Timing advance kits...

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Tue 22 Jul 2003 09:09
Timing advance kits... - Moby
Hi

I have seen loads of these for sale on eBay. What I can gather is that its a resistor that replaces your IAT sensor fooling the ECU that the air coming in is much colder... therefore advancing your timing.

Do these "mods" really provide significant[1] power advantages?
Can you expect any premature engine wear/damage?

They claim no change in your fuel consumption - but I find this hard to believe.

TIA
Moby.

[1]
"significant" is a claimed 5-20bhp
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Tue 22 Jul 2003 11:42
Timing advance kits... - benno10
Moby,
i have just aquired one of these kits for a fiver off of ebay. should fit it later this week and i will post the results here,
Ben
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Sun 27 Jul 2003 22:30
Timing advance kits... - kithmo
Save your money and go to any electronics shop and buy a 4.6K resistor for about 20p. Thats all it is. All you do is pull off the Inlet Air Temperature sensor plug and bridge it with the resistor, leaving the plug disconnected. If you haven't got an IAT sensor then do it with the Coolant Temperature sender plug. The only problem with this modification is that if have a more modern car the ECU learns the new resistance value and compensates for it, returning you back to normal power. Also in my opinion, telling the ECU that cooler air is entering the engine will increase the fuel charge (injector duration) which results in a richer mixture and Catalytic converter damage. I would only try this mod on an older car without a Cat and without the learning function ECU.
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Sun 27 Jul 2003 22:32
Timing advance kits... - DavidHM
Sounds like snake oil to me, but I'm more than willing to be proved wrong.
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Tue 29 Jul 2003 10:09
Timing advance kits... - paultta35
Have a look on the internet (google) under "iat resistor mod". There seems to be some contradiction regarding the size & use of the resistor. The main worry so far I understand is that advancing the timing by replacing the sensor completely by too high a resistance defeats the object of the sensor in the first place & could cause pre-ignition under some circumstances. This all depends on how your ECU uses the info from the sensor - Do all ECU's only take into account the intake temp for timing? I doubt it.

I haven't tried it as yet on my 93 Orion 1.6i but its worth looking into.

Some people use a 3 position switch wired to give:
1)std operation
2)4.6K resistor in series with the sensor - for normal road use i.e. ECU is "fooled" into thinking the temp is 20? degrees cooler
3)100K resistor (& no connection to the sensor at all) - for 1/4 mile burn ONLY i.e. wide open throttle setting

I would definitely look into this, but only afte a bit more background checking.
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