Pontiac Grand Prix Forums : Grandprix

fst · #1 02-18-2008, 09:05 PM

i have a PT, but after so many adjustments to get rid of the massive KR i'd get from when i apply the throttle from a rolling speed, ie-65mph, im stumped. when i say massive, i mean as much as 15*

. my thought would be the TCC not unlocking soon enough when i gradually apply throttle and theres alot of load on the TCC right b4 it reaches the specified TPS to downshift.

one attempt, i tried raising both my 4th unlock and lock above 30%-50% by 3-4mph but still no cure. i then lowered my PE enable at 39mph from 0-50% TPS. i even tried to lower the 4-3 downshift by 3-4mph, thinking the lower mph downshift would be alright with the TCC locking higher than that.

any ideas on how i can either rid of the massive load of the TCC and having it unlock quicker or at least something close to that?

my only alternative at the moment is is whenever i apply throttle at a highway roll i tap the breaks and the TCC unlocks immediately and the RPMs quickly rises from the staggering 2000RPMs to ~3200RPMs and i can wisk away from 65mph to 75mph to pass slower traffic.
TIA for your suggestions and advices!!

Trannyman95 · #2 02-18-2008, 09:47 PM

I use HPT so I dont know what you have to work with but if you are seeing 15 deg of KR on a downshift then TCC shouldnt be your concern area. Do you have wideband access or at least can you watch your 02s when the KR goes up? It sounds like you arent getting enough fuel in the right area or it is just false KR. 15 is an extremely high number and if it was real kr then I would think you would hear audable pinging. You should be able to make TCC unlock at a very low throttle position in the tune but you need to make sure it isnt going to kick out going up a hill with cruise on. You may need to look at your PE tables and add some fuel during tip-in areas and see if that helps. What are your torque management settings for downshifts? Try turning all of your TCC in 4th speeds up to 255 and go down the road and then try rolling into the throttle for a downshift and see if it still has the same KR. Letting ouf of the throttle to unlock TCC then getting back into is different than it not being applied at all and keeping steady throttle.

fst · #3 02-19-2008, 05:08 AM

tanks tranyman. im running the 42.5# injectors and i increased my AE enrichment somewhat alot at the areas between 30-45%. the huge amount of KR tapers off though if i hold steady throttle and get the downshift, but if i let off and got on it in a couple seconds the KR disappears. i do want to have the TCC unlock at a lower TPS, but from what i read on the DHP forums, from my understand actually, is to raise the TCC apply along with the release. am i reading it wrong? should i raise only the 4th gear apply and lower the 4th gear release below either or both my PE enable and 4-3 downshift speed?

fst · #4 02-19-2008, 05:27 AM

torque management settings, i'll have to go back and look, otherwise if u had a PT, i'd send u my bin to look at but you have HPT instead.

Zef_66 · #5 02-19-2008, 06:48 AM

I was getting the same thing you are getting. I raised my AE a lot and this took care of it.

I can't wait till I get my WB from DuBob so I can tune better in situations like these.

fst · #6 02-19-2008, 07:11 AM

derek, maybe your symptoms are the same as mine, but just to be certain, the KR i get can be related to when you drive with cruise control on and going uphill. the angle of going uphill doesnt trigger the pcm to downshift, but the car builds boost and increases alot of load on the car, and it'll cause huge KR to build as much as 15*. once more throttle is increased and downshifts it'll be alright or apply the brakes and the tcc unlocks and the RPMs rise to 3K.

however i'll raise my AE enrichment tables from the 25-35% by another 5% and see how it goes.

IndeedSS · #7 02-19-2008, 07:50 AM

fwiw. HPTuners can read the DHP bin and if that year is licensed in the HPT, it can be edited. Although if editing is done by a reputable vendor (Trannyman etc.) then said vendor should be payed for his help IMO. Time is money when your business is tuning, engine and tranny building. Quick advise is another thing... don't hate the messenger, just looking out for all of our current and upcoming business owners.

fst · #8 02-19-2008, 08:03 AM

thanks indeedss, im not hating. if anything, im hating myself for not getting this tune for the trans setup correctly.

Zef_66 · #9 02-19-2008, 08:12 AM

Originally Posted by fst

derek, maybe your symptoms are the same as mine, but just to be certain, the KR i get can be related to when you drive with cruise control on and going uphill. the angle of going uphill doesnt trigger the pcm to downshift, but the car builds boost and increases alot of load on the car, and it'll cause huge KR to build as much as 15*. once more throttle is increased and downshifts it'll be alright or apply the brakes and the tcc unlocks and the RPMs rise to 3K.

however i'll raise my AE enrichment tables from the 25-35% by another 5% and see how it goes.

Yes, this is similar to the problem I had if I remember correctly.

But, another issue that I see, is that the PCM has different tables that it uses when cruise control is on. This includes TCC lock/unlock, shift points, etc. So when using cruise, my car will drive different, and get knock going up hills because of these different tables. So if I see a big hill coming, I knock the cruise off, and control it myself so I don't get knock. Just one of those things where more tables would help us tune our cars better. But, I don't see us getting access to those things.

But kinda offtopic, I would like to have my TC engage a little firmer. Is that possible with HPT?

IndeedSS · #10 02-19-2008, 08:16 AM

Originally Posted by fst

thanks indeedss, im not hating. if anything, im hating myself for not getting this tune for the trans setup correctly.

Eventhough this was your thread, my point was generalized. It certainly was not directed at you, if you felt that way I apologize. More a food for thought, as some of our vendors may be to polite to say anything. Some of these guys make their living doing this stuff.

it would be nice if .bin and .hpt files could be uploaded here like JPG's. Of cousre that would only be appropriate if it was NOT a vendors tune. NO DHP 1.0, 1.5, ZZP, Intense, Overkill HMS...etc.

DuBob · #11 02-19-2008, 09:47 AM

Freeman, how much timing are you commanding when you get all this KR? What % throttle does the TPS show, what is your MAP reading, and what is your wideband showing. I'm just wondering if you aren't going into PE mode when you get all this KR.

I'm also wondering if the VS cam will help with this......since it'll help move more air in and out of the motor.

fst · #12 02-19-2008, 09:56 AM

I apologize for not having a logged scan since its something I should start doing(only log at PE/WOT). From my visual and memory, this happens around(guesstimating) 28-38% and the RPMs would be ~1700-2200RPMs pending if there’s a slight incline. Im already building boost at this point, approximately 1-2#. My timing is set at 21*.

I tried to adjust the Timing Air Temp table to start adding timing starting at like the last 3 rows for the Mg/Cyl. Maybe I can lower the timing commanded under the Good Spark Table starting at like 300Mg/Cyl? I don’t know my MAP since I don’t use that parameter. WB shows somewhere in between 11.4-11.7 and in the PT I have the AE commanded AFR at 12.2. Also I should note my alky doesn’t turn on until ~3-3.25#. again my PE I have set currently is at 39mph, but it was still doing this issue at the stock 40mph.

DuBob · #13 02-19-2008, 10:06 AM

TCC locked with 1700-2200 RPM's is putting a lot of stress on the motor at that time, thus timing commanded is usually very low. I'd get a good scan to show it happening, log the A/F from the WB too.

If you are passing from 99 to 101 on the MAP below where your PE is set to enable, that could be causing a lean condition as you are building boost. Like I said above though, once you get that VS cam in there, you'll be moving more air in and out that this issue could go away.

What pulley are you running right now anyway?

fst · #14 02-19-2008, 10:45 AM

i'll try to remember to get a log whenever im on the highway as well as log MAP(gotta double-check if the LS1M logs that parameter or not. i dont have my WB hooked up yet as i still dont know how to wire it up to the PT correctly >.<
im running the 3.2 pulley right now.

fst · #15 02-19-2008, 10:51 AM

dave, do u think its a motor issue and not a tranny issue?

Trannyman95 · #16 02-19-2008, 04:07 PM

If you are under boost and the car isnt richening up then you need to work on the engine tune some more, but withough a wideband it is going to be hard to do without some trial and error.

fst · #17 02-20-2008, 06:44 AM

well, i went ahead and increased my AE enrichment from 20-100%. i compared my current table and one of my earlier tables back b4 adding the 42.5# injectors. the current table was leaned out somewhat, and i think i did that cause of the 42.5# injectors. for example my 20% was like 107 compared to my older table at 112 and the 30% was at like 122 compared to the older table of 129, etc etc.

Zef_66 · #18 02-20-2008, 06:46 AM

Originally Posted by fst

well, i went ahead and increased my AE enrichment from 20-100%. i compared my current table and one of my earlier tables back b4 adding the 42.5# injectors. the current table was leaned out somewhat, and i think i did that cause of the 42.5# injectors. for example my 20% was like 107 compared to my older table at 112 and the 30% was at like 122 compared to the older table of 129, etc etc.

Did it help?

I can't see a reason to ever lean out the AE from stock. If anything, you need more fuel.

fst · #19 02-20-2008, 08:21 AM

i just did a rewrite b4 i headed into work this morning, so i have to wait til after work as well as drive a few miles until the trans relearns itself-shift pressure, etc. i'll keep ya'll posted. thanks for the suggestions though everyone!

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Tuning for the turbo	TurboKent	Turbo	11	05-27-2008 10:33 PM
Any Read me's for Tuning?	mainecrab	PCM Tuning	2	02-11-2008 09:39 PM

Login		Remember me?
Password

Pontiac Grand Prix Forums : Grandprix

Help on Tuning: quicker TCC unlock=less massive KR for downshift