ALKY and launch

[larrym]

When you guys are building boost do you have your ALKY starting to spray after you leave or while staged.
Mine starts spraying at 5psi full duty cycle at 22 psi this set up works good on the street could it hurt my launch if I'm trying to leave at 8-10 psi?
I can adjust it easily to start at 8psi and drop the full duty cycle to 18 it reaches full boost in the blink of an eye leaving at 8 psi.

 

[murphster]

For safety you should have it start trickling in while staged so that its ready to go once you leave and the boost comes up in that blink of an eye.

Lets say you have a very small leak that you are unaware of. You primed the alky while in the staging lanes (you do prime it, right? A must). At the line you stage at 7psi but have the turn on at 8psi. In the meantime your alky line lost pressure from the prime because of the small leak. You launch and go to 20psi boost almost immediately but your alky pressure is delayed a little because of the lost line pressure. You now barely have any alky for the first second at 20psi boost before the full alky comes in. You blow a head gasket and wonder WTF happened? This also happens a lot of time on the street on alky when people just stab the throttle after not having primed the alky recently instead of just rolling into the boost.

My last time out I had about 75psi of alky while staging at 13psi boost before launching. At 8psi boost I had about 40psi of alky while building boost on the transbrake. I do have the fuel trimmed so it doesn't go rich in this area and you need to account for this. 1.33 60ft.

 

[larrym]

Thanks Murphster sounds like solid approach
I will tune some fuel out at high load low rpm with the Gen2 and see what it's like. It leaves pretty good no 60' times yet there is a slight pause when I let off the 2 step but then it leaves.
https://www.facebook.com/lmyhres/posts/10207346661533111

 

[aminga]

I have mine turn on at 14 PSI of boost and it is at full pressure by 20 PSI. Usually it doesn't come on while staging or building boost.

 

[TT/Ameasap]

I have always had turn on at about 5psi and never had a problem with being too rich out of the hole. Isn't the chip made for alky anyway?
It doesnt matter if the wheels are turning or not. The same amount of air and fuel are being burned. Your just holding the wheels locked or tranny if you have a tranny brake 1st reverse.

 

[larrym]

I know that the TT chips compensate the fueling and timing when set up for ALKY
I'm not sure how the Extender G for the Gen2 is set up, it's very tunable and I will let you know how I do my plan is to take it out and foot brake it on the 2 step see where the AFRs are with boost and dial in the fueling at the RPM and load point I'm seeing I will probably target around 10.9 so it's safe. I will leave the ALKY set to come on at 5psi and let the wide band correction keep it close the correction is set to come on at 3200 rpm above what I launch it at. (2 step is set at 3000)
See any flaws in my approach ?

 

[TT/Ameasap]

Sounds good.
Just a tid bit tho...At your power level, I used to run lean and mean. that always netted better E.T. and 60ft's.
Let us know how you do.

 

[larrym]

Thanks I will post my results. When it comes to lean I'm a coward...

 

[TT/Ameasap]

Put a new set of plugs in right before a pass. Pull a few right after you get to the pits and see what the motor is really telling you. Everyone should do this at least once to see if your numbers are accurate. Back in the day, I found my car could run 710-720mv on the SM through the traps. 11.30's with stock stuff and ta49 turbo. It pays to check your plugs.

 

[larrym]

So left it alone alky coming on a 5psi our annual race was this weekend left at 8psi on 9" slicks 2 step at 2900 ran an 11:36 at 115 personal best no cage so I had to slow it put my nittos back on set the 2 step to 2700 launched with 3lbs of boost 1.69 60 116.5 mph with 11:39 so I was done for the day but grinning from ear to ear.