer question

Keep the ECU somewhat cool near a factory location. I have mine mounted on rubber isolators on the floor, where it was behind the dash before.

Black box effect is one of those where people are so stupid its scary. If you can't figure out the basics of the world operates with HowStuffWorks.com holding your hand as you remember grade school math, then you probably can't figure out how to keep from drooling. I don't know if the BS judges would let you on the track whilst drooling.  Is it discrimination? I'm suing.

Team Dai Hard Home Page

1989 Daihatsu Charade

djcommie's Website

  • BoB
  • BoB
  • Lemons Staff Stalker
  • Offline
  • From: Elmhurst, IL
  • Registered: 2009-05-01
  • Posts: 4,206

Re: Engine Computer question

I never thought to much about it.  On my car its actually inside the car by where the glove compartment used to be.  I guess next time I'm in the junkyard I can start looking for a spare, by having a spare with me it will pretty much guarantee that the ecu will never go bad.

Racing 4 Nickels - 1989 Oldsmobile Cutlass Ciera
2011 SHOWROOM-SCHLOCK SHOOTOUT  IOE Winner
2012 The Chubba Cheddar Enduro Class C winner
Facebook Page

BoB's Website

  • jrbe
  • Effluent
  • Offline
  • From: Central CT
  • Registered: 2009-06-23
  • Posts: 921

Re: Engine Computer question

Google search diyefi.  They use gm computers to run all sorts of engines.

-Killer B's (as in rally) '84 4000Q 4.2V8. Audis never win?
  • From: Houston, TX
  • Registered: 2009-10-06
  • Posts: 1,008

Re: Engine Computer question

EyeMWing wrote:

If you don't weld on the car with the ECU in, and you don't bake it in engine heat, there isn't much you can do to kill it.

As for homebrew engine management, megasquirt. It's not really doable on a lemony budget unless the rest of the car was free, but you can adapt ANYTHING with that system.

Not true!  Be very very very careful while installing the kill switch - if you do it wrong (which we've done) it will kill your ECU.  Once you get past that hurdle, then life is pretty much worry free.

Granted, we created ECU destruction before our first race when we were very green, but I'm just sayin' that it can happen.

Regarding your original three option question - go with #1, provided that you test your kill switch well in advance of a race.  If your kill switch doesn't kill your ECU, you're golden.  If your kill switch does kill your ECU, there are work arounds AND you'll have time to find a replacement.

I'm the doctor who is a wife. Which makes the grease hard to explain to my patients... www.tetanusneon.com.

Dr. Wife's Website

  • DaveH
  • DaveH
  • Ripened Lemon
  • Offline
  • From: Delaware
  • Registered: 2009-05-11
  • Posts: 264

Re: Engine Computer question

doctawife wrote:
EyeMWing wrote:

If you don't weld on the car with the ECU in, and you don't bake it in engine heat, there isn't much you can do to kill it.

As for homebrew engine management, megasquirt. It's not really doable on a lemony budget unless the rest of the car was free, but you can adapt ANYTHING with that system.

Not true!  Be very very very careful while installing the kill switch - if you do it wrong (which we've done) it will kill your ECU.  Once you get past that hurdle, then life is pretty much worry free.

Granted, we created ECU destruction before our first race when we were very green, but I'm just sayin' that it can happen.

Regarding your original three option question - go with #1, provided that you test your kill switch well in advance of a race.  If your kill switch doesn't kill your ECU, you're golden.  If your kill switch does kill your ECU, there are work arounds AND you'll have time to find a replacement.

So... for a more technical explanation of "don't f- up your kill switch install":

Don't open-circuit your alternator output when you open the kill switch, especially if the kill switch leaves it connected to the electronics.  The alternator will spike to a buttload of volts and destroy whatever is connected to it.

Here's the skinny:

WRONG (Kills your alternator)
http://farm6.static.flickr.com/5300/5466875142_b4be79abb1_z.jpg

REALLY WRONG (Kills your ECU and pretty much everything else)
http://farm6.static.flickr.com/5015/5466875162_4048851ff5_z.jpg

RIGHT
http://farm6.static.flickr.com/5020/5466875124_8324debc4a_z.jpg

The correct wiring will allow the field from the alternator to discharge into the battery instead of into your ECU.  You need a fusible link near the battery on the alternator line to protect the cabling in case of a short.

Back on the original topic, the ECU is the most reliable thing on your car.  Don't worry about it.

Dave Heinig - Schumacher Taxi Service
coROLLa - 2 time loser, RWB MR2 - 5 time loser
The Craptation - IOE WINNER! Lemons South Spring 2010
Crown Vic - Please God Don't Ever Make Me Go Through That Again

DaveH's Website

  • From: Houston, TX
  • Registered: 2009-10-06
  • Posts: 1,008

Re: Engine Computer question

DaveH wrote:
doctawife wrote:
EyeMWing wrote:

If you don't weld on the car with the ECU in, and you don't bake it in engine heat, there isn't much you can do to kill it.

As for homebrew engine management, megasquirt. It's not really doable on a lemony budget unless the rest of the car was free, but you can adapt ANYTHING with that system.

Not true!  Be very very very careful while installing the kill switch - if you do it wrong (which we've done) it will kill your ECU.  Once you get past that hurdle, then life is pretty much worry free.

Granted, we created ECU destruction before our first race when we were very green, but I'm just sayin' that it can happen.

Regarding your original three option question - go with #1, provided that you test your kill switch well in advance of a race.  If your kill switch doesn't kill your ECU, you're golden.  If your kill switch does kill your ECU, there are work arounds AND you'll have time to find a replacement.

So... for a more technical explanation of "don't f- up your kill switch install":

Don't open-circuit your alternator output when you open the kill switch, especially if the kill switch leaves it connected to the electronics.  The alternator will spike to a buttload of volts and destroy whatever is connected to it.

Here's the skinny:

WRONG (Kills your alternator)
http://farm6.static.flickr.com/5300/546 … abb1_z.jpg

REALLY WRONG (Kills your ECU and pretty much everything else)
http://farm6.static.flickr.com/5015/546 … 1ff5_z.jpg

RIGHT
http://farm6.static.flickr.com/5020/546 … bc4a_z.jpg

The correct wiring will allow the field from the alternator to discharge into the battery instead of into your ECU.  You need a fusible link near the battery on the alternator line to protect the cabling in case of a short.

Back on the original topic, the ECU is the most reliable thing on your car.  Don't worry about it.

And THIS is why we love Dave.

I'm the doctor who is a wife. Which makes the grease hard to explain to my patients... www.tetanusneon.com.

Dr. Wife's Website

  • RobL
  • RobL
  • Lemons Staff Stalker
  • Offline
  • From: Philly area
  • Registered: 2009-04-30
  • Posts: 2,721

Re: Engine Computer question

DaveH wrote:

REALLY WRONG (Kills your ECU and pretty much everything else)
http://farm6.static.flickr.com/5015/546 … 1ff5_z.jpg

FYI, one of the symptoms of this is that your lights/wipers/etc. will stay lit while the engine winds down.

--Rob Leone Schumacher Taxi Service
We won the IOE at Southern Discomfort.
We got screwed at The Real Hoopties of New Jersey  and we took cars down with us.
We got the curse at Capitol Offense but they wouldn't let us destroy the car.

RobL's Website

  • From: San Diego, CA
  • Registered: 2009-04-30
  • Posts: 1,640

Re: Engine Computer question

If you have an E30, bring a spare computer or 3. We've gone through two already.

The Homer: Powerful like a gorilla, yet soft and yielding like a Nerf ball.
  • From: Central CT
  • Registered: 2010-12-29
  • Posts: 393

Re: Engine Computer question

In reality, you're MUCH more likely to have a problem due to a bad sensor, sensor wiring, or ECU output wiring problem than a computer problem.

make sure it's isolated from vibration, either with the stock mount system, or some other vibration-isolating mount.    and don't f up the kill sw wiring just like everybody else mentioned....

of course, if you can get a spare cheap, it's not bad to have on-hand as insurance.

Maximum Effort Motorsports - Mid-engine 1979 Chevette - Class C Winner - GP Du Lac Chargoggagoggmanchauggagoggchaubunagungamaugg
New England Long Winter Build Award - 2015
IOE Winner, Loudon Annoying 2011, Judges Choice - Loudon Annoying 2012
Class C & Least Horrible Yank Tank winner - Boston Tow Party & Overhead Cam Bake 2011
  • From: Rockville, MD
  • Registered: 2010-12-15
  • Posts: 1,155

Re: Engine Computer question

Our car is currently sitting out in the elements, computer bolted to the floor, covered in snow. I bet it'll start up just fine tomorrow.

If you want to be on the safe side, open it up, make a list of all the capacitors, and order a bunch of each. Digikey.com is a good source. Capacitors are usually the ones to go bad in a really old car, so just look for the ones that have a bent-out top, like they're about to explode, and replace those. Make sure you have a nice soldering iron.

Of course, if you fry it due to mis-wiring, you're probably better off just getting another one.

K Car Stalker