Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums - Camaro5.com
 
Vararam
Go Back   Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums - Camaro5.com > Engine | Drivetrain | Powertrain Technical Discussions > Camaro V8 LS3 / L99 Engine, Exhaust, and Bolt-Ons


Reply
 
Thread Tools
Old 08-25-2009, 08:38 AM   #15
gtbaldini
 
Drives: 2010 Cyber Grey 2SS/RS LS3
Join Date: Jul 2009
Location: Albuquerque
Posts: 153
If you have a custom tune and are happy I wouldn't try this. It may reset the computer and your out a custom tune.
gtbaldini is offline   Reply With Quote
Old 08-25-2009, 09:25 AM   #16
radz28
Petro-sexual
 
radz28's Avatar
 
Drives: Ultra-Grin
Join Date: Oct 2006
Location: Crazy Coast
Posts: 15,156
Quote:
Originally Posted by EAkrish View Post
I am wondering if it will work with a tune also pq. I guess I can try it and let everyone know.....
It'd seem to me that the tune might already compansate for this I'm sure it wouldn't hurt to try though.

Quote:
Originally Posted by EAkrish View Post
Mine was running real good b4 the tune and amazing after the tune. I also did my tb porting b4 I got the tune. Just amazing! I might not even mess with it. I don't want to lose the tune, if that's even possible?
I can't speak for the new PCMs, but the ones that were used with the LS1 cars wouldn't simply default to the OEM tune, because it's my understanding one is actually writing over the OEM tune and the PCM doesn't know the otherwise. I'd disconnect my battery for nights at a time and plug it back in and it was still fine. I'd remove PCM fuses and it was still fine. (FWIW - I could tell the custom tune was in there because I had my idle RPM raised from like 550 to 750, because of my converter, and it remained the same before and after.) That's just what happened to me though, and that wasn't with the current model PCMs...

Quote:
Originally Posted by gtbaldini View Post
If you have a custom tune and are happy I wouldn't try this. It may reset the computer and your out a custom tune.
See above...
__________________

'20 ZL1 Black "Fury"
A10, PDR, Exposed CF Extractor
Magnuson Magnum DI TVS2650R // TooHighPSI Port Injection // FF // Katech Dual In-Tank // Soler 103 // PLM Heat Exchanger // ZLE Cradle bushings // BMR Chassis-Suspension Stuff // aFe Bars // Diode Dynamics LEDs // ACS Composites Guards // CF Dash // Aeroforce // tint // other stuffs
radz28 is offline   Reply With Quote
Old 08-25-2009, 09:33 AM   #17
monza66mo
Driving daily
 
monza66mo's Avatar
 
Drives: '17 2SS
Join Date: May 2009
Location: Missouri
Posts: 79
All the buzz about this so I figured why not try it. I pulled mine last night. No change in my car at all this morning. None. Zero. Zip. Nada. My L99 launched like a rocket from day one so I didn't expect anything.
__________________
Art in Missouri

Last edited by monza66mo; 08-25-2009 at 10:51 AM.
monza66mo is offline   Reply With Quote
Old 08-25-2009, 09:36 AM   #18
radz28
Petro-sexual
 
radz28's Avatar
 
Drives: Ultra-Grin
Join Date: Oct 2006
Location: Crazy Coast
Posts: 15,156
Quote:
Originally Posted by monza66mo View Post
All the buzz about this so I figured why not try it. I pulled mine last night. No change in my car at all. None. Zero. Zip. Nada. But my L99 launched like a rocket from day one so I didn't expect anything.
Too bad, but if there weren't complaints before, there's no loss.

Thanks for sharing
__________________

'20 ZL1 Black "Fury"
A10, PDR, Exposed CF Extractor
Magnuson Magnum DI TVS2650R // TooHighPSI Port Injection // FF // Katech Dual In-Tank // Soler 103 // PLM Heat Exchanger // ZLE Cradle bushings // BMR Chassis-Suspension Stuff // aFe Bars // Diode Dynamics LEDs // ACS Composites Guards // CF Dash // Aeroforce // tint // other stuffs
radz28 is offline   Reply With Quote
Old 08-25-2009, 09:42 AM   #19
Camar0wn3d
formerly "wh0rsep0wer"
 
Camar0wn3d's Avatar
 
Drives: 2016 1SS Summit White
Join Date: Oct 2008
Location: Myrtle Beach, SC
Posts: 489
I tuned in HPTuners on my LS1 and if it is the same for an L99/LS3, this is what happens when you pull the fuses:

There are two tables values used for spark timing - high octane table and low octane table. If you use 93 octane from day one, your computer is using spark timing from the high octane table. If you got a tank of 87 from the dealer, the engine experienced premature detonation and the knock sensors went crazy, and told the computer to use the low octane timing table. What is supposed to happen is after a while of not seeing detonation from the knock sensors, the computer (ECU)tries the high octane spark timing table again. (This doesn't appear to be happening - THIS IS THE PROBLEM!!!!).

The values in the high octane and low octane tables are NON-VOLATILE MEMORY (meaning they are there even if you lose power -like when you do the fuse pull). These tables are usually adjusted when you get a custom tune, and burned into the non-volatile memory. So therefore if you get a custom tune YOU WILL NOT LOSE THESE "TUNED" VALUES with the fuse pull.

What WILL happen with the fuse pull is your volatile memory will be reset. This includes long term + short term fuel trims, knock retard, etc... but what is important in this case is the little parameter that determines which spark table to use will reset...meaning if you were running from the low octane tables before (safe + slow mode), after the fuse pull it will force the computer to try the high octane table again (super giggle fun happy rockin' mode).

However it is important to note that you shouldn't need to try the fuse pull if you've only used high octane gas since getting a custom tune, because burning the tune to the ECU resets all volatile memory. This is why it will go through the idle re-learn process and may run a little weird for the first 20 minutes or so after burning a tune or pulling the fuses.

Pulling the fuses is no different from recovering from a dead battery. The only reason I could see that it would be a problem to pull the fuses is if GM wanted to run diagnostics on the cars with the problem and needed to see the volatile values.
__________________
2010 1SS/RS - CGM/Gray Interior - M6 (SOLD) Kooks 1 7/8" headers, Solo Mach-X, Vararam.

2012 2LS - Black A6 (SOLD)

2016 1SS Summit White A8

Last edited by Camar0wn3d; 08-25-2009 at 09:53 AM.
Camar0wn3d is offline   Reply With Quote
Old 08-25-2009, 09:50 AM   #20
2010 2-Tone


 
Drives: 2010 RY 2SS with Custom Stripes
Join Date: Mar 2009
Location: Jennings, La.
Posts: 2,220
Quote:
Originally Posted by wh0rsep0wer View Post
I tuned in HPTuners on my LS1 and if it is the same for an LS3, this is what happens when you pull the fuses:

There are two tables values used for spark timing - high octane table and low octane table. If you use 93 octane from day one, your computer is using spark timing from the high octane table. If you got a tank of 87 from the dealer, the engine experienced premature detonation and the knock sensors went crazy, and told the computer to use the low octane timing table. What is supposed to happen is after a while of not seeing detonation from the knock sensors, the computer (ECU)tries the high octane spark timing table again. (This doesn't appear to be happening - THIS IS THE PROBLEM!!!!).

The values in the high octane and low octane tables are NON-VOLATILE MEMORY (meaning they are there even if you lose power -like when you do the fuse pull). These tables are usually adjusted when you get a custom tune, and burned into the non-volatile memory. So therefore if you get a custom tune YOU WILL NOT LOSE THESE "TUNED" VALUES with the fuse pull.

What WILL happen with the fuse pull is your volatile memory will be reset. This includes long term + short term fuel trims, knock retard, etc... but what is important in this case is the little parameter that determines which spark table to use will reset...meaning if you were running from the low octane tables before (safe + slow mode), after the fuse pull it will force the computer to try the high octane table again (super giggle fun happy rockin' mode).

However it is important to note that you shouldn't need to try the fuse pull if you've only used high octane gas since getting a custom tune, because burning the tune to the ECU resets all volatile memory. This is why it will go through the idle re-learn process and may run a little weird for the first 20 minutes or so after burning a tune or pulling the fuses.

Pulling the fuses is no different from recovering from a dead battery. The only reason I could see that it would be a problem to pull the fuses is if GM wanted to run diagnostics on the cars with the problem and needed to see the volatile values.
Nice Read!!!!
2010 2-Tone is offline   Reply With Quote
Old 08-25-2009, 10:04 AM   #21
SSOOCH
Camaro SL,UTs
 
SSOOCH's Avatar
 
Drives: 2010 Camaro SS/RS #16429
Join Date: Sep 2006
Location: South Jordan, UT
Posts: 7,358
If you use 91 octane (it's the highest available in my area) will the computer use the high octane tables? Anybody?
__________________
SSOOCH is offline   Reply With Quote
Old 08-25-2009, 10:14 AM   #22
thecamaroguy
 
thecamaroguy's Avatar
 
Drives: 2020 ZLE 67 SS350
Join Date: Jul 2008
Location: Kentucky
Posts: 537
Quote:
Originally Posted by wh0rsep0wer View Post
I tuned in HPTuners on my LS1 and if it is the same for an L99/LS3, this is what happens when you pull the fuses:

There are two tables values used for spark timing - high octane table and low octane table. If you use 93 octane from day one, your computer is using spark timing from the high octane table. If you got a tank of 87 from the dealer, the engine experienced premature detonation and the knock sensors went crazy, and told the computer to use the low octane timing table. What is supposed to happen is after a while of not seeing detonation from the knock sensors, the computer (ECU)tries the high octane spark timing table again. (This doesn't appear to be happening - THIS IS THE PROBLEM!!!!).

The values in the high octane and low octane tables are NON-VOLATILE MEMORY (meaning they are there even if you lose power -like when you do the fuse pull). These tables are usually adjusted when you get a custom tune, and burned into the non-volatile memory. So therefore if you get a custom tune YOU WILL NOT LOSE THESE "TUNED" VALUES with the fuse pull.

What WILL happen with the fuse pull is your volatile memory will be reset. This includes long term + short term fuel trims, knock retard, etc... but what is important in this case is the little parameter that determines which spark table to use will reset...meaning if you were running from the low octane tables before (safe + slow mode), after the fuse pull it will force the computer to try the high octane table again (super giggle fun happy rockin' mode).

However it is important to note that you shouldn't need to try the fuse pull if you've only used high octane gas since getting a custom tune, because burning the tune to the ECU resets all volatile memory. This is why it will go through the idle re-learn process and may run a little weird for the first 20 minutes or so after burning a tune or pulling the fuses.

Pulling the fuses is no different from recovering from a dead battery. The only reason I could see that it would be a problem to pull the fuses is if GM wanted to run diagnostics on the cars with the problem and needed to see the volatile values.
Awesome read! Thanks. This clears things up very nicely!
thecamaroguy is offline   Reply With Quote
Old 08-25-2009, 10:21 AM   #23
gpr
 
Drives: never fast enough
Join Date: Apr 2009
Location: CO
Posts: 59
You only have 91 octane because you live in a higher elevation. the same is true for where i live. You don't need the higher octane at higher elevations. I am gonna go further on this speculation, as i believe what wh0rsep0wer said is correct and the cause for the cars to run better, but since no one has logged data from before and after the fuse pull....

Some are saying they have filled up with premium (91 or 93) gas since day one. Well if you got old gas that wasn't up to standards with the high compression of these engines it will easily cause the engine to knock thus kicking you into the low octane spark table, even though you have filled with premium since day one. Always fill up from a good fuel source that gets fresh fuel often, as it doesn't take long for gas to go bad.
gpr is offline   Reply With Quote
Old 08-25-2009, 11:51 AM   #24
GTAHVIT
Blessed
 
GTAHVIT's Avatar
 
Drives: 2013 Sonic RS MT
Join Date: Dec 2007
Location: Saint Augustine FL
Posts: 28,444
Quote:
Originally Posted by broncosman View Post
I'm at 900 miles now... should be ok for me to do it right? (auto 2SS) and start getting on her a LOT more?
From what we can tell, Yes.

Obviously this isn't a GM approved thing. But there shouldn't be any real risk.

FWIW.
GTAHVIT is offline   Reply With Quote
Old 08-25-2009, 01:15 PM   #25
GMRULZ

 
GMRULZ's Avatar
 
Drives: 2010 SS & 2008 C6
Join Date: Mar 2008
Location: VA
Posts: 1,819
Quote:
Originally Posted by gpr View Post
, but since no one has logged data from before and after the fuse pull....

.
I have dynoed mine before fuse pull 319rwhp 2 pulls back to back, and after fuse pull w/ in 5 minutes of the other 2 runs and picked up 8rwhp, 327rwhp.
__________________
2010 SS L99, 536rwhp 10.843@126.72. Whipple Supercharger stock pulley, ARH 1 7/8 longtubes w/ catted xpipe, magnaflow 3" mufflers, ADM Race CAI, 3:70 gears, lightweight wheels and nitto drag radials. Stock internal L99, stock converter.

Bolt on best before blower 12.22@113.29 w/ nothing but ARH headers, catted x-pipe, ADM CAI and a tune on stock Pzero`s!

Other car 2008 C6 Ls3, z51, A6, Npp Exhaust, best bonestock pass 11.80@118.82, Number 2 on the Corvette Forums Bonestock fastest list..
GMRULZ is offline   Reply With Quote
Old 08-25-2009, 01:26 PM   #26
brandotron
I am the internets.
 
brandotron's Avatar
 
Drives: dangerously
Join Date: May 2009
Location: Redondo Beach, CA
Posts: 12,571
Quote:
Originally Posted by SSOOCH View Post
If you use 91 octane (it's the highest available in my area) will the computer use the high octane tables? Anybody?
I'd also like to hear someone's take on this. 91 is the highest available (other than 100+ race fuel) here in California.
__________________
brandotron is offline   Reply With Quote
Old 08-25-2009, 01:27 PM   #27
gpr
 
Drives: never fast enough
Join Date: Apr 2009
Location: CO
Posts: 59
Quote:
Originally Posted by GMRULZ View Post
I have dynoed mine before fuse pull 319rwhp 2 pulls back to back, and after fuse pull w/ in 5 minutes of the other 2 runs and picked up 8rwhp, 327rwhp.
yes, but why did you pick up 8rwhp? Was it because of colder intake temps, cooler engine, more spark advance from high octane table etc... There could be a million reasons for the increase in power, but if you log the run you will know exactly what is happening with the engine and why you made more power.

Also i could be the variance in the dyno. heck from airing up tires and positioning tires differently on the drum I have seen an 8 hp increase on the dyno.
gpr is offline   Reply With Quote
Old 08-25-2009, 05:57 PM   #28
SGOS252382


 
SGOS252382's Avatar
 
Drives: 2010 Camaro 2SS/RS
Join Date: Mar 2008
Location: S.W. Florida
Posts: 6,294
You guys are crazy. Your car quickly adjusts back to its original settings.

If you want your car to run faster, get some mods and get it tuned by a professional. That will give you real peformance gains that are permanent.
SGOS252382 is offline   Reply With Quote
 
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Fuse Pull: Low Octane Fuel Fix For L99 and LS3. Reset Fuel Map for High Octane Fuel. radz28 Camaro V8 LS3 / L99 Engine, Exhaust, and Bolt-Ons 2837 07-22-2023 09:07 AM
LS3 engine specifications Tran Wiki 3 10-06-2010 10:56 PM
LS3 vs L99? SGOS252382 Camaro V8 LS3 / L99 Engine, Exhaust, and Bolt-Ons 34 09-18-2010 03:55 PM
Check your Order here bvonscott Camaro Price | Ordering | Tracking | Dealers Discussions 665 06-29-2009 01:00 PM
L99 engine specifications Tran Wiki 0 10-19-2008 11:40 AM


All times are GMT -5. The time now is 02:12 PM.


Powered by vBulletin® Version 3.8.9 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.