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my car feels slower than stock, i dont know whats wrong i think its the afc, at around 5000 rpm it feels like i hit rev limiter and it does not move,, i think it could be timing related i dont know, my setup nissan t25 or t28 dont know,
dsm 450's22
std manifold
2.5 inch down pipe
v-afc set to specs in the faq
all help will be appreciated :'(

get your hands on a wideband

ill try, i dont know what it could be

Double check your settings. Assuming your VTEC cross over point is about 4500-5000 RPMs, it sounds like your wide throttle settings need adjustments.

but i used the one in the faq

Quote:

Originally Posted by 9tray turbo

but i used the one in the faq

The FAQ setting is a start to understanding how the VAFC settings should be done. I had one before and below is how I set mine. There are eight RPM and fuel setting points.

NEP:LVT(RPM) NEP:HVT(RPM)
1000 5000
1500 5500
2000 6000
2500 6500
3000 7000
3500 7500
4000 8000
4500 8500

VTEC crossover point was 4800RPM. I used to experiment with different crossover settings to see which one give a better transition to VTEC.

Below are the fuel settings for each RPM. Based on your setup you might have to increase the numbers (reduce fuel) or lower the numbers (increase fuel).

Narrow Throttle Wide Throttle
1000 38 5000 35
1500 39 5500 35
2000 39 6000 34
2500 35 6500 34
3000 25 7000 34
3500 36 7500 34
4000 36 8000 34
4500 35 8500 34

I hope this cure the problem you have.

Quote:

Originally Posted by StanB

Quote:

Originally Posted by 9tray turbo

but i used the one in the faq

3000 25? why you put to much fuel in this rpm? hom much psi in your gas rail for injectors? please let me know.

Quote:

Originally Posted by dv74boost

3000 25? why you put to much fuel in this rpm? hom much psi in your gas rail for injectors? please let me know.

It was just weird to me. It's the only way the tuner could get the AFR within an acceptable range. The fuel pressure gauge was at about 34-36 psi with the vacuum hose connected to the fuel pressure regulator. I dont know what your setup is, so start with less fuel (higher number) and see how the car performs. Remember to retard the timing also. My timing was set at about 8 degrees BTDC. With the settings above I made 225WHP and 211FT Torgue @ 15PSI. If you search the forum you'll find my setup. Right now I am running Uberdata.

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