[Z06] My Z is a demon after reprogramming
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Advanced
Joined: Oct 2003
Posts: 81
Likes: 2
From: gilbert az
My Z is a demon after reprogramming
Just finished programming with my Diablo. Richened it, and advanced spark at the low rpm, 2 degrees and at the high rpm - 6 degrees. It has awakened a demon beast from within. The only mods I have currently done are hallteck trap, license plate screen, and Nology plug wires. I can't believe the difference in performance. Revs extremely fast, it justs wants to get up and haul.......... Anyone have any ideas on the carbon fiber drive shaft. I was thinking of it and an aluminum flywheel as the next steps. I believe I want to mod in the direction of lightening the rotating mass and allowing the motor to rev faster. Not a huge amount of dollars and should be lots of sotp feel. Any thoughts from those who have a much greater understanding than myself is appreciate.
Race Director
Joined: Mar 2001
Posts: 14,480
Likes: 132
From: PA
Glad you're happy with it! But wait, if you're like most of us, in a few days you'll get back in the Z and wonder where all the extra power went. Then you'll go back and try adding more timing, leaning it out a bit more...then you'll be clueless like the rest of us with programmers that have no dyno to actually tune the car. I often wonder if we're just trying to convince our SOTPs that the $400 we just spent on the programmer actually did something. 
Melting Slicks
Joined: Mar 2001
Posts: 2,233
Likes: 5
I have talked to several tuners and they all agree the best tuning is done on a dyno. Of course they Do sell tuning. I talked to another Z owner who installed hedders and and an intake and had it dyno tuned. Big improvement in sound and power. For the money I would rather have a pro do it on a dyno. Just my 2 cents....... 
Pro
Joined: Jul 2003
Posts: 645
Likes: 1
From: Hillsdale NJ
Many simple do-it-yourself mods make the car sound louder and thus you may think it has produced more power.
Always baseline on a dyno first and then do mods and re-dyno each time a mod is added to objectively determine their impact, if any.
Keep in mind the Diablo adjustments are at WOT only.
Team Owner
Joined: Sep 1999
Posts: 20,054
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From: Swansea IL
Originally Posted by karelin
Richened it
Did someone advise you to "riched it"???
Tom
Melting Slicks
Joined: Sep 2003
Posts: 2,458
Likes: 105
From: Northville Michigan
Frank,
I would also like to caution you as AFVETTE and others have. I have had my Z06 and watched as a parage of 15 C5s were run across a chassis dyno on a Saturday afternoon. ALL of them were rich. Their exhausts poured out black smoke as soon as the dyno operator punch the throttle.
Usually, a Z06 can stand perhaps 2 degrees more top-end timing without getting into detonation if their air-fuel ratios is corrected to the 12.5 to 13.0:1 area where it should be.
I would also support the suggestion that you have your Z06 tuned on a chassis dyno, with a broadband air-fuel ratio bung inserted into the exhaust.
Good luck with your decision.
I would also like to caution you as AFVETTE and others have. I have had my Z06 and watched as a parage of 15 C5s were run across a chassis dyno on a Saturday afternoon. ALL of them were rich. Their exhausts poured out black smoke as soon as the dyno operator punch the throttle.
Usually, a Z06 can stand perhaps 2 degrees more top-end timing without getting into detonation if their air-fuel ratios is corrected to the 12.5 to 13.0:1 area where it should be.
I would also support the suggestion that you have your Z06 tuned on a chassis dyno, with a broadband air-fuel ratio bung inserted into the exhaust.
Good luck with your decision.
Le Mans Master
Joined: Jun 2001
Posts: 7,331
Likes: 518
From: Admit Nothing, Deny Everything, Make Counter Accusations.
Originally Posted by karelin
Just finished programming with my Diablo. Richened it, and advanced spark at the low rpm, 2 degrees and at the high rpm - 6 degrees.
The stock LS6 does very well with the stock 22 degrees total advance at high RPM/WOT.
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Team Owner
Joined: Oct 2001
Posts: 56,381
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The aluminum flywheel will be you best bang for buck, please compare weights and lbs before buying a CF torque tube!!!!!!! The next bang for buck in weight and road racing would be light racing seats. Long tubes/x-pipe will give you HP and weight savings; after that the only significant weight savings left is radical dismantling!!!!
Pro
Joined: Jan 2003
Posts: 503
Likes: 37
From: Warner Robins Georgia
I installed LG long tubes and a K&N and was running 3% lean on the LTFTs using EFILive to monitor. I programed with the Predator +3% and now my LTFTs are at 0 and slightly negative. I am very happy with the way the Predator has let me make adjustments. My exhaust tips are no longer sooty black and I can feel the added SOTP performance!
Le Mans Master
Joined: Jun 2001
Posts: 7,331
Likes: 518
From: Admit Nothing, Deny Everything, Make Counter Accusations.
Originally Posted by GotMoJo
I installed LG long tubes and a K&N and was running 3% lean on the LTFTs using EFILive to monitor. I programed with the Predator +3% and now my LTFTs are at 0 and slightly negative. I am very happy with the way the Predator has let me make adjustments. My exhaust tips are no longer sooty black and I can feel the added SOTP performance!
Dialing in +3% on the Predator is going to richen your WOT mixture up 3% across the board. It is not going to lower your closed loop LTFT values. Your car was probably running rich at WOT to begin with and you just made it run even richer. I doubt you gained power and you may have lost power. These cars cannot be reliably tuned by the seat of the pants (unless you are some sort of pro racer/tuner with a super sensitive butt). You really need the proper tools to tune these cars. I may be wrong but my opinion is that these handheld tuners are giving people a false sense of security. Everyone wants to believe that their car feels faster after spending $400 on something. In all reality if a 400 HP car gains or loses 5-10 HP it will be almost impossible to feel from the driver’s seat.
Le Mans Master
Joined: May 2003
Posts: 5,362
Likes: 3
From: Delray Beach FL
In defense of the Diablo Predator, there are a couple of bonuses:
1. Skip Shift is deactivated.
2. Predator Factory Tune is better than the GM Factory Tune.
3. It is also good for diagnostics.
I plan on eventually having my Z dyno-tuned and am going to see if they will tune it using my Predator, so I can load the new variables anytime I need to reprogram the computer. I am lucky that DiabloSport is located nearby, so they will be the first ones I contact about doing a custom tune on my Z.
1. Skip Shift is deactivated.
2. Predator Factory Tune is better than the GM Factory Tune.
3. It is also good for diagnostics.
I plan on eventually having my Z dyno-tuned and am going to see if they will tune it using my Predator, so I can load the new variables anytime I need to reprogram the computer. I am lucky that DiabloSport is located nearby, so they will be the first ones I contact about doing a custom tune on my Z.
Thread Starter
Advanced
Joined: Oct 2003
Posts: 81
Likes: 2
From: gilbert az
Dyno Run questions
I had installed a custom 3" exhaust system all the way back. 
I'm going in for 2 dyno runs thursday. 
I am a novice at this, what should I look for, what info should I research before tomorrow, any help would be greatly appreciated as I always wish to learn as much as I can
I'm going in for 2 dyno runs thursday. I am a novice at this, what should I look for, what info should I research before tomorrow, any help would be greatly appreciated as I always wish to learn as much as I can
Melting Slicks
Joined: Sep 2003
Posts: 2,458
Likes: 105
From: Northville Michigan
Frank,
Be sure and have your tuner install a bung in your exhaust system. Have them record the air-fuel ratios from 2,500 to 6,500+ rpm. Also, have them record rear wheel torque and rear wheel horsepower at the same engine speeds. These figures should be corrected to a SAE standard.
- Look for air-fuel ratios in the 12.5 to 13.0:1 area.
- Have your tuner eliminate any dips or holes in the horsepower and torque curves. With proper tuning and components your curves should be fairly smooth.
Good luck with your tuning. 
Be sure and have your tuner install a bung in your exhaust system. Have them record the air-fuel ratios from 2,500 to 6,500+ rpm. Also, have them record rear wheel torque and rear wheel horsepower at the same engine speeds. These figures should be corrected to a SAE standard.
- Look for air-fuel ratios in the 12.5 to 13.0:1 area.
- Have your tuner eliminate any dips or holes in the horsepower and torque curves. With proper tuning and components your curves should be fairly smooth.
Good luck with your tuning.