Alky Level ?

[3.8L V-8 eater]

Went to the track Friday night and on a couple of the passes I saw a little knock briefly and noticed the w/band went lean then back to normal..

My question is could the alky sloshing in the tank have caused this?? Did it drw air for a split second?? I still had alky up to the full line but did notice on the launch the low alky light blinked...After the pass checked the level it was at the full line so didn't fill it...Had my buddy do a pass in my car and same thing happened to him.....

 

[we4Mateo]

What full line? The tank should be filled all the way up. Especially when launching hard at the track. The full line, if you are using the factory coolant overflow, is marked for coolant, not alky.

 

[3.8L V-8 eater]

Ya it was on the full line that is marked on the bottle...So you think that was likely culprit went dry for an instant??

 

[we4Mateo]

Ya it was on the full line that is marked on the bottle...So you think that was likely culprit went dry for an instant??

Yep. You should never see the low light flash at the track.

 

[Boost231]

if the bottle is not 90% full i wouldn't run it down the track. i have also gotten the lean spike but the xfi corrected. Glad i had C16 in the tank

 

[3.8L V-8 eater]

Car was ok just seen the lean spike for an instance...1.2* of KR and car is fine.....Of all the locals I know who have TR's none run alky, so I'm trying to tune and learn as I go....

Just wondering how many are using the purple wire from the pac controller that delays the alky coming "on" for launching?? Don't have that hooked up, but I'am wondering if I should???

 

[Slow91z]

Just wondering how many are using the purple wire from the pac controller that delays the alky coming "on" for launching?? Don't have that hooked up, but I'am wondering if I should???

I don't know anyone that has hooked that up.

 

[TURBOPOWERED68]

Car was ok just seen the lean spike for an instance...1.2* of KR and car is fine.....Of all the locals I know who have TR's none run alky, so I'm trying to tune and learn as I go....

Just wondering how many are using the purple wire from the pac controller that delays the alky coming "on" for launching?? Don't have that hooked up, but I'am wondering if I should???

i don't but i might play with it since the Alky sprays while i am on the Two step.

 

[Razor]

Ya it was on the full line that is marked on the bottle...So you think that was likely culprit went dry for an instant??

Fill it to the top of the neck.
Another thing you can do is simply hit the test button after the burnout and make sure its fully primed. As you have a few seconds before staging.

 

[3.8L V-8 eater]

Fill it to the top of the neck.
Another thing you can do is simply hit the test button after the burnout and make sure its fully primed. As you have a few seconds before staging.

Julio, wouldn't the alky already be spraying if I build 5lbs of boost or more at the line?? If so wouldn't it be primed by the time I launch??

 

[TurboTGuy]

Julio, wouldn't the alky already be spraying if I build 5lbs of boost or more at the line?? If so wouldn't it be primed by the time I launch??

The test button is an easy and important step in the staging process and provides double assurance that alky is in the line.

 

[3.8L V-8 eater]

My real issue was trying to figure out why I had a lean spike half way down the track when the pump was fully primed and spraying...Leason learned I will keep the alky level filled to the top of the bottle and not assume it's ok because it's at the full level of the coolant line on the bottle....

 

[Razor]

My real issue was trying to figure out why I had a lean spike half way down the track when the pump was fully primed and spraying...Leason learned I will keep the alky level filled to the top of the bottle and not assume it's ok because it's at the full level of the coolant line on the bottle....

Could also be fuel level in gas tank.
If your not logging fuel and alcohol pressure.. then its all a guess.
Half way down the track would probably be fuel related. If the alcohol tank was the issue.. it would be right on the hit like 60 feet out. By the time the car is leveled off.. there would be no more issue.
I record pressures every run I make. It elimates the questions marks? But thats just me I also run a full gas tank and full alcohol tank.

 

[3.8L V-8 eater]

Had 3/4 of a tank of gas which i would think would be ok...I thought about that as well Julio...Car should have been leveled off that far down the track...The KR was at 96 MPH...Nothing to log alky pressure with, but do have a hood mounted fuel pressure gauge...Next time I go to the track I'm going to set the PL to start recording off the TPS signal vs me remembering to trigger it with the spacebar.....

 

[Razor]

96 mph I doubt its a slosh issue. Something else is going on. Bet its fuel.

 

[3.8L V-8 eater]

96 mph I doubt its a slosh issue. Something else is going on. Bet its fuel.

I think your right!! I did take some fuel out of it in all 3 gears 4.7% which could be the issue... The wideband however not got leaner than 10.6 and I would like to run a 10.8 to 11.0 AFR......What if i put the fuel back in and started to lean it back out with more boost???

 

[we4Mateo]

I think your right!! I did take some fuel out of it in all 3 gears 4.7% which could be the issue... The wideband however not got leaner than 10.6 and I would like to run a 10.8 to 11.0 AFR......What if i put the fuel back in and started to lean it back out with more boost???

That's a good way to do it if everything else is up to par.

 

[Razor]

I think your right!! I did take some fuel out of it in all 3 gears 4.7% which could be the issue... The wideband however not got leaner than 10.6 and I would like to run a 10.8 to 11.0 AFR......What if i put the fuel back in and started to lean it back out with more boost???

What you would like to run and what the car tells you it likes are two different things. Throw fuel at it and then once its running clean with zero knock.. then lean it out a little at a time and see if it picks up MPH.
My fastest pump gas customer runs 9.6:1 afr

 

[3.8L V-8 eater]

What you would like to run and what the car tells you it likes are two different things. Throw fuel at it and then once its running clean with zero knock.. then lean it out a little at a time and see if it picks up MPH.
My fastest pump gas customer runs 9.6:1 afr

I saw just 1.2* of knock, but I will put back in half the fuel I took out...I will move parameter 1 from 122 to 125 and log the pass and see how it goes....Going to the track tonight if it does not rain....