Does this C7 Dyno Graph Look Weird?
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Teching In
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Thread Starter
Teching In
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I'm thinking it may have just been lean and making big power and then when it fattened up to a safe level it fell down. That sharp dip in power directly corresponds to when the AF went from ~13 to ~12.5 or so. It was hard to read the graph.
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Teching In
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It looks very sharp to me too but the tuner said the TB was wide open the whole time. Maybe it limited torque by some other means?
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Teching In
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I have no idea why it would take so long to richen up on spray
I haven't sprayed it on the street I only use nitrous at the track, I haven't been to the track since the dyno I was going to go tomorrow.
On motor it drives pretty good, the part throttle shifts are too harsh for me I'm hoping to get those softened back up to stock, but WOT and stuff it seems to pull good. It smells a little rich at idle but there's no cats so whatever.
Teching In
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From: Charleston, SC
That's sometimes from the NOS pressure spike when the solenoid opens. Very common in systems that use a purge and an on/off opening switch. Not purging can reduce those spikes a little but gives a softer "hit" which most people don't like. It then richens up as the pressures normalize and taper off.
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Teching In
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That's sometimes from the NOS pressure spike when the solenoid opens. Very common in systems that use a purge and an on/off opening switch. Not purging can reduce those spikes a little but gives a softer "hit" which most people don't like. It then richens up as the pressures normalize and taper off.
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Teching In
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I wonder if it being lean down low made it knock and the timing retard just stayed in place for the rest of the pull?
How can I richen it up off the hit? That isn't a lean spike (to me) its several thousand RPM of being lean.
How can I richen it up off the hit? That isn't a lean spike (to me) its several thousand RPM of being lean.
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Teching In
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This is the AFR on motor
Still takes a little bit of time for the fuel to come in even on motor.
I'm curious if making the nitrous pulls in 4th gear was a mistake, the pulls only lasted like 3 seconds total.
I also don't spray out of the hole at the track, it'll spin. I let the car shift into second and then turn it on, I purposely don't purge so it doesn't knock the tires off.
I'm thinking by then it will already have pulled through a gear and the fuel should be there, I'll just make sure to have some 110 in it or some Torco, all these dyno pulls were on 93 pump.