87 Octane Tune: Mission Accomplished!
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87 Octane Tune: Mission Accomplished!
Final details in post #48!
I was talking to Lew this morning about tunes and various other things, and we began to discuss the idea of an 87 octane tune. The idea is, to see how much power we're and MPG we'd be giving up, due to the decreased timing needed for an 87 tune...At least one that doesn't knock.
Has anyone tried this? At this point, it's just an experiment to see if the $3.00 per tank savings is nullified by worse fuel economy and lack of power. On the other hand, if it can be made to run good with little or no KR, it might be a nice tune to have for long trips where power isn't the most important thing.
Any thoughts?
I was talking to Lew this morning about tunes and various other things, and we began to discuss the idea of an 87 octane tune. The idea is, to see how much power we're and MPG we'd be giving up, due to the decreased timing needed for an 87 tune...At least one that doesn't knock.
Has anyone tried this? At this point, it's just an experiment to see if the $3.00 per tank savings is nullified by worse fuel economy and lack of power. On the other hand, if it can be made to run good with little or no KR, it might be a nice tune to have for long trips where power isn't the most important thing.
Any thoughts?
Last edited by LS1 Racing; 02-10-2011 at 03:08 PM.
#2
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if your properly tuned (retard timing) your mileage shouldn't change at all. You will lose a good amount of hp though, Probably 15-20hp.
Just to drive it home, there are plenty of LS based engines that come with 87 octane tunes, I.E. G8GT, trucks, etc. Again there is no loss in mileage.
Just to drive it home, there are plenty of LS based engines that come with 87 octane tunes, I.E. G8GT, trucks, etc. Again there is no loss in mileage.
Last edited by JDMC5; 01-24-2011 at 01:45 PM.
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The power loss would be worthwhile to me on long trips, assuming you're correct on not losing any MPG. It would be pretty sweet to be able to flash to that whenever necessary. Or, if we start getting raped on gasoline prices again.
#5
Some company was doing 87 octane tunes. I forgot who it was. I think it had power gains, as well, I don't remember, it's been a while since I've seen it.
EDIT: I believe it was Overkill.
EDIT: I believe it was Overkill.
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i would be interested in it to use over winter. im not going to be racing during the winter season so why use more expensive gas when your not using it like you would be in the summer
#7
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It's 3 bucks Its really that big of a deal to men personally I'm all for maximizing efficiency but it's a v8 you knew the deal why you
bought it, just saying I drove
from Ohio to Vegas and
stopped for gas six times so it's just not worth it all take all the power I can get
bought it, just saying I drove
from Ohio to Vegas and
stopped for gas six times so it's just not worth it all take all the power I can get
Trending Topics
#8
- Increased Gas Mileage through fuel and timing advance revisions, DOD revisions and transmission retuning (Fueling has been reworked to eliminate lean and rich transitions, making fueling more consistent. Fueling has been leaned out @ full throttle)
- Increased Performance & Horsepower Timing advance adn fueling optimized for power and KR reduction under heavy throttle. Transmission "skip-shifts" enabled! (Expect to see anywhere between 5-20HP or more depending on modifications and mechanical condition)
- Reduced Likelihood of Transmission Issues Factory calibrations heavily revised, coding "cleanup". More progressive tables, higher fluid pressures, revised "torque management" reduces slippage, shudders.
- Lower engine temperature Fan settings recalibrated for factory thermostat
- Speed Limiters removed adn Rev Limiters raised
- Improved driveability through extensive transmission shift retuning and improved throttle response
- Will not affect emissions testing
- Runs on 87 octane in most vehicles with full performance benefits (If you have intake/exhaust modifications, you should be able to run 87 octane and achieve full performance benefits. If you have a stock vehicle, you may have better performance under heavy throttle with a mid-range 89 octane. Remember that octane refers to the gasoline's resistance to ignite, and has nothing to do with the "quality" of the gasoline)
- Timing Advance table in this PCM is highly modified over stock, it is designed to increase spark where available to increase throttle response and gas mileage significantly. At full throttle, your timing will be in the mid-gigh 20s, optimal for making great power on regular octane fuel. This is an increase of up to 5* over stock.
- DOD Factory settings are fairly tame and have been heavily revised. In 3rd and 4th gear, under cruise conditions at light throttle, you will find DOD activates sooner and remains engaged longer as you lightly accelerate. These activation and deactivation points have been carefully chosen not to bog down the engine when climbing hills. Timing advance in DOD have been heavily revised also, this not only increases engine efficiency while in DOD but also makes the engine much smoother. Maximum run-time has also been increased from 8 minutes to 10. There is no speed limit on DOD, it will activate at 150mph if conditions permit it!
- Thermostat We recommend to keep the stock thermostat. The car will run cooler, the low speed fans will engage at around 195* and the high speed fans just over 200*. An aftermarket cooler temperature thermostat cna be run, however the computer cannot be reprogrammed to allow the fans to come on at any cooler temperature. The reason being is the factory computer only controls the fans from 192*F and hotter. The low speed fans will also stay on for 120 seconds at key-off at temperatures at or above when the cooling fans normally run.
- Skipshifts Torque converter lockup will not engage until a higher road speed is reached, which greatly reduces city driving bogging. At full throttle up to 40mph, the transmission will downshift into 1st gear , on the highway, you'll find it even more noticeable as the transmission will downshift into 2nd gear anytime up to 90mph if given full throttle. GXP owners with TAP shift, you will love the changes that have been made! First off you'll notice the transmission responds quicker to your inputs, with crisp quick shifts. You'll also notice that the torque converter ("overdrive") will not engage, even at highway speeds while in TAP shift mode, which makes the vehicle much more responsive to your right foot inputs. When you're done playing, switch back to normal drive mode and the overdrive will re-engage.
- Air Conditioning is disabled over 3500rpm, to prevent wear on the compressor unit and regain horsepower that is lost in driving the unit. You may feel you're A/C isn't blowing cold if into the throttle for an extended period of time, this is normal and your A/C will re-engage once you lift off the throttle
- Increased Performance & Horsepower Timing advance adn fueling optimized for power and KR reduction under heavy throttle. Transmission "skip-shifts" enabled! (Expect to see anywhere between 5-20HP or more depending on modifications and mechanical condition)
- Reduced Likelihood of Transmission Issues Factory calibrations heavily revised, coding "cleanup". More progressive tables, higher fluid pressures, revised "torque management" reduces slippage, shudders.
- Lower engine temperature Fan settings recalibrated for factory thermostat
- Speed Limiters removed adn Rev Limiters raised
- Improved driveability through extensive transmission shift retuning and improved throttle response
- Will not affect emissions testing
- Runs on 87 octane in most vehicles with full performance benefits (If you have intake/exhaust modifications, you should be able to run 87 octane and achieve full performance benefits. If you have a stock vehicle, you may have better performance under heavy throttle with a mid-range 89 octane. Remember that octane refers to the gasoline's resistance to ignite, and has nothing to do with the "quality" of the gasoline)
- Timing Advance table in this PCM is highly modified over stock, it is designed to increase spark where available to increase throttle response and gas mileage significantly. At full throttle, your timing will be in the mid-gigh 20s, optimal for making great power on regular octane fuel. This is an increase of up to 5* over stock.
- DOD Factory settings are fairly tame and have been heavily revised. In 3rd and 4th gear, under cruise conditions at light throttle, you will find DOD activates sooner and remains engaged longer as you lightly accelerate. These activation and deactivation points have been carefully chosen not to bog down the engine when climbing hills. Timing advance in DOD have been heavily revised also, this not only increases engine efficiency while in DOD but also makes the engine much smoother. Maximum run-time has also been increased from 8 minutes to 10. There is no speed limit on DOD, it will activate at 150mph if conditions permit it!
- Thermostat We recommend to keep the stock thermostat. The car will run cooler, the low speed fans will engage at around 195* and the high speed fans just over 200*. An aftermarket cooler temperature thermostat cna be run, however the computer cannot be reprogrammed to allow the fans to come on at any cooler temperature. The reason being is the factory computer only controls the fans from 192*F and hotter. The low speed fans will also stay on for 120 seconds at key-off at temperatures at or above when the cooling fans normally run.
- Skipshifts Torque converter lockup will not engage until a higher road speed is reached, which greatly reduces city driving bogging. At full throttle up to 40mph, the transmission will downshift into 1st gear , on the highway, you'll find it even more noticeable as the transmission will downshift into 2nd gear anytime up to 90mph if given full throttle. GXP owners with TAP shift, you will love the changes that have been made! First off you'll notice the transmission responds quicker to your inputs, with crisp quick shifts. You'll also notice that the torque converter ("overdrive") will not engage, even at highway speeds while in TAP shift mode, which makes the vehicle much more responsive to your right foot inputs. When you're done playing, switch back to normal drive mode and the overdrive will re-engage.
- Air Conditioning is disabled over 3500rpm, to prevent wear on the compressor unit and regain horsepower that is lost in driving the unit. You may feel you're A/C isn't blowing cold if into the throttle for an extended period of time, this is normal and your A/C will re-engage once you lift off the throttle
I don't know if they still do this.
#9
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It's 3 bucks Its really that big of a deal to men personally I'm all for maximizing efficiency but it's a v8 you knew the deal why you
bought it, just saying I drove
from Ohio to Vegas and
stopped for gas six times so it's just not worth it all take all the power I can get
bought it, just saying I drove
from Ohio to Vegas and
stopped for gas six times so it's just not worth it all take all the power I can get
Of course, the only way this makes sense is if there's no hit to fuel economy. If there's even a small drop in MPG, then this is a stupid idea, and I'll be the first to admit it!
Anyway, I'll be filling up with 87 sometime in the next couple of weeks and logging the results. Once I've done that, I'll send them off to Lew to see what he can do about coming up with a tune that fits.
In the meantime, I'll try to get to a track so I can get a few baseline runs on 91 octane, so we can compare. Obviously, a dyno makes more sense, but there aren't any within an hour's drive of where I live.
#10
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I run 89 octane in mine full-time and it runs great. Pretty consistent 16mpg with a LOT of stop-n-go traffic in the city, then usually 21-23hwy depending on my speed. Seems pretty on par with what I've read.
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They're supposed to be okay to run on 87 or 89, but they knock a lot, resulting in near-constant KR. Most likely, you won't hear the knock, but you'll definitely see it if you hook a scan gauge up to it.
Personally, I think any KR is bad, because it means some knock is still occurring. Fortunately, the LS motors don't normally blow head gaskets, so that isn't s major problem. However, knock is still hard on pistons, rods, and cranks, and I would do anything I can to prevent it.
That's the other criteria for this tune: Little or no KR.
Personally, I think any KR is bad, because it means some knock is still occurring. Fortunately, the LS motors don't normally blow head gaskets, so that isn't s major problem. However, knock is still hard on pistons, rods, and cranks, and I would do anything I can to prevent it.
That's the other criteria for this tune: Little or no KR.
#13
Well if you are only paying 3 bucks a tank extra x4 tanks a week... seems to be a pretty cheap grin factor.
Here its like 8 bucks a tank more and I wouldn`t even think twice about loosing that grin factor any time soon...
Here its like 8 bucks a tank more and I wouldn`t even think twice about loosing that grin factor any time soon...
#14
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yeah, I already do all of that, and more.... except for the tranny shifting/line pressure changes, since there's no tcm/tranny support with the diablo stuff yet....
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06MonteSS / DiabLew Tune
2014 Camaro 2SS/RS - LS3, 6-speed manual, short-throw performance shifter, NPP dual-mode performance exhaust, 1LE front splitter, ZL1 rockers, Z28 Rear Spoiler, all paint-matched Red Rock Metallic, BMR strut tower brace, Cold Air Inductions cold air intake, Apex Motorsports, Inc. catch-can, Custom DiabLew Tune
www.diablewtune.com -- www.diablocustomtune.com -- www.diablocustomtunegm.com
#16
I'm interested in more details....
Although i would love to have my GXP fully tuned/modded, its not ideal for my situation. I travel and I'm usually not always looking for suburban combat. Locally they charge a fortune for a dyno tune and thats still some guy off the internet in a hot rod garage messing with my daily driver.
I'm looking for better power without any sacrifice to fuel mpg... on a budget.
Although i would love to have my GXP fully tuned/modded, its not ideal for my situation. I travel and I'm usually not always looking for suburban combat. Locally they charge a fortune for a dyno tune and thats still some guy off the internet in a hot rod garage messing with my daily driver.
I'm looking for better power without any sacrifice to fuel mpg... on a budget.
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I thought less timing = less MPG and power? I'm assuming total timing would need to be reduced because, when I tried 87 and monitored KR, I was seeing constant 5-6 degrees of KR at cruise in 4th at 2000 RPMs. Wouldn't the reduced timing to eliminate the knock also cost MPG?
The power loss would be worthwhile to me on long trips, assuming you're correct on not losing any MPG. It would be pretty sweet to be able to flash to that whenever necessary. Or, if we start getting raped on gasoline prices again.
The power loss would be worthwhile to me on long trips, assuming you're correct on not losing any MPG. It would be pretty sweet to be able to flash to that whenever necessary. Or, if we start getting raped on gasoline prices again.
I'm trying not to get into theory and just make it simple. I can post more technical stuff if you guys want.
#18
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I'm interested in more details....
Although i would love to have my GXP fully tuned/modded, its not ideal for my situation. I travel and I'm usually not always looking for suburban combat. Locally they charge a fortune for a dyno tune and thats still some guy off the internet in a hot rod garage messing with my daily driver.
I'm looking for better power without any sacrifice to fuel mpg... on a budget.
Although i would love to have my GXP fully tuned/modded, its not ideal for my situation. I travel and I'm usually not always looking for suburban combat. Locally they charge a fortune for a dyno tune and thats still some guy off the internet in a hot rod garage messing with my daily driver.
I'm looking for better power without any sacrifice to fuel mpg... on a budget.
#19
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Yes, by retarding timing I mean global retard probably 4-6 degrees. Less timing (than optimum) does = less power and mpg if you are talking with respect to one specific octane. Now, by lowering the octane you've now lowered the required ignition lead for optimal power, even at part throttle. Your engine doesn't need high octane at low cylinder pressures (obviously) so all were doing is optimizing the timing for the low octane.
I'm trying not to get into theory and just make it simple. I can post more technical stuff if you guys want.
I'm trying not to get into theory and just make it simple. I can post more technical stuff if you guys want.
#20
LS1Tech Sponsor
higher octane, can advance the timing more...
lower octane, have to reduce it...
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06MonteSS / DiabLew Tune
2014 Camaro 2SS/RS - LS3, 6-speed manual, short-throw performance shifter, NPP dual-mode performance exhaust, 1LE front splitter, ZL1 rockers, Z28 Rear Spoiler, all paint-matched Red Rock Metallic, BMR strut tower brace, Cold Air Inductions cold air intake, Apex Motorsports, Inc. catch-can, Custom DiabLew Tune
www.diablewtune.com -- www.diablocustomtune.com -- www.diablocustomtunegm.com
06MonteSS / DiabLew Tune
2014 Camaro 2SS/RS - LS3, 6-speed manual, short-throw performance shifter, NPP dual-mode performance exhaust, 1LE front splitter, ZL1 rockers, Z28 Rear Spoiler, all paint-matched Red Rock Metallic, BMR strut tower brace, Cold Air Inductions cold air intake, Apex Motorsports, Inc. catch-can, Custom DiabLew Tune
www.diablewtune.com -- www.diablocustomtune.com -- www.diablocustomtunegm.com