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12.8@110mph, (log/slip inside), ignition problems... :(
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08-29-2012, 09:24 PM | #1 |
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12.8@110mph, (log/slip inside), ignition problems... :(
I went to the dragstrip a few nights ago chasing a mid 12 but was dissapointed again Still, ran my best mph to date, I guess.
My mods: Procede rev3 Catless downpipe Vanguard V2 exhuast 4 gallons E85, rest 93 octane Shell I was running map 1 with boost upped to 16psi. I realize now that not running map 2 may have left some power on the table.... the open loop ignition for map2 shows quite a bit of advance over map 1. That being said, in 3rd and 4th gear I'm maxing out timing at 3.5 degrees (NOT GOOD). I have a stock FMIC and my IAT's start at 117F in the beginning of 3rd to 145F at the end of the strip in 4th. The procede does not start pulling timing until 158F. Is this the DME retarding ignition because of IAT? Does anyone know what those thresholds are? |
08-29-2012, 09:29 PM | #2 |
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Perhaps it's just too much boost for stock FMIC... even with E85
My first run of the night was a 12.8@108mph and ignition timing looked to be autotuning upward... it got up to 6 degrees at the end of the pass. On that run, I peaked at 15.9psi when IAT's were 131F, and was still in the high 15psi's at 140'sF. In my glory run in the first post, it looks like a get a pretty significant timing drop at 16.8psi, even with a low IAT (relatively) of 126F. I'm not sure an upgraded FMIC will help any of this... I'm afraid it's probably meth or nothing I really didn't want to run meth. |
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08-30-2012, 05:50 AM | #3 |
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One thing that is killing you is not shifting at the optimal shift points. Try shifting at 5.5k. For the quarter mile you are blowing just hot air after that as your turbo is out of the efficiency range. You are significantly heating your ic up with that bright red snail
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08-31-2012, 12:39 PM | #4 |
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I'd really like to see a dyno of 1-4th gears to see where shifting at 5.5k puts you in the next gear.
I think we may be forgetting to factor in the torque multiplication of the lower gears. |
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08-31-2012, 01:06 PM | #5 |
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08-31-2012, 01:44 PM | #6 |
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I agree with above, your holding out too long to shift. 800rpms may seem like they go by quick, but add the torque and power lost from the heat at those rpms and youll shave a little time.
Also I know it doesnt affect your overall time or speed, but were you sleeping in the car? |
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08-31-2012, 02:22 PM | #7 |
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Good one...
RT has nothing to do with my slip and I'll be damned if I'm going to blow a launch (which is tricky enough on street tires with a 6MT), in order to be first off the line My best is a 1.90 on these tires, which still wasn't optimal... these PSS's have a 1.8 in them, I'm confident of that but will take a bit more concentration and a bit less nerves |
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08-31-2012, 04:24 PM | #8 | |
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Quote:
I used eyim1988's dyno results since we had the exact same mods (E85, dp, procede). It tells me that optimum shift points for my car as-is is redline in 1st gear, 6000rpm 2-3, 5600 3-4, and 5600 4-5. I was definitely shifting 2-3 around 6500, and around 6000 in 3-4, 4-5. Time to head back to the track!! |
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08-31-2012, 08:53 PM | #10 |
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I have a fmic now and u don't really feel any power difference. But I can do back to back runs now without major power loss
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08-31-2012, 11:02 PM | #11 |
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Yea, I'm not sold on the FMIC... I've seen plenty of single gear pulls stay under 115F, but ask someone to log a 1-4 pull and they are still above 130F at the end... it may recover faster, but in drag racing terms that doesn't matter.... I can just sit in the pits for a few minutes and get the same result.
I'm trying to plan a trunk mount meth kit, but it's so expensive to go Shiv's route vs a less civilized system.. i'm sure I'll end up biting the bullet but it's going to take some convincing |
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