03-11-2024, 07:52 PM | #1 |
Drives: 23 LT1 / 19 Z06 / after 6 5th gens Join Date: Jan 2014
Location: MI
Posts: 1,990
|
5 and 20 pull
If any of you were 5th gen guys and gals, you'd probably remember the old days of fuse 5 and 20 pull overnight to reset the fuel tables.
I recently bought a 23 LT1 with 10k miles. I always run premium in my fun cars. I'm fairly certain the previous owner put in 93, based on how he treated the car, but have no way of knowing for sure. And God knows what the dealer put in it. Any way to "reset" the LT1 and know i'm putting in premium from here on out?
__________________
"Make yourself sheep and the wolves will eat you"
|
03-11-2024, 09:23 PM | #2 |
Drives: 2018 Camaro 2SS A8 Join Date: Jul 2017
Location: East Tennessee
Posts: 11,623
|
Maybe the pro tuners here will know more, but I don't think you can reset fuel table references to force the ECM into the high octane table (happy to be corrected, though). The good news is that the ECM will learn this (from the knock sensors) and move over to the high octane table automatically, the slightly bad news is it may take some time/miles.
__________________
2018 Camaro 2SS — G7E MX0 NPP F55 IO6
735 rwhp | 665 rwtq Magnuson TVS 2300 80mm pulley | Kooks 1 7/8" LT headers | JRE smooth idle terminator cam | LT4 FS & injectors | TSP forged pistons & rods JMS PowerMAX | DSX flex fuel kit | Roto-Fab CAI | Soler 95mm LT5 TB | 1LE wheels | 1LE brakes | BMR rear cradle lockout | JRE custom tune 1100 - 1/30/18 | 2000 - 1/31/18 3000 - 2/06/18 TPW 2/26/18 3400 - 2/19/18 | 3800 - 2/26/18 4300 - 2/27/18 | 4B00 - 3/01/18 4200 - 3/05/18 | 4800 - 3/14/18 5000 - 3/16/18 | 6000 - 3/19/18 |
03-12-2024, 09:15 AM | #3 |
Drives: 23 LT1 / 19 Z06 / after 6 5th gens Join Date: Jan 2014
Location: MI
Posts: 1,990
|
Thank you for your response. I’m hoping so.
__________________
"Make yourself sheep and the wolves will eat you"
|
03-12-2024, 10:22 AM | #4 |
Drives: 2017 Camaro 2SS A8 Join Date: Aug 2018
Location: Petersham MA
Posts: 4,760
|
Arpad is right. Just drive the car with the 93 octane fuel and the engine will slowly add the timing back in (if someone did indeed run 87). Within a full tank of gas you’ll be up to speed I’d say.
__________________
2017 Chevy Camaro 2SS A8 Whipple 3.0, Mast Black Label heads, Fore triple in-tank pumps, 112mm TB, LPE +52% injectors, LPE BB HPFP, 15” conversion 1059 WHP/944 WTQ, 9.48@150
|
03-12-2024, 04:49 PM | #5 |
Drives: 1977 Trans Am, 2024 Camaro 2SS Join Date: Apr 2023
Location: NJ
Posts: 45
|
Having recently come over from a 5th gen as well, I had the same question. I kinda assumed that the updated PCM would have addressed this and it was no longer an issue. So let me add a second question. In my case, the car had 1 mile on it when I test drove it. The fuel gauge was pretty much on E and and low fuel light was on. The salesman had me immediately drive to a gas station and fill it up with 93 octane (using the dealers credit card of course). So my question is what octane fuel does the factory put into a new Camaro SS?
-Ray |
03-12-2024, 06:28 PM | #6 | |
Drives: 2017 Camaro 2SS A8 Join Date: Aug 2018
Location: Petersham MA
Posts: 4,760
|
Quote:
__________________
2017 Chevy Camaro 2SS A8 Whipple 3.0, Mast Black Label heads, Fore triple in-tank pumps, 112mm TB, LPE +52% injectors, LPE BB HPFP, 15” conversion 1059 WHP/944 WTQ, 9.48@150
|
|
03-12-2024, 07:03 PM | #7 |
Drives: 1977 Trans Am, 2024 Camaro 2SS Join Date: Apr 2023
Location: NJ
Posts: 45
|
Well I wouldn't exactly call 11.5:1 a very high compression ratio. In fact it is exactly the same spec as the gen 1 LT-1 (boy, those were octane limited). The gen 2 LT1 had 10.4:1 static compression ratio and did well with it's port fuel injection (mine did great on 93). Octane sensitivity tends to be due to combustion chamber heat transfer rate and the actual dynamic compression ratio as dictated by the camshaft. Our gen V engines have the added benefit of GDI which allows multiple pulses of fuel throughout the cycle to aid in cooling the combustion chamber (a game changer), which also reduces octane sensitivity. This is a wonderful brave new world in which we live in. Some Mazda engines have a static compression ratio of 15:1. Crazy stuff. My point is that octane sensitivity is not dictated by the static compression ratio, but more so by the dynamic compression ratio or actual cylinder pressure AND the heat transfer rate to the coolant/oil/atmosphere. Remember, thermodynamics is our friend.
-Ray |
03-12-2024, 07:05 PM | #8 |
Drives: 23 LT1 / 19 Z06 / after 6 5th gens Join Date: Jan 2014
Location: MI
Posts: 1,990
|
This one I know from the Corvette forums. I’m in a state that offers 93. There are states like CA and CO that’s don’t offer 93, only 91. So my understanding from vette engineers is that the ecu is optimized to 91 octane. That’s my understanding on my LT4
__________________
"Make yourself sheep and the wolves will eat you"
|
03-12-2024, 07:26 PM | #9 | |
Drives: 2017 Camaro 2SS A8 Join Date: Aug 2018
Location: Petersham MA
Posts: 4,760
|
Quote:
False, the LT4 is octane limited even on 93.
__________________
2017 Chevy Camaro 2SS A8 Whipple 3.0, Mast Black Label heads, Fore triple in-tank pumps, 112mm TB, LPE +52% injectors, LPE BB HPFP, 15” conversion 1059 WHP/944 WTQ, 9.48@150
|
|
03-12-2024, 07:36 PM | #10 |
Drives: 23 LT1 / 19 Z06 / after 6 5th gens Join Date: Jan 2014
Location: MI
Posts: 1,990
|
Thanks. I’m going off of memory on a forum from a few years ago. If you know for a fact, then 93 is the answer.
__________________
"Make yourself sheep and the wolves will eat you"
|
03-12-2024, 08:02 PM | #11 |
Drives: 2017 Camaro 2SS A8 Join Date: Aug 2018
Location: Petersham MA
Posts: 4,760
|
Yeah so just to clarify, the car can definitely run fine on 91, but you simply won’t get max power…especially in high heat or heavy load situations. Check out some of KingLT1’s posts in this forum…he tunes them regularly and sees it in the data logs first hand. GM made the car usable on 91 of course….but most of us on this board are power junkies haha.
__________________
2017 Chevy Camaro 2SS A8 Whipple 3.0, Mast Black Label heads, Fore triple in-tank pumps, 112mm TB, LPE +52% injectors, LPE BB HPFP, 15” conversion 1059 WHP/944 WTQ, 9.48@150
|
|
|
Post Reply
|
|
|