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Add 50 hp and 15mpg with a performance chip?
Topic Started: Dec 29 2009, 05:42 PM (10,169 Views)
Metro Fanatic
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This reminds me of the old "TORNADO" or "VORTEX"....remember those pieces of tin?
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Bad Bent
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Facetious Educated Donkey

Whoa, thinking about it again, the Geo is rated at 55 HP and this "chip" will add 50 HP!
Double the HP would be like stuffing twice the gas and air into the cylinders.
Better use 115 octane airplane fuel. :'(

I looked at the eBay sellers "other items" and there are 3,734 items for sale. Every single one is the same 50 HP increase, same price (highest/lowest), just a different name.
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Woodie
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Bad Bent
Dec 30 2009, 12:18 AM
Every single one is the same 50 HP increase, same price (highest/lowest), just a different name.
And every single one of them is a 2 cent resistor that you wire into either the IAT or CTS sensor to fool your computer into giving the engine the wrong fuel mixture. You can fool it rich for more power (pollutes, wastes gas, destroys catalytic converter) or fool it lean to get more mileage (less power, poor starting, knocking, more likelihood of burned valves due to skyrocketing temperatures).

You might even get satisfactory results from one, but when your engine dies six months later, will you remember that you "F"ed with it and lied to your computer, or just pass it off as a crappy engine?
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mwebb
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FOG

for the record
it is not possible to change the mixture from 14.7 to 1
Lambda of 1

as long as MR 02 sensor is cycling , the system is at Lambda of 1 or stoich
Mr 02 sensor can not see anything but stoich or 14.7 to 1 or Lambda of 1

if Mr 02 sensor sees lean condition , voltage will be low
and
if Mr 02 sensor sees rich condition , voltage will be high
either way either condition , will set a DTC for system lean or system rich .

..............................................
so do not frak around and start creating voltage drops in sensor signal connections
you are not able to drive system lean or rich
without coding the system and forcing it to go to open loop -
which is UNdesirable .

but
changing the values mentioned can change the ignition timing Map ...
i would guess , not for the better .
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Dallas


mwebb
Dec 30 2009, 03:39 PM
for the record
it is not possible to change the mixture from 14.7 to 1
Lambda of 1

as long as MR 02 sensor is cycling , the system is at Lambda of 1 or stoich
Mr 02 sensor can not see anything but stoich or 14.7 to 1 or Lambda of 1

if Mr 02 sensor sees lean condition , voltage will be low
and
if Mr 02 sensor sees rich condition , voltage will be high
either way either condition , will set a DTC for system lean or system rich .

..............................................
so do not frak around and start creating voltage drops in sensor signal connections
you are not able to drive system lean or rich
without coding the system and forcing it to go to open loop -
which is UNdesirable .

but
changing the values mentioned can change the ignition timing Map ...
i would guess , not for the better .
under certain circumstances (probably not researched by the people selling these) there is a voltage cutoff for closed loop and open loop (for those who dont know, in closed loop the ecu uses o2 feedback to remain bouncing between lean and rich... called stoich, in open loop it is all pre-calculated pulsewidths from the injector to run richer when colder) at what point the ecu switches it I dont know. on my megasquirt one, I had it set for 60C, it will ignore o2 readings and keep afr around 13.2 until the motor is "warmed up"


but dont ever buy one of these "chips". I just quoted you mwebb, I wasnt correcting anything you said or anything, just adding to what you said :)
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mwebb
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FOG

...."under certain circumstances (probably not researched by the people selling these) there is a voltage cutoff for closed loop and open loop (for those who dont know, in closed loop the ecu uses o2 feedback to remain bouncing between lean and rich... called stoich, in open loop it is all pre-calculated pulse widths from the injector to run richer when colder) at what point the ecu switches it I don't know. on my megasquirt one, I had it set for 60C,

it will ignore o2 readings and keep afr around 13.2

until the motor is "warmed up""....


cool
and without feedback from an AFR sensor or a 02 sensor , just how exactly would MR ECM Megasquirt Know this ?
answer ;

it CAN NOT KNOW

it can only guess

Posted Image
Edited by mwebb, Dec 30 2009, 10:51 PM.
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starscream5000
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Got 70 MPG?

What would be nice for those of us that don't care about the car warming up a little faster or letting it warm up in the morning is a way to make the car stay in closed loop mode right at initial startup... Or is there a way to do this already?
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mwebb
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FOG

starscream5000
Dec 30 2009, 10:47 PM
What would be nice for those of us that don't care about the car warming up a little faster or letting it warm up in the morning is a way to make the car stay in closed loop mode right at initial startup... Or is there a way to do this already?
yes there is
as soon as the 02 sensor starts reporting MR ECM will will listen to it and start adjusting fuel trim based on 02 sensor input
the system will be in closed loop

to the limit of the authority of 02 sensor at the time , MR ECM will not ignore all the other inputs

MR 02 sensor does not start reporting until it is hot enough ......
which is why they started putting heaters in 02 sensors AND
why they have secondary air injection .

so if your car does not have a 4 wire 02 sensor
you can add that to your system , to speed up the time it takes to get into closed loop
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starscream5000
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Got 70 MPG?

mwebb
Dec 30 2009, 10:56 PM
MR 02 sensor does not start reporting until it is hot enough ......
which is why they started putting heaters in 02 sensors AND
why they have secondary air injection .

so if your car does not have a 4 wire 02 sensor
you can add that to your system , to speed up the time it takes to get into closed loop
So how would go about wiring in a 4 wire o2 sensor into a system designed for a 2 wire o2 sensor?
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mwebb
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FOG

starscream5000
Dec 30 2009, 11:03 PM
mwebb
Dec 30 2009, 10:56 PM
MR 02 sensor does not start reporting until it is hot enough ......
which is why they started putting heaters in 02 sensors AND
why they have secondary air injection .

so if your car does not have a 4 wire 02 sensor
you can add that to your system , to speed up the time it takes to get into closed loop
So how would go about wiring in a 4 wire o2 sensor into a system designed for a 2 wire o2 sensor?

black = signal wire
gray = sensor ground

white = heater
white = heater

it does not matter which white wire connects to negative or positive but one must connect to each
use the fuel pump relay for positive
ground is ground for negative

in mine MR ECM has control of the ground side of both 02 sensors , i have not monitored the front 02 sensor heater to see if MR ECM ever switches it off .
the rear heater is switched on at 50mph and while i was monitoring it , never switched off

use an oem 02 sensor for a 1996 geo metro NOT an aftermarket POS
i could take a digital photo of the connections
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Dallas


mwebb
Dec 30 2009, 10:46 PM
...."under certain circumstances (probably not researched by the people selling these) there is a voltage cutoff for closed loop and open loop (for those who dont know, in closed loop the ecu uses o2 feedback to remain bouncing between lean and rich... called stoich, in open loop it is all pre-calculated pulse widths from the injector to run richer when colder) at what point the ecu switches it I don't know. on my megasquirt one, I had it set for 60C,

it will ignore o2 readings and keep afr around 13.2

until the motor is "warmed up""....


cool
and without feedback from an AFR sensor or a 02 sensor , just how exactly would MR ECM Megasquirt Know this ?
answer ;

it CAN NOT KNOW

it can only guess

Posted Image
I meant the ecu will ignore o2 readings (wideband lc1) up until a certain point, where it disables open loop and then reads o2 and corrects
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Coche Blanco
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Troll Certified

I want everyone to read the FIRST reply to this thread. I loled that this got to two pages.
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starscream5000
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Got 70 MPG?

mwebb
Dec 30 2009, 11:13 PM

black = signal wire
gray = sensor ground

white = heater
white = heater

it does not matter which white wire connects to negative or positive but one must connect to each
use the fuel pump relay for positive
ground is ground for negative

in mine MR ECM has control of the ground side of both 02 sensors , i have not monitored the front 02 sensor heater to see if MR ECM ever switches it off .
the rear heater is switched on at 50mph and while i was monitoring it , never switched off

use an oem 02 sensor for a 1996 geo metro NOT an aftermarket POS
i could take a digital photo of the connections
If it wouldn't be too much trouble...
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Murf 59
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I like the dead horse. Whip it again
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