NightOwl

Does the predator make changes to timing/fuel at less than WOT that would be a benefit at normal cruise?

CAT3

iTrader: (9)

Dont think so. I just did a wideband dyno yesterday. after the first two pulls netting a 11.3:1 afr, with the PE table @ +5%, I reset the paramaters and took out fuel, putitng it back to base line. ran two more runs and had 11.9 and 12.1:1 afr, when it should have been 12.8 with that much change. Next two runs, took out all the fuel and got a 12.3 or 8 cant remember that one. Throughout allt he runs, the idle, and PT afr never changed, they stayed at 14.7 idle and cruise, but then PT went to 13.4. The timing also never changed at idle/PT between runs with + timing and then - timing. First couple runs I had 34.4* of timing, and then I centered the timing and got 30.4*, also odd becuase the predator is only supposed to give or take 2* at WOT, not 4*.
So, from what I have seen there is no change in the PE/Timing tables except when WOT, but then its not as claimed only being 2* of timing, and then the PE is supposed to be 1.5 on a wideband afr, when changed 5%.

Jpr5690

iTrader: (13)

witht he predator i belive the prefab tunning program is for wot only but you can adjust spark and fuel for other than wot i belive now for a stock car it would not benfit cruseing i belive but there is power to be gained at wot check out the new edtion of gm high tech they did an article on it this month

jimmyblue

iTrader: (11)

The power enrichment does affect part throttle.
Its effect is less there than at WOT but it does
act to suppress pinging at higher spark advances,
you can see this for yourself if you monitor KR
while driving around. A 0% PE, +10% spark makes
my motor ping at stoplight part-throttle takeoffs,
+2% PE makes all knock and KR go away.

Maybe someone who really knows can explain the PE
action, where & how much. All I know is what I've
seen & done.

Normal cruise is closed loop and PE does not make
the PCM give up trying. I believe where the PE
part-throttle benefits play, is during throttle
transients where the loop is unable to track, and
you fall back on straight mixture calculation.
Here it is better to have some "rich margin" or
you will ping. You can get high MAP and cylinder
pressures with only partial throttle, at low RPM.
This does not qualify as "WOT" but it has the same
knock-precipitating characteristics. At 2000RPM
you only need 1/3 throttle to match 6000RPM WOT
cylinder filling.

CAT3: 11.3 / 0.95 = 11.9; you got just what should
be expected by removing 5% PE.

CAT3

iTrader: (9)

Jimmybule, Not really. According to the literature and talking with the vendor, by adding or removing 5%, the afr should move 1.5, e.g. if center is 13:1 then add 5% should be 11.5:1. I had mine at +5%, move it to center and only leaned it out .6 on the wideband. That was the problem. I care less how much it actually makes, but if you tell me it moves "X" then I expect that. BTW, my car and "custom" predator tune has a different ratio on the wideband than my friends, his customtune and moving the PE 5% is more like a difference of 2.0 on afr.

jpr5690- No, you can only adjust for WOT, yes it may play a part as explained by jimmyblue, but the spark and fuel even with custom tune is WOT operation only. And yes, I have tried various different settings and cobos with my predator and seen the only difference is WOT. Still better then the HPP.

DiabloSport Products Informant

Hello sir, and thanks for your input on this matter, but that information above is not correct. The Predator's canned tuning, and our custom tuning, does affect the ENTIRE rpm band at ALL throttle positions. We do not tune just for WOT mode as some manufacturers do. If you get a custom tune from us, we can make any and all changes to the pcm that GM can do, or even other tuning software, like Edit. This is fact, so please do not let anyone else tell you differently.

Now, with that said, the end-user options on the Predator are able to affect PE mode ONLY, however, as jimmy stated, they will affect some closed loop. Please remember what I just stated previously, though, and that is our custom tuning can make any changes to any throttle position, closed/open loop, at any rpm, etc. We have been doing custom tuning for quite some time, with excellent results, for all forms of possible combinations.

Regards!

CAT3

iTrader: (9)

Thanks bud, but that was my point, as the end user you (I, or he being jpr5690) can only adjust WOT. You, then vendor tuner can do all the other parameters and the likes.

Since you stated you can do any and all adjustments like Edit, can you do a fill value in the low and med rpm by cyl tables and other tables to keep the false misfire code setting from cam install? My vendor says not at this time, which means one of you is not that accurate. Either you can, and my vendor doesnt know how yet, which he seems to understand exactly what I am asking for since I emailed him the discussion off from here, or you really cant do any and all tuning like Edit...At this time?
Personally I have had good luck with the tuning up to this point and my vendor is extremely helpful. So please dont think I am knocking yoru product, I have been here tryign to gelp others with the Predator to get the right info to their vendors and such.

Thank you Sir.

Charlie.

Drew778

iTrader: (2)

TTT

DiabloSport Products Informant

Charlie, your vendor (RWTD) will be able to do that most likely this coming week or the next week (so please shoot him over an email when you can). We know where all the parameters are in the pcm for being able to do this (and many other things), but we're having to map it all out for the software.

Thank you for your support!

ss rally red

iTrader: (8)

I sure don't want to highjack this thread but I want to ask a question. If I haven't had a chance to do a wideband dyno but with the Predator tune plus 10% timing added and 2% PE I have no KR. Should I try to scale PE down until I get some KR and adjust up a little or should I leave the cushion I have now? Thanks.

CAT3

iTrader: (9)

You can. I scaled it down right off the bat, after looking at my plugs (before the crapped out), and then added timing. Was at +10spark, and -5% PE, although I didnt get any KR, the fact is, IF you get knock with an assload of timing you dont need, you are more susceptible to catastophic failure. I really did not see any difference dyno with 34.4* to 30.4*. So, I left it the lower of the two.

Good Luck.