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Falls on face in between shifts

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Old Sep 18, 2013 | 01:43 PM
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Falls on face in between shifts

So I have this strange problem where my car falls on it's face when I shift.
I have enabled fuel cut on my P1000, yet it remains real rich and my boost plummets to 2 PSI in between shifts.
I can put the pedal to the metal and it jsut sits there...doesn't accelerate.
It is costing me about a second per shift in the 1/4 mile.
Other than that problem, the car runs like a top!
I have checked my coils, thinking one of the trailings might be dead, but that isnt the issue.
Anybody had this problem or know what would cause this?
Thanks!
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Old Sep 18, 2013 | 02:57 PM
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From: Floyds Knobs. IN
Map, logs, and dyno sheet please.
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Old Sep 18, 2013 | 05:32 PM
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http://www.idahorotary.com/chris.zip
No Dyno graph, but log and map
Whats a good throttle body? I think mine is worn out
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Old Sep 19, 2013 | 12:06 PM
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Disregard that map...I upped the wrong one...I will put the newest one on tonight
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Old Sep 19, 2013 | 03:12 PM
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From: Floyds Knobs. IN
Well, for one, you shift really slow. The two shifts in that log are about a full second.

Reason I asked for a dyno chart is to see where the actual power lies in the rev range. I'm guessing the first shift is the 1-2? RPM falls back to around 4500 after the shift. On the next shift it falls to around 5000. On a big turbo, if it doesn't hit full spool until 5k, you're going to have transient issues like this every time you shift.

You made the first shift at 7700 and the 2nd shift at 6500. Aren't you running a half bridge? Even if it's a street port, put your big boy pants on and rev it. A street port should make good power to 8500. Even if it falls off some, you may make big transient response gains by having the revs fall into the boost curve after the shift. A half bridge might make power up to 10k or more, that's where you'll want to shift.

Put it on a dyno and just get an idea of where it makes power. Then you'll know where you need to shift. It might even be a situation where you can go quicker with a smaller turbo that has better transient response.
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Old Sep 19, 2013 | 04:30 PM
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Hey Chris, My engine is not balanced or clearenced.
I have my shift light set at 8200 RPM.
I am trying to get the shifts ironed out...that's the whole point of this post...I don't shift that slow, it just looks like I do.
I have richened up the fuel during the primary stage from 0-3.2 PSI in hopes that will smooth things out.
Where I do the road stuff, I am very cautious and usually don't get past the middle of 3rd because there isn't enough room...guess I better go to the dyno.
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Old Sep 19, 2013 | 07:54 PM
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Thank you Sleeper7 for getting on track....basically the transition was too far apart.
Now I can shift faster!
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Old Sep 20, 2013 | 05:46 PM
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Yep! Thanks to Sleeper7, I have my mad shifting skills back yo!
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Old Sep 20, 2013 | 08:03 PM
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Id offer my two cents but I don't think it ever matters
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Old Sep 20, 2013 | 09:55 PM
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Originally Posted by silverfdturbo6port
Id offer my two cents but I don't think it ever matters
Sure it does! Did you look at the map?
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Old Sep 21, 2013 | 12:34 AM
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It wont let me view it.
Take a screen shot of your fuel and timing in 3d view.
What are you running your injector transition at?
Your car is a s5 t2 keg as I recall..?
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Old Sep 21, 2013 | 03:15 AM
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From: Floyds Knobs. IN
It's a zip file. Download it and then unzip it. Lets me view it.
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Old Sep 22, 2013 | 01:42 AM
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Does not work for me
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Old Sep 22, 2013 | 08:58 AM
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Meh... It's not my map. Still does it even with the recent changes....its a little better, but something changed.
It used to spin the wheels when I hit 2nd and 3rd. doesn't do that anymore.
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Old Sep 22, 2013 | 10:05 AM
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Looking at the video of my runs, I see clouds of white smoke in between shifts. Not burning the fuel. Got to be plugs or coils I'm thinking.
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Old Sep 25, 2013 | 10:00 AM
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Originally Posted by c. Ludwig
well, for one, you shift really slow. the two shifts in that log are about a full second.

Reason i asked for a dyno chart is to see where the actual power lies in the rev range. I'm guessing the first shift is the 1-2? Rpm falls back to around 4500 after the shift. On the next shift it falls to around 5000. On a big turbo, if it doesn't hit full spool until 5k, you're going to have transient issues like this every time you shift.

You made the first shift at 7700 and the 2nd shift at 6500. Aren't you running a half bridge? Even if it's a street port, put your big boy pants on and rev it. A street port should make good power to 8500. Even if it falls off some, you may make big transient response gains by having the revs fall into the boost curve after the shift. A half bridge might make power up to 10k or more, that's where you'll want to shift.

Put it on a dyno and just get an idea of where it makes power. Then you'll know where you need to shift. It might even be a situation where you can go quicker with a smaller turbo that has better transient response.

wow!
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