Dirty Vegas

iTrader: (12)

Took a video, car almost completely dies on the initial hit.

http://www.youtube.com/watch?v=VvruvQPCsm8

Doug G

how was it purged ?

or was it ?

Dirty Vegas

iTrader: (12)

Purged through the motor in the pits.

ryarbrough

iTrader: (18)

How long are the lines from the noids to the jets? What was the pressure like? What jets? What was the timing like? Describe the activation system? Are you sure its lean?

Dirty Vegas

iTrader: (12)

Lines from the noids to the plate is about 24 inches on each. It will be a couple days before I can get an exact measurement, but it's whatever lines come with a new NOS plate. Pressure was right at 1000. Jetting was NOS listed jetting for a 100 hit, so .051 NOS, and I can't recall fuel at the moment. Activated by a push button, timing at 27, narrowbands showed lean, didn't have the wideband with me.

ryarbrough

iTrader: (18)

What is base timing? Can you throw a shorter nitrous line and a purge solenoid on it? DEFINATELY don't trust the narrow bands and be weary of the wb. They read O2, not fuel. If the car is pig rich it can read lean.

Dirty Vegas

iTrader: (12)

Timing is at 27 the whole way down the track. What should I have for an ideal line length? Have a purge, just haven't tossed it on yet.

ryarbrough

iTrader: (18)

By base timing I meant NA timing. Try the purge first. Ideal line length is as short as you can get them.

Dirty Vegas

iTrader: (12)

Timing was the same on spray and na. I've never pulled timing for a small hit. Plugs looked good after the pass. They were fresh before the pass.

ryarbrough

iTrader: (18)

What do mean by good? I don't want to sound like an ***, but even though I've seen you on here a bunch I don't want to assume. How thick was the fuel ring and what did the timing mark look like. Chances are that wont tell you anything anyway since you kept in it for the rest of the pass.

Nitro Dave's Nitrous Outlet

iTrader: (25)

What all is done to the car mod wise?

Most common for a lean stumble other than tuning issues are..
Not enough fuel pump.
Cloged fuel filter.

Dave

minytrker

iTrader: (13)

1,000 is a little high bottle pressure, try 950

27deg is to much timing for a 100 shot

narrowbands CAN NOT be used to tell you anything at WOT

Dirty Vegas

iTrader: (12)

By good, I mean they looked just like they were installed. No visible detonation, speckling, discoloration of any sort. Porcelain was clean, timing mark was right, could actually use a degree or two, fuel ring was right. So I guess that means I'm in the clear the rest of the way down the track.

Dave, it's a bolt on car. Lid/headers/ls6 intake, ls6 valve springs, stock heads, stock cam, stock bottom end. Fuel filter has less than 50 miles on it, and I'm running a Walbro GSS341 in tank. Fuel pressure is usually good, and I didn't see the gauge when this happened. It was good the rest of the way down the track.

Nitro Dave's Nitrous Outlet

iTrader: (25)

What spark plugs are you running? What is the gap?

You need to watch the fuel pressure gauge to eliminate that possibility. With what you have and a 100 shot you should be fine but the pump could be weak etc.

If the fuel pressure is not droping then we can talk about shortning the hose from the fuel solenoid to the plate.

Like suggested above you need to be removing about 4 degrees of timing.
Put a wideband in the car the narrow band readings will not help you.

Dirty Vegas

iTrader: (12)

It was a hair under 1000psi on the gauge. I really don't think that's the culprit, or even a factor.

Plugs say timing isn't bad. Looked like it could actually take an extra degree. I'll get pics of them next time I'm at the track.

I agree with the narrowband statement. I'm not trying to use them for tuning. I have a wideband for that purpose. I'm just saying the HPT log shows them going from .910mv to .038mv in 2 frames. It's still useful data.

minytrker

iTrader: (13)

I have never seen a LS1 want 28-29 deg of timing on a 100 shot. Many dont want that much na. I think you are miss reading your plugs.

Dirty Vegas

iTrader: (12)

BR7EF gapped at .030

Wish I could log fuel pressure through HPT...

I'll try less timing and report. I have a wideband, just need to remember to bring it with next trip.

I'll give you guys a call tomorrow to get this sorted out. I'm tired of this working like crap. I really want to go back to a dry kit at this point.

Dirty Vegas

iTrader: (12)

The line was right at the middle of the bend. I thought it was supposed to be more at the top of the bend? Is that wrong?

Nitro Dave's Nitrous Outlet

iTrader: (25)

Open up the gap on those plugs to about 34. That gap is to tight for your combo. (Could or could not be an issue)

We need to varify fuel pressure. Even it its a temporary test gauge. We need to find the issue and fix it before you hurt something.

First we need to determain is it a lean issue or a lean spike. While we are problem solving go ahead and put another two pill sizes bigger on the fuel side.

Go out somewhere you can just briefly hit the car and watch a gauge.

If the gauge stays solid and the wideband log shows a lean spike that then richens up you need to shorten the hose from the fuel solenoid to the plate.

Fix the plugs gap before doing anything.
Dave

ryarbrough

iTrader: (18)

Middle of the bend is ok, but leaning towards aggressive for a stockish setup... you aren't going to lose enough power to make a difference by taking a degree or two out.... I still don't think that's the problem though...