1/8th mile shakedown

JSM

JSM

Active member
Re: 1/8th mile shakedown

Larger AE #'s will shoot extra fuel in during changes in throttle or MAP. The # you see is how many extra milliseconds of fuel is added during those changes.

I shoot for about 14.7 AFR all the way to 5psi of boost or so, then slowly blend to 11 (with meth), 12 (without) at about 16-17psi.

Little bit of extra timing during spoolup can help you also.
 
Aeroking

Aeroking

e.i.
Re: 1/8th mile shakedown

ok, i get it. so the mSec value is how long the injector sprays, ok. i'll also try leaning it out at higher boost to 12 AFR instead of 11, or as i was running 10.8.

I was just about to start changing the timing, and my idle suddenly dropped down to the set 875 (it was idling at 1600, for some mysterious reason). so i had to change the F28 EGR injector value to get 14.7 at idle. my EGR value went from 124 to 127. which messed with my 29x abit, but not too bad. i'm finishing the changes today. then try to change the AFRs, and then timing.

i go to the 1/4 mile in 2 weeks, so i'll try to get everything set by then.
 
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Aeroking

Aeroking

e.i.
Re: 1/8th mile shakedown

ok, i bumped my 29_AFR up 0.50afr from the current values at 2800rpm, and rounded the neighboring cells.

is 0.50 AFR going to make the spoolup difference i'm looking for? or will i need to go 1.0afr, or 2.0afr to the lean side, to help the spool. I took it out last night with the revised 29_AFR, and redid the 29x based off the datalog.

so tonight i'll be able to see if it helped spoolup or not.

thanks for all the info guys.
 
JSM

JSM

Active member
Re: 1/8th mile shakedown

Start slow, if .5AFR doesn't cause you knock, go another .5. Small steps, your doing it right.

You might do a log of just a spoolup against the brake. No need to launch if you dont' want to. Watch what cells it goes across via data tracing, compare the actual AFR. Might suprise you.

Also do some tuning just in neutral reving the engine up a bit, might be suprised how rich those cells can be.

On jeremy's syclone, all his 11 second runs were with the old code58 3 bar stuff. As a quick fix for a race version chip only, i cut his AE in half. Got it to spool a lot quicker at the track. Didn't run very well on street, but that wasn't the goal at the time.

He is now on code59 and although hasn't been to track lately, says it feels just as strong and runs much smoother now.
 
JSM

JSM

Active member
Re: 1/8th mile shakedown

Remember stall is determined by 2 things, how the convertor is made, AND how much torque you are making. We all know how to change a convertor out to another. But if you can also make more torque through tuning it can alter the stall a bit.
 
vanillagorilla

vanillagorilla

Member
Re: 1/8th mile shakedown

I've always found that too. If you advance the timing it'll stall higher (more torque) and allow it to build more boost. A 2 step wouldn't be a bad idea either.
 
Aeroking

Aeroking

e.i.
Re: 1/8th mile shakedown

i started playing with the timing, advancing till it knocks, then backing it down 2 degrees.

my stall 2800rpm/0psi timing advance was 15.4, now i set it to 31.2. it was knocking a little at 33.

i didnt get to launch it yet. but i have off work tomorrow, i'll tweak the timing more, and try launching.
 
sy#2921

sy#2921

BAMF
Re: 1/8th mile shakedown

email me a copy of your current bin. I might see something to help you out. Did you get mine?
 
Aeroking

Aeroking

e.i.
Re: 1/8th mile shakedown

hey Brandon.

notice the 29x valley at 101kpa. autotune actually tells me to drop those valves another 8-10 VE. i pull them up so the graph is a little smoother.

would i need to go into 29_AFR, and pull it way lean at 101kpa to give me a smooth 29x?
 
Aeroking

Aeroking

e.i.
Re: 1/8th mile shakedown

wait i got that backward.

with a lean valley in the 29x, i should pull the 29_AFR rich then. so that my VE valley comes up, and makes a smooth hill.
 
Aeroking

Aeroking

e.i.
Re: 1/8th mile shakedown

i noticed another problem. my actual AFR is not matching the Target AFR.

for instance, i spool thru the boost so fast, that my Target AFRs are 11.5, but my actual AFR is 13.5, and slowly falls to 11.5. but in the seconds that the AFRs are falling, the truckis running lean, and possibly knocking. I've suppressed the knock by retarding the timing.

how to i solve this, my actual AFR's cant keep up with the Target AFRs.

is this AE, or PE? or possibly 77x. bumping up the fuel multiplier?
 
sy#2921

sy#2921

BAMF
Re: 1/8th mile shakedown

Bump up the f21 table a 100 or so and see what happens. Also tune the truck for what it wants not just what autotune tells you. Manually look at the logs like you just did with the AE and see whats going on to get the tune closer. You should have such large changes from cell to cell in your bin. Also that hump seems a little weird to me in the boost onset low rpm range
 
Aeroking

Aeroking

e.i.
Re: 1/8th mile shakedown

13529afr.JPG


13629x.JPG


136f1.JPG
 
Aeroking

Aeroking

e.i.
Re: 1/8th mile shakedown

sy#2921 said:
Bump up the f21 table a 100 or so and see what happens. Also tune the truck for what it wants not just what autotune tells you. Manually look at the logs like you just did with the AE and see whats going on to get the tune closer. You should have such large changes from cell to cell in your bin. Also that hump seems a little weird to me in the boost onset low rpm range
Click to expand...

street tuning is tough to find "what the truck wants" lol.

i look at the logs, and look for irregular activity, and mismatched target/actual numbers.

the parts i'm not sure of is the target AFRs, i dont know if i'm close, or off or what. The timing is kinda easy. in-boost i advance till it knocks, then back it down a little. and in vacuum, i advance till it begins running rough, then back it down till its smooth again.

but my Target AFRs, i'm 14.7 from 00 to 71kpa. then drop to 11.5 at 169kpa. and i'm 0.10afr leaner from 2400rpm+ to help spool the turbo.
 
sy#2921

sy#2921

BAMF
Re: 1/8th mile shakedown

If your F29_AFR hasnt changed much or at all from what I saw I would not touch it anymore unless you have some knock issues when boost starts coming on. Its more than safe.

Email me a log or two so I could look at whats going on.

Also, what are you running for a wastegate? Just wondering for my truck
 
Aeroking

Aeroking

e.i.
Re: 1/8th mile shakedown

i bumped my AE up 100 ticks, i'll go out and make a log this morning.

as far as wastegate. i run a Tial 38mm. i bought it new off ebay. it came with a 9psi spring. i recently bought a 10psi spring. putting both in together the least i could control was 20psi, which was actually my target, but it was very tought to control 20. so i took out the 9psi spring, and left the 10psi spring. so now i have solid control. i use the boost valve from Detroit Turbo. simple little valve, but it works great.


100_1122.JPG




EDITED: ok, bumped the AEs up, but a little too far, so i backed them down. 480 at delta 40kpa, and 300 at delta 00kpa. i also pulled the valley outta my 29x graph, and both of these factors together helped me get my actual AFR to my desired AFR quicker. in my recent datalogs, i'm within 0.30 AFR at each data sample. got a few degrees knock at WOT, so i tweak the timing abit.

it spools quicker now. but not from 0psi to 5psi like i hoped. it's improved spooling from 5psi to 10psi. and 10 to 20 is still almost instantaneous.
 
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vanillagorilla

vanillagorilla

Member
Re: 1/8th mile shakedown

Are you spraying meth during all of this tuning? I might have missed where you said if you were or weren't.
 
Aeroking

Aeroking

e.i.
Re: 1/8th mile shakedown

no meth.


last night i took my 101kpa AFRs upto 14.2, from 13.6. and i was able to spool 3psi at 2800.

3psi to 8psi is still a little sluggish (60 foot). i'll pull those kpa's a little more lean, and see if it gets better. 10+psi, is still great.
 
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