HELP!! my truck is slow
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single digit dreamer
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Joined: Mar 2002
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From: omaha ne
HELP!! my truck is slow i have a most of my parts installed, it is time to tune this thing and i have no idea where to start or what to do, i need some serious help.
i have a 99 4wd ext cab 1/2 ton with a whipple, 2002 6.0, yank 3000, 41lb injectors, ls1edit, atap. i have some headers ordered but right now i have the stock 5.3 exhaust. right now i am running a 5psi pully but have a 3, 6 and 8.
so far i have raised the rev limiter to 6k, shift points to 5600, adjusted the injector flow rate for the 41's. the truck is only about 4/10th's faster than with just the whipple(when on the stock 5.3) i should be close to a sec faster i would think. where do i start? i have heard of ltrims, or what about my wot mix, i have some atap runs, i dont know if i need more fuel? less timing? more boost? better gas? where should i start?
last year 5.3 with whipple(6.5psi) 15.32@92.3
this year all above at 5psi 14.95@90.7
i have a 99 4wd ext cab 1/2 ton with a whipple, 2002 6.0, yank 3000, 41lb injectors, ls1edit, atap. i have some headers ordered but right now i have the stock 5.3 exhaust. right now i am running a 5psi pully but have a 3, 6 and 8.
so far i have raised the rev limiter to 6k, shift points to 5600, adjusted the injector flow rate for the 41's. the truck is only about 4/10th's faster than with just the whipple(when on the stock 5.3) i should be close to a sec faster i would think. where do i start? i have heard of ltrims, or what about my wot mix, i have some atap runs, i dont know if i need more fuel? less timing? more boost? better gas? where should i start?
last year 5.3 with whipple(6.5psi) 15.32@92.3
this year all above at 5psi 14.95@90.7
Thread Starter
single digit dreamer
iTrader: (6)
Joined: Mar 2002
Posts: 9,757
Likes: 4
From: omaha ne
Re: HELP!! my truck is slow ok, i have been doing some reading and here are my plans for the day, corect me if i am going about this wrong.
put on the 6psi pully since this is where i plan on running most of the time
get some atap logs(MAF gm/sec, MAF input frequency, Ltrims)
adjust the MAF tabe in edit
repeat until Ltrims are around -5
make some more atap logs at WOT looking at(o2's?, ltrims?)
adjust for WOT mix in the PEvsRPM file
not going to worry about timing unless the KR maxes out at 8deg, adjust timing when finished with above.
is this the right procedure to start my tuning? ios 15min or so enuff time so see changes that i made or does the computer need more time.
put on the 6psi pully since this is where i plan on running most of the time
get some atap logs(MAF gm/sec, MAF input frequency, Ltrims)
adjust the MAF tabe in edit
repeat until Ltrims are around -5
make some more atap logs at WOT looking at(o2's?, ltrims?)
adjust for WOT mix in the PEvsRPM file
not going to worry about timing unless the KR maxes out at 8deg, adjust timing when finished with above.
is this the right procedure to start my tuning? ios 15min or so enuff time so see changes that i made or does the computer need more time.
Thread Starter
single digit dreamer
iTrader: (6)
Joined: Mar 2002
Posts: 9,757
Likes: 4
From: omaha ne
Re: HELP!! my truck is slow i have some atap numbers, this is about a 15min log driving around town, maybe 30sec of it was over 50%throttle.
average ltrims were -2.55 and -3.34
high and low ltrims were +2 to -9
should i mess with this? it seems prety good to me. i am suprized that it isn't way off(6.0, whipple, 41lb injectors) i shouldn't bitch, the thing runs and drives great, it just isn't fast enuff when i open it up so i guess that is next. i am not sure what to log for the WOT tests, do i still use ltrims? or the o2's? or something else?
2hours later... i did some gtech/atap runs, this thing is just geting slower all the time, feels good at part throttle. there was some KR, it hits at the gear changes, is this real knock? the o2's were geting down to .85-.86 at the end of the run so i adjusted the PE vs rpm chart, now the o2's botom out at about .88 but the truck is slower still. i am hoping i have a major exhaust issue(stock 5.3 with cats and single 2 1/2 tail pipe)
i can pull some timing but i was hoping geting the o2's up a little would get rid of the knock.
average ltrims were -2.55 and -3.34
high and low ltrims were +2 to -9
should i mess with this? it seems prety good to me. i am suprized that it isn't way off(6.0, whipple, 41lb injectors) i shouldn't bitch, the thing runs and drives great, it just isn't fast enuff when i open it up so i guess that is next. i am not sure what to log for the WOT tests, do i still use ltrims? or the o2's? or something else?
2hours later... i did some gtech/atap runs, this thing is just geting slower all the time, feels good at part throttle. there was some KR, it hits at the gear changes, is this real knock? the o2's were geting down to .85-.86 at the end of the run so i adjusted the PE vs rpm chart, now the o2's botom out at about .88 but the truck is slower still. i am hoping i have a major exhaust issue(stock 5.3 with cats and single 2 1/2 tail pipe)
i can pull some timing but i was hoping geting the o2's up a little would get rid of the knock.
Re: HELP!! my truck is slow Unhook the rear exhaust section after the Y-pipe. (just unbolt the flange and seperate the pipes, don't completely remove the rear section) It will be loud, but should be fine to test a little. See if you have any gains with a less restrictive exhaust.
Re: HELP!! my truck is slow Parish
If you'd like I can send you a copy of the .ls1 file I used from my friends Vortech car. It will give you a good starting point. Timing is conservative and there is a lot of fuel on top already. You will have to rescale for you injectors though.
Whipple type chargers generate lots of heat. That is what will kill your power. There is no way to cool the charge because of the design. You could perhaps consider water injection to help out with detonation and higher boost.
Start with low timing and lots of fuel. My experience is that fuel=power with forced induction.
If you'd like I can send you a copy of the .ls1 file I used from my friends Vortech car. It will give you a good starting point. Timing is conservative and there is a lot of fuel on top already. You will have to rescale for you injectors though.
Whipple type chargers generate lots of heat. That is what will kill your power. There is no way to cool the charge because of the design. You could perhaps consider water injection to help out with detonation and higher boost.
Start with low timing and lots of fuel. My experience is that fuel=power with forced induction.
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Thread Starter
single digit dreamer
iTrader: (6)
Joined: Mar 2002
Posts: 9,757
Likes: 4
From: omaha ne
Re: HELP!! my truck is slow ahhh, thanks for the replys, i have been waiting anxiously to see what you guys thought, i will push the o2's up to .95 and see what happens, i bet my injectors will be working prety hard, right now they are at 80% duty cycle. i figured since it was only asking for 9deg it would be ok, what should i set it back to? 5deg? even less? any idea why the o2's would fall based on speed? they are better in first at 5500rpm(.91 or so) and worse in 2nd at 5500rpm(.88-.89)
thanks for sending my that file but ls1edit wont let me open it, says that it is unliseced, i think it will only let me open a truck file.
i will probably be trying water injection or maybe mixing a little of my own gas(xylene) but i would like to get it running a little better right now.
thanks for sending my that file but ls1edit wont let me open it, says that it is unliseced, i think it will only let me open a truck file.
i will probably be trying water injection or maybe mixing a little of my own gas(xylene) but i would like to get it running a little better right now.
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