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None the less Tasos car does appear to have a few little issues. Cam timing and afr's. It shall be very interesting if fixing these issues drop power to whats considered normal levels.

If so well... It appears Taso has stumbled upon a cheap easy way to make excellent power. Do the old VL trick, throw it a tooth forward or back.

Taso, be sure to take note of what the cam timing was prior, if it drops power throw it back to the way it was and bath in the free power and share it with the rest of us SAU goobers. :D

I'm still going to call botched figures.

Skylines simply don't make alomst 200rwkw standard.

As I said before, when my car was stock, it was in perfect condition, and by that I mean perfect. Motor was 169psi across all cylinders and 2% leakdown which is on par to brand new.

Made 140rwkw with 10psi and a full exhaust and FMIC.

210rwkw with powerfc added and 13psi boost, and toluene.

Dyno Dynamics Dyno.

your car might have been as good as new, but 140rwkw with a full exhaust is considered a low figure :no:

My car got dynoed today before the PFC went in, and the afr's were 11:1...nice and rich just like a stock ECU should be.

So taso's car obviously has something thats causing it to have 13:1 afr's

The graph almost looks like it has been tuned that way. If so, then I hope they also backed the ignition timing right off. If this is done, and fairly low boost, it may not be that bad for the car. This is certainly why you are getting so much power, as there are great gains to be made when you run it leaner, however you have to offset the risks of pinging etc.

None the less Tasos car does appear to have a few little issues. Cam timing and afr's. It shall be very interesting if fixing these issues drop power to whats considered normal levels.

If so well... It appears Taso has stumbled upon a cheap easy way to make excellent power. Do the old VL trick, throw it a tooth forward or back.

Taso, be sure to take note of what the cam timing was prior, if it drops power throw it back to the way it was and bath in the free power and share it with the rest of us SAU goobers. :ermm:

Yea it will be very interesting. If I drop 20kW tho I reckon i will put it back to where it was as its not pinging yet. Only disadv is I'll have to use octane booster everytime i fill up jus to be sure. I wonder id leaving it as is and using a SAFC to richen it up a bit will make it still produce the same power?

it is true that dyno is only a tool for tuning, but none the less when there is such a large discrepency you shouldnt just generalise it like that and forget about it.

theres no need to be changing anything like your pump or FPR, why dont you instead *TEST* them. in one simple test you can check both, its called 'checking fuel pressure'.

any workshop with a dyno should have a fuel pressure gauge, get them to hook it up and run it on the dyno (workshop is useless for not doing it already). if fuel pressure isnt sitting at what is stock for RB's then it could be your FPR, if it holds pressure down low, but it starts to taper off up top, then thats indicative of a dying fuel pump.

being that the power figure is a little happy, the actual wideband meter may not be correctly calibrated either(ie useless workshop). solution ? goto another workshop and get a second opinion/another dyno run for comparison

Was wondering, could a faulty o2 sensor cause the car to run lean?

Yes. I would not usually say this but for the first time ever I saw a standard nissan ECU apply closed loop fuel corrections in open loop. If the tune is overly rich in closed loop then you could have negative LTFT number that are being applyed at open causing it to lean out. Whats the code on the ECU? The ECU is I saw this ocur on was MECR-212?

I'm only saying this if you are sure you've check everything else is sweet and you've exhausted every other option.

Edited by rob82
Yes. I would not usually say this but for the first time ever I saw a standard nissan ECU apply closed loop fuel corrections in open loop. If the tune is overly rich in closed loop then you could have negative LTFT number that are being applyed at open causing it to lean out. Whats the code on the ECU? The ECU is I saw this ocur on was MECR-212?

I'm only saying this if you are sure you've check everything else is sweet and you've exhausted every other option.

Interesting theory, ive never hear of this before. If ur talking about the code on the side of the ECU ill check it 2moro and post it up. I'll also check the fuel pressure on the next dyno run.

I highly doubt the dyno is wrong, coz every single person i've been in the car in says is feels like a mid 13sec car, and i havent told them about 190rwkW so its not biased.

In regards to what u said ROb, is there anyway of checking that this negative loop thing is happening on my car? And if so how did u guys fix it?

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