1/8th mile shakedown

[Aeroking]

I went to the local 1/8th mile for some shakedown passes on my new build. Mods in sig, no meth hooked up.

Problem: no spool at launch, Solution: higher stall.

Best pass was:

60' = 2.16
330' = 5.745
1/8 = 8.65 @ 85.4

That run i sat on the converter for a few seconds, and left at 2psi (breaking the tires loose when i launched).

Its a 2800 9/11, and it stalls around 2650~2700. At about 3500 in 1st, i was at 10psi, and by 4500 it was at 20psi, and held thru 3rd gear

pulled strong once it hit 20psi, but before that it was dogging it. It shifted to 2nd about half track, and ran thru 2nd gear and most of third before the line, so its got alot of top end. Just gotta spool it better for a good launch.

 

[91blazins10]

Re: 1/8th mile shakedown

hmmm my stock turbo typhoon ran a 8.510@79.86 I think we need to work on your tune a bit.

 

[SY2932]

Re: 1/8th mile shakedown

hmmm my stock turbo typhoon ran a 8.510@79.86 I think we need to work on your tune a bit.

HATER

! My best ET in the furlong when I was stock turbo was 7.901 @ 87.21 with a 1.711 60'. GREAT to hear that you are on your way to getting things dialed in ! That 60' time looks like most of my reaction times, I'm usually in the 1.5 to 2.5 second range. I don't leave the line until I'm ready. You should do the same too unless you are bracket racing

...

 

[Aeroking]

Re: 1/8th mile shakedown

my RT on each run were 5+ seconds, sitting there trying to spool the turbo. but nothing.

the 2.1 60' was the only run were i built boost (2psi). the rest of my 60's were 2.4s

 

[JSM]

Re: 1/8th mile shakedown

The MPH is telling your making power for high 7 run, as mentioned gotta get out of the hole, get it to spool better.

 

[Aeroking]

Re: 1/8th mile shakedown

if i get off the line better, that would increase my MPH too, wouldnt it?

 

[JSM]

Re: 1/8th mile shakedown

yes

 

[dgoodhue]

Re: 1/8th mile shakedown

I went to the local 1/8th mile for some shakedown passes on my new build. Mods in sig, no meth hooked up.

Problem: no spool at launch, Solution: higher stall.

Best pass was:

60' = 2.16
330' = 5.745
1/8 = 8.65 @ 85.4

That run i sat on the converter for a few seconds, and left at 2psi (breaking the tires loose when i launched).

Its a 2800 9/11, and it stalls around 2650~2700. At about 3500 in 1st, i was at 10psi, and by 4500 it was at 20psi, and held thru 3rd gear

You will need more stall. A 74 is big turbo. Even with a good top end, I would guess your truck might hit 110mph in the 1/4 mile with your time posted (low 13 sec ET's) I would expect 125+ mph with a 74 an your mods.

As a temporary fix, you could try leaning your truck out at transisiton from boost to vacuum and low boost level to help spool up.

 

[91blazins10]

Re: 1/8th mile shakedown

Well Brandon im off a few days in august, we could probably swap out the converter in a few days. Maybe Mike can even stop by and we can swap out it his motor so he doesnt smoke us out anymore :rotf:

 

[Aeroking]

Re: 1/8th mile shakedown

Well Brandon im off a few days in august, we could probably swap out the converter in a few days. Maybe Mike can even stop by and we can swap out it his motor so he doesnt smoke us out anymore :rotf:

i'm gonna hold off for now. swapping it is no big deal. i'll see if i can remedy it some other way.

i'll play with the tune abit, and see if it helps when i run at the Extravaganza.

 

[Aeroking]

Re: 1/8th mile shakedown

You will need more stall. A 74 is big turbo. Even with a good top end, I would guess your truck might hit 110mph in the 1/4 mile with your time posted (low 13 sec ET's) I would expect 125+ mph with a 74 an your mods.

As a temporary fix, you could try leaning your truck out at transisiton from boost to vacuum and low boost level to help spool up.

i wasnt hitting 60mph until half track, the second half it went from 60mph to mid 80'smph. i wasnt hitting full boost till half track.

out of my 16 or so runs, i only got one boost launch once. the rest i left at 2600 and no boost. i'll try leaning it out around the 100kpa/2600rpm area.

 

[91blazins10]

Re: 1/8th mile shakedown

what kind of boost controller you running?

 

[dgoodhue]

Re: 1/8th mile shakedown

i'll try leaning it out around the 100kpa/2600rpm area.

I would datalog a boost launch, to figure out what cell your hitting. I would also try leaning out as it starts build boost as well (a little bit at a time)

 

[Aeroking]

Re: 1/8th mile shakedown

funny thing is with the Code59 autotune, it always puts my 101kpa (0 vac, 0 psi). really lean, which i richen up to make a smooth graph. i always wondered why it pulled the graph lean, just at 101kpa. is the target AFR set to aid in spoolup?

 

[91blazins10]

Re: 1/8th mile shakedown

http://www.code59.org/forum/topic.asp?TOPIC_ID=726


Try this.

 

[Aeroking]

Re: 1/8th mile shakedown

read the post, and i can understand how it might help spoolup, but cant really see it affecting it. Just for sheetz&giggles, i bumped mine up 60mSec's in the Delta contribution.

the way i understnad it, the AE only kicks in during a sudden change in VE. So when trying to spool on the line, the RPMs are steady, the TPS is steady, and the kpa is steady, so i cant see AE really helping spoolup. but maybe i dont understand it right.

now by bumping up the mSec's of the AE delta contrib. wouldnt that mean that i am slowing the AE response time by (50-100) mSec's? and making the AE less effective.

 

[sy#2921]

Re: 1/8th mile shakedown

funny thing is with the Code59 autotune, it always puts my 101kpa (0 vac, 0 psi). really lean, which i richen up to make a smooth graph. i always wondered why it pulled the graph lean, just at 101kpa. is the target AFR set to aid in spoolup?

What kind of numbers are in your F29_AFR table in those lean areas?

 

[Aeroking]

Re: 1/8th mile shakedown

my F29_AFR is the one that was in Autotune 1.5.

101kpa, and 2800rpms is 15.20 on F29_AFR

 

[sy#2921]

Re: 1/8th mile shakedown

You can play around with that table to make your afr's what you want for your truck. Lower the numbers in that table and you will see what autotune wont make it lean there anymore since that is not what you want. Autotune is just comparing your F29_AFR to your wideband input and telling you the approx ve change to get to the afr table number

 

[Aeroking]

Re: 1/8th mile shakedown

ok, i'll play with the F29_AFR, cause my fuel trim has lean dips at the 71kpa and 101kpa points. i'll pull the 29-AFR down, so the 29x goes up, and makes a smooth graph. see if that helps at all.