To Tweak or not to Tweak

[satanic]

Hello everyone...

I have a little bit of an issue here; to do with the R34 GTT and its performance (general running, and not power). It's an Tiptronic Auto.

My main issue is the fuel economy and the next issue is the power...

Now, many of you have suggested getting an aftermarket management system such as the SAFC II or the PFC (seems to be top choice). However...

My mechanic said it would make close to no difference in terms of better consumption or performance - is this true? or is it bullshit?

Secondly, since I have the Tiptronic Auto, which management system would work? Again I've been told several stories here: some say you need a piggy back system, others say stand-alone works just as well. What does work, and which one is ultimately better?

Your godly advice is very very much appreciated.

NOTE: In the not so distant future, the o2 sensor, oil filter will be changed as well as adding injector cleaner - in a bid to jack up fuel economy numbers.

[Beer Baron]

you cannot use a PFC with an auto so that rules out that choice for you.

[WazR32GTSt]

My mechanic said it would make close to no difference in terms of better consumption or performance - is this true? or is it bullshit?

well... technically its wrong but what he is saying is what happens in the real world

let me explain...

skylines run rich... right? so with an aftermarket mnagement system you will lean it out and make more power at lowe rpm so theoretically you will save on fuel

BUT... what do you do when you have more power? you use it! so as a result of having the aftermarketmanagement system you give it that little bit more which makes the theoretical fuel economy saving mean nothing.

Warren.

[satanic]

OMG it makes so much sense now... so all those products claiming to conserve fuel and increase power is just another debt trap for people to keep on throwing money into their Skylines!

[Cubes]

The only way the aftermarket management (not safc) could improve fuel economy is to slightly lean it out furthur than 15:1 on light load and cruise. Also extend how long it stays in closed loop mode. Play with ignition timing at light load and cruise.

Together it all makes a little difference but not much. If your not getting over 400km's per tank easily then something is wrong.

Pull the injectors out get them cleaned, check for airleaks, check compression etc and replace the 02 sensor.

Do the cheapest or what appears to be the problem first.

i.e if its idling a little rough clean the injectors.