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Discussion Starter #1
Took my car for its first power run the other day.

S2 RB25DET
K n N filter
Standard Turbo
Huge FMIC
Turbo Elbo
Full 2.5 inch exhaust inc downpipe
Walbo Fuel Pump
Standard ECU
SAFC
AVCR





Very happy with that for the boost level. mmmmm maybe too good?
So for standardish boost i have gained 60 FWBHP over standard.

Anyone know how to check the validity of the results? eg revs could be out seeing as the opperator stopped before 6500rpm according to the chart.

Any comments on fueling etc welcomed.

Cheers
 

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Discussion Starter #5
Make it a little richer from 3500-4800 ish and the torque curve will be smother!
Please explain how that makes the torque curve smoother? I trust that it will work but just trying to understand why.

Are we richening the mix to gain more torque in that area to fill in the flat in the curve? The second peak on the torque graph is due to the variable valve timing kicking in. is it anything to do with that?

Thanks
 

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Yes the hump is when the VVT switches off. The Nissan VVT work in reverse as its more for emissions than power.

The reason I say put a little more fuel in is because at the point of max boost you are running the least amount of fuel. If it has a little more fuel it might make a little more torque and make the hump smaller.

Richard
 

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Could the dip possibly be due to a hint of wheelspin?
I also think your strong horsepower figure is partially due to the fairly high intake temp.shown on the graph
 

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b16 nyk
What do you mean? High temp would mean less bhp. The figure shown is about right for the mods, with the temp the car was running at the time.

Did they have a big fan in the dyno room?
 

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as damo says the higher intake temp the lower the power hence why when its cold our cars go soooo much faster
 

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Damo. What would happen to the hp figures if the probe is left hanging off the dyno rather than being heated up in the intake(or sat in a cup of warm tea!)?The slightly high IT34 figure shown with AT14 will certainly add a few horsepower on the graph

Speed33per; yes our cars do tend to make more power on cool winter evenings.The dyno is compensating for what it believes to be warm temps correcting the hp upwards slightly
 

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Damo. What would happen to the hp figures if the probe is left hanging off the dyno rather than being heated up in the intake(or sat in a cup of warm tea!)?The slightly high IT34 figure shown with AT14 will certainly add a few horsepower on the graph

Speed33per; yes our cars do tend to make more power on cool winter evenings.The dyno is compensating for what it believes to be warm temps correcting the hp upwards slightly
By about another 1% per every 3 degrees above 20c ;)
 

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Discussion Starter #12
cheers guys thats the kind of info im after:cheers:

So IT34 = intake temp
AT14 = Air Temp

????

There was a huge fan pointing at the car but bonnet was closed.

I could not tell you where the IT probe was on the run but in my S13 the under bonnet temps are very high and the bonet was down (not helped by my electric fan instead of viscus fan spinning all the time) so would not be supprised if that was correct if the probe was near the filter!! I take it should really be placed after intercooler into the system.

On the day it was very cold and so AT14 would seem correct.

So if the temps all seem correct does this not seem like higher than normal power figure for 0.65 bar boost with no tuned ignition timing and fairly rich AFR ???

I know i shouldnt really be complaining with the power figure but just trying to learn what i can from it.:cheers:
 

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Personally I think that's not a bad looking graph considering the stock ecu.With some form of ignition control,onather psi or so boost and possibly a hint leaner at the top end you'll make a few more bhp and it will drive much nicer

However, I reckon a ecu upgrade along with a decent intercooler(which you have) is almost mandatory on a gtst
If you've driven a Skyline with a well mapped power fc,you'll know what I mean
 
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