Intake resister mod?

[VT GEN3]

Hi all,

I have a VT2 SS 6spd. I have the usual bag of tricks, edit, extractors/exhaust, OTRCAI, 3.9diff gears, ported throttle body. 234rwkw

Someone told me about an el-cheapo mod for modifying intake temp sensor by adding a resister to trick the computer to throw in a little more fuel/timing etc. Apparently its like $10 worth of stuff.

Does this mod work, will it cause harm? Does anyone know how to do it. Im not really technically minded, so could someone explain how to do it and what parts I need.

Your help much appreciated..

[Beej]

A complete waste of time - especially if you have had a proper custom tune done already. All this mod would do add the risk of blowing up your engine.

One the whole points of a proper tune is to set your engine up to it will produce the maximum hp/torque at all times under all conditions - consistently. Don't muck with it now it is set up right!

Cheers,

Beej

[VT GEN3]

Ok, (im slapping my hands) leave it alone!!!


what about on a stock car? like for an example a VS commodore 3.8litre?

would it risk blowing up the motor here as well?

[Shmacky]

adding a resister to trick the computer to throw in a little more fuel/timing etc.

I think any form of 'tricking' the computer to think it's doing something when it's not is going to be bad. Maybe not in the short term, but eventually.

Why not trick the computer to think its doing 2000rpm when the needle's at 6500rpm - that way you can rev all the way to a theoretical 10500rpm and get more power? I'll let you test that one for me

Getting back on track, any gain if slightly is hugely outweighed by the risk of destroying the engine.

Shmacky.

[gofaster]

Ok... explain how this resistor could blow up your engine? lol.


The basic theory around this resistor mod is that it tricks your computer to think that the air sucking in is always cold. Hence it will inject more fuel. If anything it will make your car run a bit rich.....which isnt ideal but it won't BLOW your engine up. Long term 200,000kms later who knows?

As with all "cheap" mods everybody is sceptical. I haven't tried this mod myself so I can't testify but nearly everyone who has tried it have given it the thumbs up. Just look at the guy's feedback history.

However if you have yours tuned already...which optimises the air/fuel mixture at various RPMs...no point using this resistor... you might actually loose power.

[JezzaB]

Hi all,

I have a VT2 SS 6spd. I have the usual bag of tricks, edit, extractors/exhaust, OTRCAI, 3.9diff gears, ported throttle body. 234rwkw

Someone told me about an el-cheapo mod for modifying intake temp sensor by adding a resister to trick the computer to throw in a little more fuel/timing etc. Apparently its like $10 worth of stuff.

Does this mod work, will it cause harm? Does anyone know how to do it. Im not really technically minded, so could someone explain how to do it and what parts I need.

Your help much appreciated..

All the mod is, that you are unplugging the IAT (intake air temperature sensor). Which is actually a thermister, which means that it is a resistor that changes its resistance depending on the temp of the air coming in.

You simply replace it with a resistor that would simulate say 10oC. So your car thinks its 10oC, adds more timing and fuel for the "colder" air.

I tried it ages ago. Added a little timing but used a ton of fuel and didnt really feel any huge gains. They sell flashy ones on ebay but all they are inside the box is the same as this, a 5c resister from Dick Smiths.

Hope this helps,

Jez

[Shmacky]

Ok... explain how this resistor could blow up your engine? lol.

Fair enough, but it's obviously there for a reason.

Didn't a 2 cent washer (or similar) fail, leading to the destruction (read, one massive fireball) of a NASA Space shuttle??

Shmacky

[HRT Stroker]

These sort of "tricker" mods were popular before LS1 Edit......welcome to 1999......

Given the availability and relatively cheap cost of a tune, why would you want to risk bodgy electronic work arounds????

Do it right the first time and reap the benefits.

My 2c.

[Beej]

Ok... explain how this resistor could blow up your engine? lol.

As stated by others, by "fooling" the ECU into receiving an air intake temp that it's lower than the air being drawn in really is, may result in extra timing being added as well - if the actual air intake charge is in fact hotter, added timing advance may cause detonation. Severe/prolonged detonation CAN damage and possibly destroy your engine. The knock sensors MIGHT save you, but it depends on how much their impact has been disabled by the after market tune.

Cheers,

Beej

[VT GEN3]

How do you know if there is detonation. I tried the mod and the car goes quite a bit better with it to be honest. I just dont know if its pinging or not, doesnt appear to be, cant hear nothing.

How do you know if its pinging?

[VX_SS_II]

Personally, I wouldnt try it.

[michaels1v8]

Mate if your happy with it then that is fine. I feel an edit would do much more for you though and it is proven safe. Personally I would not try tricking the sensor, I dont see the value in it when an edit could net 15+ more rwkw at what is a reasonable price

[VT GEN3]

yeah i already have an edit done, but it seems to go better with the resiter tricking the IAT. If an edit maintains its timing then what would this mod do, just richen the fuel mixture?

But there would be no risk of detonation or pinging would there? as the timing is set by the edit? im no expert guys, so your help is appreciated. seat of the pants, ill tell you the resistor seems to work.

its a 3.3ohm 1 watt resister. 10 centrs from Jaycar or dick smith.

A friend of mine asked me to try it. Dont know if ill leave it on as i paid good money for the edit, but ill tell you it definately goes better with it.

[Tommy]

Edit does not maintain the timing.
That's the thing. When you lie to the computer about any input, be it air intake, water temp, Air Flow, the computer will use different (wrong)corrections to work out timing and fuel.
SO if the PCM thinks its 10 Degress intake temp, but it is really 50 degrees, then the PCM runs timing and fuel to suit 10 degrees air temp. WHich may cause detonation. Depends on a million factors.

You would be better to change the PCM so it does not correct so heavily as air temp rises, but these corrections are their for a reason.

If its going better with this mod, you need to revisit your tune on a dyno.
Technically should be able to make just as much outright power without lying to the PCM.