Power FC Idle quality under electrical load

[Emre]

According to the AP engineering site, the difference in lag between the stock RB26 and Sard 700cc injectors are about +0.22, but my car seemes to behave much better if i set it at +0.50 or even +0.60.

EDIT: Fixed the link.

[Steve]

Merli, goddamit, I was keeping them a secret:(

Dean, you could buy the D Jetro, and I will swap you:)

Emre, that is the top feed version of http://www.ap-engineering.co.jp/el/inj_side.htm which states the difference to be 0.06 in my case. I will give it a go again with more than I wound in last time and see how it goes, cheers.

[Steve]

Just noticed too, that the impedance of the injectors (gtr to sard 700) is out by 0.3 ohms, would this have a bearing on the lag, as there is a bit more difference between mine and the stock injectors 11.5 to 14 ohms?

[BOOSTD]

There is no D Jetro version available for the RB25DET =(

[mist]

try testing your AAC as per engine manual... mine was shot & used to have hunting problems when air-conditioning was switched on.

[EnricoPalazzo]

Are u sure, im positive i saw a d-jetro for sale on yahoo auctions japan for rb25det. Hmmmm

[RNS11Z]

could it be the tps switch?

[Steve]

mist, how do you check AAC valve? I dont have a manual. I have pulled it off and cleaned it, and its seems to be in good condition, but it would be nice to run a check.

Emre, I ended up adding around 0.30ms extra in the injectors, and still didnt get it to work quite right, but throtle response is improved:) cheers.

RNS11Z, definately not tps, I have already checked the voltages and its all good - thanks for the suggestion none the less.

I fitted some new plugs, as it was taking longer to start on the cold morning, so I thought I would try some ngk 7s (had 8s). I think I found the problem - the old plugs were gapped between 0.5 down to 0.3mm! the 0.3 was in number 6 and was pretty carboned up. The guys who put them in didnt gap them, which is fair enough as they are supposed to be pre-gapped - but it was pretty obvious to me as soon as I started pulling them the gaps were way to small.

thanks for all the help so far.

[Emre]

WOW... 0.5 to 0.3mm in the 8s... How much power are you running...?

I don't think any plug in the market comes pre-gapped to those measurements.

From memory. you are running around 290rwkw, 7s gapped at 0.7mm would be a perfect choice IMO.

Increasing cylinder pressures is the best way to keep your plugs in good shape. Give the car a spirited drive around the block regularly for this reason alone. If you find that you are tootling around to work and back all the time, even the 7s will start fouling quickly.

[Busky2k]

Emre, I've been running 7s for the last 9 months, and they havent even been close to fouling, and I do city driving only really...

[Emre]

Emre, I've been running 7s for the last 9 months, and they havent even been close to fouling, and I do city driving only really...

What am i supposed to make of this post.

I wasn't suggesting you can't use 7s in city driving. I have been running 7s for 3 years and they haven't fouled yet.

Here is the point : If you get into the habit of getting to work and back like Miss Daisy and keep your car off boost, colder plugs will start fouling. Giving it WOT on regular basis will help keeping your plugs in good shape by clearing the fresh soot of.

[Steve]

making a bit over 300 rwkw, I was hesitant to run 8s, as I thought they may be a bit cold. OK in summer, but with the cooler weather, they dont seem to like it as much. They looked ok, except for 6 which as 0.3mm - that was fully black. And I agree completely about giving the plugs a good clean from time to time;)

[Steve]

Just checked on a mates car who has 550cc sard in an S14, the injector lag was +0.08. This car was set up by a jap mechanic and runs well, also has the same cams as mine.

I had to dump in a fair bit of fuel, but now the car is idleing perfect under EL and throttle response is crisper than when I had +0.38 ms.

Thanks heaps for all your help:)

[Bl4cK32]

Just remember all the settings - WRITE EM DOWN STEVE! - for when i come round with my annoying problem Steve:)

[Steve]

the settings are safely sitting in my power fc:)