Tuning GM/factory EFI....

mrvette

Phantom of the Opera
Joined
Mar 24, 2008
Messages
15,207
Location
NE Florida
From other threads some may know I have a older/antiquated speed density EFI on my 355 roller engine, it uses the late 80's tech #1227730 GM computer, call the engine a basic TPI because that's what the electronics is...stock as a stove, except the CalPak/chip in there, that was burnt some years ago....I have a heated plain jane O2 sensor in the collector, just ONE of them....

so the gear to burn chips is still high, plus I tried ditching this system years ago, and it was a NO GO, the programming and 9 pin D connector into any laptop I could find, shot me down BIG TYME....

what is out there NOW, from GM/junkyards that can run this engine, maybe learn a new program so I don't have to mess with it so much, and maybe still run with the HEI??

or have all the designs just left this in the dust and fuggetaboutit.....:hissyfit:

I gotta keep this cheep, spending thousands is totally out, spending a couple hundred is maybe do-able.....

:nuts::gurney:
 
Gene,

Check out the Megasquirt. You're an old ET. You can build it yourself. Here's the link: http://www.megasquirt.info/

Here's another source that might be useful: http://www.diyefi.org/

DC

That is exactly where I went 4? years ago, and it drove me krazy....

too much with the programming, too much with computer interface, and NO ability to send programs over the net for any smart help, and NO one local...

so I went back to this stock POS....which I fairly sure could be updated pretty good for fuel economy and power....

:nuts:
 
Gene,

Check out the Megasquirt. You're an old ET. You can build it yourself. Here's the link: http://www.megasquirt.info/

Here's another source that might be useful: http://www.diyefi.org/

DC

That is exactly where I went 4? years ago, and it drove me krazy....

too much with the programming, too much with computer interface, and NO ability to send programs over the net for any smart help, and NO one local...

so I went back to this stock POS....which I fairly sure could be updated pretty good for fuel economy and power....

:nuts:

I don't recall what the problem is that is driving you towards another ECM. I'm assuming your setup still operates in closed loop mode, so the fueling ought to be pretty close. And, I assume you're running a reasonably calibrated spark curve. What am I missing?
 
Gene,

Check out the Megasquirt. You're an old ET. You can build it yourself. Here's the link: http://www.megasquirt.info/

Here's another source that might be useful: http://www.diyefi.org/

DC

That is exactly where I went 4? years ago, and it drove me krazy....

too much with the programming, too much with computer interface, and NO ability to send programs over the net for any smart help, and NO one local...

so I went back to this stock POS....which I fairly sure could be updated pretty good for fuel economy and power....

:nuts:

I don't recall what the problem is that is driving you towards another ECM. I'm assuming your setup still operates in closed loop mode, so the fueling ought to be pretty close. And, I assume you're running a reasonably calibrated spark curve. What am I missing?

Well, I hear all these great things that the later engines can do, and with more modern computers they getting 30 mpg outta these newer cars somehow, maybe skip firing on the injectors? easy to do with sequential, not so much with batch fire....I take a bit of license, the system works as well as it ever did, just that I wonder about updating to something newer....been 25 years since that was on the drawing boards, afterall.....I really don't think there is much on the table on the ignition end of things, I sorta feel a well timed spark does it, and after that, it's case closed....:lol:

so that leaves the fuel handling, and obviously the induction, and since I"m dumping the hotrod cam in favor of a stock L98, there is yet another chip burn and so on....it goes forever....gas going to 5 bux/gallon, the only solution is to get more MPG....that and I have some minor issues I maybe as well take it all down and do it all at once,......

like the water temp sensor, belongs in the cyl head, not the remote stat housing....there is a 10-15f difference between the head temps and what the computer sees there....right up front in the airstream...that and the timing chain is tired, 100k miles and near 14 years....

the episodes of bad fuel seem to have settled down for the last couple years....much more picky where I buy gas.....I still think lots of that rough running is ethanol related, because some daze it's smooth as silk and others it's rough....so go figger, been all over the wiring several times in 5 years fighting this idle problem....

:cool:
 
. . . the episodes of bad fuel seem to have settled down for the last couple years....much more picky where I buy gas.....I still think lots of that rough running is ethanol related, because some daze it's smooth as silk and others it's rough....so go figger, . . .

Gene,

I think you are exactly right that your fuel problems were (and are) ethanol related. There is a great article in the February 2011 issue of Popular Mechanics magazine regarding problems with ethanol in fuel. Here's a link to the online version: http://www.popularmechanics.com/car...uels/e15-gasoline-damage-engine?click=main_sr

Note there are 2 pages to read online.

I also recently read where it takes more energy to produce ethanol than you get from it as a vehicle fuel. That, the article above, and given the problems the Mississippi delta is having with fertilizer runoff from corn farming, puts me in favor of eliminating ethanol in gasoline. Looks like your "green weenies" were duped by the corn industry.
 
. . . the episodes of bad fuel seem to have settled down for the last couple years....much more picky where I buy gas.....I still think lots of that rough running is ethanol related, because some daze it's smooth as silk and others it's rough....so go figger, . . .

Gene,

I think you are exactly right that your fuel problems were (and are) ethanol related. There is a great article in the February 2011 issue of Popular Mechanics magazine regarding problems with ethanol in fuel. Here's a link to the online version: http://www.popularmechanics.com/car...uels/e15-gasoline-damage-engine?click=main_sr

Note there are 2 pages to read online.

I also recently read where it takes more energy to produce ethanol than you get from it as a vehicle fuel. That, the article above, and given the problems the Mississippi delta is having with fertilizer runoff from corn farming, puts me in favor of eliminating ethanol in gasoline. Looks like your "green weenies" were duped by the corn industry.

Green weenies are inherently insipid....nothing to be said, other than that.....

:bonkers::flash:
 
I read the same thing. Someone got duped, I still don't understand why we have not looked more into diesel fuels. VW has a jetta that gets like 50 something miles to the gallon and the fuel is the less complicated to produce then the 100+ blend of different gas they have. I have a truck that is somewhere like 7500lbs, it can pull just about anything you hook to it and it gets between 20-24 mpg depending on how you drive it.
The hybrid cars do more damage to the enviroment when you look at them from cradle to grave vs a normal car, so I don't get it. It a conspiracy I tell you. I bet some of our leaders in govt own lots of stock in farms that produce corn and companies that produce batteries.:suspicious:
 
Not only that, but now the large amount of feed grains being used for ethanol are driving food costs up by making less available for human consumption.
 
Not only that, but now the large amount of feed grains being used for ethanol are driving food costs up by making less available for human consumption.

What's going to be the problem when they start making ethanol from switchgrass or algae? That PM article was written by a dumb ass. Ethanol has been around for 30 years. Floridians seem to think its a new thing. The rest of the country has been running it all along and nobody's head has exploded.

Gene has a short in his cross wired crossfire and blames it on the greenie wienies.:nuts: He's been having problems with that junkyard special fuel injection since i've known him.
 
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