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Old Jun 7, 2010 | 12:18 AM
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Help me figure this out?

So I have had an issue with my new motor setup from the beginning. Seems when I get a good 60 I am holding on ready for a new best but I get a cut in 1st gear. Looks, feels like the car just shuts off. I have spent hours trying to figure this out but end up with no anwser. I thought maybe at first rev limiter but my logs show the cut well below the limiter. My latest thought (Barry Borders also) is fuel starvation. Is it possible to have this with out the motor going pop! Can a hard launch cause the pumps to grab air droping pressure for a moment? I only have this in 1st gear which would be the fastest acceleration.

Am I looking in the wrong direction?
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Old Jun 7, 2010 | 12:45 AM
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From: ya mums kitchen
i still think its a elec problem, something in the wiring somewhere could be honkey.
For a fuel cut to be so drastic as that you would have to be draining all the fuel in your rails asap, and you would see your a/f logs go off chops too, but it would be progressive in the a/f logs, as a sudden lean then rich situation i cant see coming from your pump

what ignition coils are you using and what boost levels is it running and what spark plugs are you using, and how old are the ignition leads
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Old Jun 7, 2010 | 03:42 AM
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From: Floyds Knobs. IN
Originally Posted by sk8world
So I have had an issue with my new motor setup from the beginning. Seems when I get a good 60 I am holding on ready for a new best but I get a cut in 1st gear. Looks, feels like the car just shuts off. I have spent hours trying to figure this out but end up with no anwser. I thought maybe at first rev limiter but my logs show the cut well below the limiter. My latest thought (Barry Borders also) is fuel starvation. Is it possible to have this with out the motor going pop! Can a hard launch cause the pumps to grab air droping pressure for a moment? I only have this in 1st gear which would be the fastest acceleration.

Am I looking in the wrong direction?

Certainly possible. Run the car with a full tank and see what it does. If it still does it then this is most likely not the problem. Installing a fuel pressure sender and logging that would be the best way to check though.
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Old Jun 7, 2010 | 04:45 AM
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Originally Posted by sk8world
So I have had an issue with my new motor setup from the beginning. Seems when I get a good 60 I am holding on ready for a new best but I get a cut in 1st gear. Looks, feels like the car just shuts off. I have spent hours trying to figure this out but end up with no anwser. I thought maybe at first rev limiter but my logs show the cut well below the limiter. My latest thought (Barry Borders also) is fuel starvation. Is it possible to have this with out the motor going pop! Can a hard launch cause the pumps to grab air droping pressure for a moment? I only have this in 1st gear which would be the fastest acceleration.

Am I looking in the wrong direction?
Before I sumped my tank I would have the same exact issue if I ran 1/4 tank or less. I would have to run at least 1/2 tank of gas. I'm almost positive that's your problem.

I also had a similar problem when I had a battery terminal loose, silly mistake but the ground would come loose on the launch.

Anthony
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Old Jun 7, 2010 | 09:41 AM
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Beef,
I run stock coils and 10mm magnecors, coils packs have been changed multiply times. The AFR's do go crazy, go from 11's straight to 19's then back and forth . Boost was 28psi and running the $$$ NGK's 11's.

C. Ludwig, Kinda my same thoughts on logging the fuel and filling the tank but it would cost me a billizion dollars to fill up in Q16.

Anthony, So how much trouble to sump the tank? I am guessing I would need one of those
A1000 pumps and a nice filter inline. Whats your set up consist of?

I should have my clutch in for this weekend and will put in all the q16 I have left (12 gallons) and try it again. Now I sure wish I was running e85, pumps 15 mins from my house.
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Old Jun 7, 2010 | 09:57 AM
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From: ya mums kitchen
yeh well you spark side of it definitely sounds ok but does it rely on just factory coils, its not enhanced with ignition boosters or anything like that cdi an stuff ?,
Not from personal experience but id want a bit more that stock ignition at high 20 psi boost as my tuner has talked about a few cases every now and again getting spark blow out at that level ,
But hears hoping you get it solved asap
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Old Jun 7, 2010 | 12:31 PM
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I have heard of a few making 800+ on stock coils and HKS Ign. Not saying I wont change coils soon. I am puting my money on the fuel pumps. Going to try and run 1/2 tank next time out.

Thanks guys and I will update this thread.
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Old Jun 7, 2010 | 04:52 PM
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Dude, if I try running less than 1/2 tank. Mine cuts out really bad too. Do you have the dual pump setup? Mine does...
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Old Jun 7, 2010 | 04:58 PM
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Originally Posted by sk8world
Anthony, So how much trouble to sump the tank? I am guessing I would need one of those
A1000 pumps and a nice filter inline. Whats your set up consist of?
My old FD (Blue one), I had a ghetto sump. We pulled the tank, washed it really well, welded two -10 bungs on the back/bottom of the tank. Boom, ghetto sump. Worked great. I ran one A1000 pump and aeromotive filter.
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Old Jun 7, 2010 | 05:07 PM
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Originally Posted by Viking War Hammer
My old FD (Blue one), I had a ghetto sump. We pulled the tank, washed it really well, welded two -10 bungs on the back/bottom of the tank. Boom, ghetto sump. Worked great. I ran one A1000 pump and aeromotive filter.

I will do a sump set up next just not sure if I want to try it now or what till winter. I am running Ernie's old twin supra pump-pull out.

So I guess I will runn a -10 to a block going to each of my -6's . What about my return line? Were did you guys run that to tank?
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Old Jun 7, 2010 | 05:45 PM
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Originally Posted by sk8world
I will do a sump set up next just not sure if I want to try it now or what till winter. I am running Ernie's old twin supra pump-pull out.

So I guess I will runn a -10 to a block going to each of my -6's . What about my return line? Were did you guys run that to tank?
Oh forgot about that, we put a bung of the top front of the tank for the return.
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Old Jun 8, 2010 | 12:17 AM
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Originally Posted by sk8world
C. Ludwig, Kinda my same thoughts on logging the fuel and filling the tank but it would cost me a billizion dollars to fill up in Q16.

Anthony, So how much trouble to sump the tank? I am guessing I would need one of those
A1000 pumps and a nice filter inline. Whats your set up consist of?

It's not a lot of trouble at all. I just drilled three large holes and then welded the sump on to the existing tank.

I run the old Bosch style pumps, I have 2 of them below the tank. They are about 8 years old and still going strong.

As for C16, I always run about 6-8 gallons but I drain it right after and keep it in the containers for the next event. I always drain the pump gas first as well before I add any C16.

Before you even sump the tank, why not go back to the track with 1/2 tank of C16. If that solves the problem drain it back into the container and keep it for the next time you run again.

Anthony
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Old Jun 8, 2010 | 01:08 AM
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Get the sump that has a drain on the bottom, makes swapping fuels so much easier.

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Old Jun 8, 2010 | 07:13 AM
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I had the same issue Anthony had. Until I get a fuel cell or a sump, I have to run 10gallons of fuel to be safe. Extra weight is worth the insurance, imo.
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Old Jun 8, 2010 | 07:30 AM
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My vote would be for the simplest and most inexpensive route; Hyperion's sump cover and E85.

Has anyone tried it for drags?

Barry

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Old Jun 8, 2010 | 12:30 PM
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Originally Posted by AnthonyNYC
Get the sump that has a drain on the bottom, makes swapping fuels so much easier.

Anthony, were you get this from? Jegs-Summit?
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Old Jun 8, 2010 | 01:00 PM
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Originally Posted by sk8world
Jegs-Summit?

Yep. I might have someone interested in trading a sumped tank for your stock tank.
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Old Jun 8, 2010 | 02:15 PM
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Originally Posted by C. Ludwig
Yep. I might have someone interested in trading a sumped tank for your stock tank.
Let me know and send me pics.
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Old Jun 14, 2010 | 08:09 AM
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From: Floyds Knobs. IN
Sent my buddy a link to this thread and told him to contact you. He's in Louisville so not sure how you guys would work the swap.
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Old Jun 14, 2010 | 10:44 AM
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Originally Posted by C. Ludwig
Sent my buddy a link to this thread and told him to contact you. He's in Louisville so not sure how you guys would work the swap.
And here I am. I don't have a clue on the best plan for getting this done. Let me know what you have in mind on the logistics and we can try to sort it out.
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