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Discussion Starter · #1 ·
Riding along at pretty much any speed, if I nail the throttle enough to get into pretty much any boost (1 - 13psi) I get bad knock, the more boost the more knock. If I ride it out (say 4-6 seconds) the knock drops to 0, and I can 'feel' the car get faster.

Do I need to adjust my AE or PE to 'splash' some gas in there to help reduce / remove that knock?


BTW, it does it w/ pretty much any kind of fuel, and any size pulley.

Jason
 

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Discussion Starter · #2 ·
It was just brought to my attention that there is a 'tip in' adjustment in the pcm as well. Perhaps this needs to be adjusted?
 

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Well AE is the splash of fuel that is given at the set TP percentage.

I wouldTHINK that bumping the AE to an earlier percent as well as a higher amount would help.. PE ould be richened too but IMO it would be an AE problem.

FWIW I have the same damn problem. :(
 

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Discussion Starter · #4 ·
Scott? CG?

Come on, Y'all have to know.


Share the info, I want to have this thing dialed in for MGM :-D


Jason
 

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Discussion Starter · #5 ·
Is this some sort of huge secret?

This is a fourm to get information on the 3.8l buick motor right?

I know someone has to know this.


Where are you at Mr. Intense?
 

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Okay dumb noob question here.

What is AE and PE? Im trying to figure out this whole tuning thing also. Im searching my ass of for ways to learn, and not having much luck.

Sorry for hi-jacking your post,

Scott
 

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ZR2_S10 said:
Riding along at pretty much any speed, if I nail the throttle enough to get into pretty much any boost (1 - 13psi) I get bad knock, the more boost the more knock. If I ride it out (say 4-6 seconds) the knock drops to 0, and I can 'feel' the car get faster.

Do I need to adjust my AE or PE to 'splash' some gas in there to help reduce / remove that knock?


BTW, it does it w/ pretty much any kind of fuel, and any size pulley.

Jason

Could it maybe be false KR?
 

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AE (Acceleration Enrichment)- the splash of fuel that is added when yout TPS(throttle pos. sensor) goes past a certain percent. Say 60% for example.... this gives you a little extra splash of fuel on your way to WOT and helps combat KR.

PE (Power Enrichment)- the "new" fueling your cars PCM is shooting for under WOT. Under normal driving conditions, the target a/f ratio is somthing like 14.7. When you go WOT you want it to be more rich. I believe the stock PE a/f is somthing like 12.7 There are also alterations to PE in relation to rpms and time in PE.
 

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Discussion Starter · #9 ·
firemangtp said:
AE (Acceleration Enrichment)- the splash of fuel that is added when yout TPS(throttle pos. sensor) goes past a certain percent. Say 60% for example.... this gives you a little extra splash of fuel on your way to WOT and helps combat KR.

PE (Power Enrichment)- the "new" fueling your cars PCM is shooting for under WOT. Under normal driving conditions, the target a/f ratio is somthing like 14.7. When you go WOT you want it to be more rich. I believe the stock PE a/f is somthing like 12.7 There are also alterations to PE in relation to rpms and time in PE.
Ok, is there a 'starting point' to work from? Some ballpark numbers?


Does Mr. Intense reply to threads like this or just the introduction threads? I thought that since his PCM's are doing so well, that perhaps he would have a little insite on this. I attempted to PM him, but it seems he has PM function disabled on his account.
 

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I am looking at HPTuners right now and I don't see an AE table. There are two PE tables, one is PE vs RPM and one is PE vs TPS. The PE vs TPS table is all zeroed too.

Maybe the 04's are different, but I just don't see it here unless I am looking under the wrong tab.
 

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ZR2_S10 said:
Does Mr. Intense reply to threads like this or just the introduction threads? I thought that since his PCM's are doing so well, that perhaps he would have a little insite on this. I attempted to PM him, but it seems he has PM function disabled on his account.
Don't take it out on individuals.

IMHO Most everyone in the 3800 with HP Tuner crowd are new at personal tuning. Most if not all are somewhat reluctant at sharing info on their tuning methods due to a few reasons.
1. few feel comfortable enough with their tuning experiance to share info.
2. no one wants to tell you, "this worked for me", you put the values into your table and then you have serious problems and blame them. Every car is different.

I don't think purchased PCM's are nearly as involved as the HP Tuner allows. The values you may be asking advise on may be values that depend greatly on your particular mod list. There are no magic values that work for everyone.

You may find better info, at this time, by visiting the HP Tuner forum or LS1 forums and reading as much as you can. These groups have had more experience with personal tuning. It's frustrating having the tool and not knowing how to use it. Good Luck
 

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Sorry, I should have responded earlier, but I thought you asking about AE you were specifically asking about the DHP tuner, as AE is not part of the HP Tuners suite. Perhaps it goes by a different name there. I'm only familiar with the HP Tuners package.

You may want to check out the Fuel System forum where I had some discussion about all this.

Anyway, there are 3 PE tables. The Base vs ECT, the additional vs TPS, and the additional vs RPM vs time. All 3 tables are used together to calculate the fueling (AFR) that your PCM will aim for once the car gets into PE mode. (BTW, it gets into PE mode fairly early on the throttle.) The appropriate entries from each table are added together to get to the desired AFR. For this reason alone, AFR should always be scanned when you log as it tell you (1) when the car gets into PE, and (2) how much fuel it's really trying to add. These two pieces of info will also tell you how far into the add vs RPM vs time table you are in, and this is the most dynamic part of fueling and can also be the hardest to understand. Please check some of my posts in Fueling System.

As to what these table do, the Base table is pretty much just that. It sets the base for the AFR when you first enter AFR. Any change in this table will be reflected across the board for all RPMs, TPS, and time. Based on your description, this is probably not the table you want.

The add vs TPS is used to lean out the AFR for very low TPS settings. It should not be all zeroes, rather it has some positive non-zero values for low TPS (to lean the car out) and goes to zero for higher TPS values. This is the table that will help you. What you want to do is to slide the entries to the left a little. That will result in adding more fuel earlier on the TPS scale. Go slow and see how much that helps.

The add vs RPM vs time table is used to add more fuel as the RPMs climb, and also more and more fuel based on just how long you've been in PE mode. This is done to keep the engine cooler and in one piece for somebody doing prolonged WOT runs. I explained this table in detail at:
http://www.3800tech.com/forum/showthread.php?t=293

John
 

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johnt said:
The add vs TPS is used to lean out the AFR for very low TPS settings. It should not be all zeroes, rather it has some positive non-zero values for low TPS (to lean the car out) and goes to zero for higher TPS values.
Mine is all zero's from the facory, FYI, unless HPTuners is reading it wrong - and there are a few bugs in the software still so I wouldn't count it out.

Also, the LS1's have a burst knock table which pulls timing as a function of the change in the airflow. I am very surprised that the GP's don't have this table in there, since the delta's are much bigger with boost.

The alternative method is generally ASSUMED to be that on large changes in the airflow, the PCM figures in the VE tables to adjust the fueling. Like I said, this is the assumed method of fueling, and only the guys at GM know for sure, and they are not talking. So I always bump my VE tables percentagewise relative to the horespower gains I have made just to keep them a bit close.

-Geoff
 

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Add vs TPS Stock '98 GTP
0 - 100 (0, 5, 10 15, 20, 25........)
2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.02 0.72 0.45 0.26 0.1 0.01 0 0 0 0 0 0 0
 
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