Results 1 to 10 of 10
-
05-02-2007, 02:44 AM #1
Trans tuning Questions for the trans guru
I am unable to get a snappy 1-2 shift at full throttle with the HPtuner trans tuning. I have the trans very snappy for everything under full throttle and I'm pretty happy.
Right now delivered trans torque at the 1-2 full throttle shift is 278 ft lbs. On my base shift pressure I already have 85 from 260 ft lbs. on up and it hits the max of 96 at around 300 ft lbs.
As you can see I am already near the max of 96 the graph indicates. Not sure where else to go from here.
I have looked at the pressure multiplier table and it's currently got #1 in the areas the trans operates, which to me doesn't seem like much of anything. Anyone mess with this table? Since I am close to max pressure accoring to the base table,,,will the multiplier table override that? Or will it just hit a dead end? I need it to shift harder on the 1-2,,,,the 2-3 and 3-4 are okay. I am getting some good ideas on Hptuner but I need to post the tune to get any further, and I am working on trying to accomplish that Thanks, Larry.
-
05-02-2007, 04:25 AM #2
you might be having a problem with the 2nd gear band getting worn.
to post the tune on hptuners, use the attachment feature, when making a post.Cold Air Intake, Muffler Delete, Vinci High Performance Dual Valve Springs, Hardened Pushrods, Yella Terra 1.85 Rockers, Some Hydropdipped Stuff, Strut Tower Brace, Some SS Badges, boost/vacuum gauge, fuel pressure gauge, some checkered stripes, drilled/slotted rotors, ZL1addons Stealth wickerbill, Ruxifey LED side markers
-
05-02-2007, 04:39 AM #3
- Join Date
- Apr 2007
- Location
- San Diego
- Posts
- 177
Red- 2002 T/A
do you have a shift kit?
-
05-02-2007, 07:21 AM #4
No shift kit. I am pretty sure the trans is healthy. I can turn up the line pressure manually at the EPC solenoid and it bangs second gear hard. But when I turn that back to stock and try to do it with line pressure in HPtuner I can't get WOT 1-2 shift very snappy. I seem to be missing an adjustment somewhere? There has to be a reason why I can do it manually but can't do it with the computer,,,,,,I know I am a computer dummy, you don't have to point that out
-
05-02-2007, 01:08 PM #5
- Join Date
- Apr 2007
- Location
- San Diego
- Posts
- 177
Red- 2002 T/A
I was having too much 1-2 SNAP after shift kit+upping pressures.
Do you have traction control?
-
05-02-2007, 03:10 PM #6
Ya I have traction control,,,but I always turn that off with the switch on the dash. Does it still have some effect even when turned off?
-
05-02-2007, 07:02 PM #7
- Join Date
- Apr 2007
- Location
- San Diego
- Posts
- 177
Red- 2002 T/A
-
05-02-2007, 07:09 PM #8
- Join Date
- Jan 2006
- Location
- Shepherd, Michigan
- Age
- 36
- Posts
- 11,770
blacker than wesleysnipes- 98' trans am
get the shift kit. it will take care of that 1-2 wot shift..trust me
-
05-07-2007, 12:04 AM #9
- Join Date
- Oct 2005
- Location
- calif.
- Posts
- 214
The other tables that determine shift "snappiness" is the "shift time " table.Stock is usually about .45 secs. at low tps and then slows up as you go to WOT to about .54. When tuning many tuners including myself lower this # to .20 on the entire 1-2 shift table. The other table that would effect a sharp shift would be the TQ management or the TQ Reduction Upshift table---as much as 30% of the TQ can be subtracted at WOT during the 1-2 shft -making it sluggish--at maximum TQ it takes out as much as 37% on some cars----STOCK-- !!!!--It is not safe to command any less than a .20 shift time but a .20 is completly safe--as far as TQ reduction or management that is a personal choice on how much protection you want to keep in for your drivetrain--A safe amount that I take out often is 1/2 or 50%--And then I've taken out all of it with no problems also --but you are gonig to have to make that call--As an example on my friends C5 with about 325 RWHP we took allof the TM out--been that way for 2 years and all is fine--On my C5 with 390 RWHP I only took out 15 % in 1st gear as the shift is very violent with any more taken out and it breaks the tires loose badly--howver in the 2-3 and 3-4 shifts I have 50% taken out and it works all fine-- My opinion of course--
-
05-07-2007, 02:54 AM #10
Interesting info on that tblu92,,,,thanks for sharing. I am starting to get a handle on it now. It's working better, just looking for a little more. I played with it at the track last weekend and made a little progress,,,,
Thread Information
Users Browsing this Thread
There are currently 1 users browsing this thread. (0 members and 1 guests)
Similar Threads
-
Tuning guru question.....
By Firebirdjones in forum Computer & TuningReplies: 10Last Post: 08-15-2011, 09:33 AM -
Help: Trans tuning 99 ta
By White99ta in forum Computer & TuningReplies: 0Last Post: 07-19-2011, 07:47 PM -
Trans tuning
By RAWPWR3 in forum Computer & TuningReplies: 11Last Post: 10-13-2008, 04:09 AM -
98 trans am tuning
By tjclt250r in forum Computer & TuningReplies: 7Last Post: 04-15-2008, 05:28 PM -
Need A tuning Guru!!!
By UltraZ28 in forum Computer & TuningReplies: 6Last Post: 04-25-2006, 10:52 AM
Bookmarks