Running 87 Octane in your SS all the time??? - Page 3 - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

strych9 · 06-18-2013, 11:54 AM

Quote:

Originally Posted by KlugSS

I don't pull the fuse. I used hp tuners to copy the high octane timing map over to the low octane table. That way it's always running the timing for higher octane fuel even if it switches maps.

So, in the scenario that Suzook presented (87 octane fuel coming out of a 91/93 octane pump), you're running a high-octane map with low-octane fuel?

You crazy.

willhe64 · 06-18-2013, 11:55 AM

10.7:1 Static compression is way too high on a non overlap cam to run 87.

Static compression is the difference in cylinder volume between the bottom of the stroke and the top. It does not correlate directly to the actual compression your engine is making. You toss in a cam with a lot of duration and overlap and you need to up your compression ratio to compensate for all the loss caused by your piston being on its way back up before both valves are shut and then actually starting to squeeze the air fuel mixture. Then you have volumetric efficiency to factor in. that is how well your engine fills the cylinder on it's suction stroke. Look on comp cams website, once you start getting into the big cams they spec a minimum 11.5:1 static compression.

So you put a big duration cam in the Camaro you may be able to run lower octane fuel as your actual compression may be down. The stock LS3 has no overlap and high volumetric efficiency, gonna squeeze all of that 10.7:1, needs at least 91 to avoid detonation.

You run 89 or 97 and your engine is going to pull timing and add fuel to avoid detonation. This leads to lower performance and mileage.

I have the L9H 6.2 in my truck. I read on another forum (Chevy truck forum) of a user who ran 89 in his truck and recorded the data and then switched to 91. The mileage increase covered the extra cost of the fuel. Not to mention the weeee factor of having peak performance. I ran the same test myself and got the same results. The truck was also noticeably more sluggish. Never ran the test with 87, that would be stupid on a high compression motor.

06-18-2013, 11:56 AM

Quote:

Originally Posted by NoleLife

Side question: Do the 2013's still need a fuse pull when 87 is run? Or was it only a problem on the 10-12s?

I don't see why anything would be different. I don't think it's just a camaro thing either.

06-18-2013, 12:03 PM

Quote:

Originally Posted by strych9

So, in the scenario that Suzook presented (87 octane fuel coming out of a 91/93 octane pump), you're running a high-octane map with low-octane fuel?

You crazy.

It's still on a factory timing table, it's not aggressive at all. I wouldn't worry about it one bit. Besides that, GM had perfected their knock sensors long time ago and I have faith in them. This isn't the only vehicle I do this with. Plus how many people put 87 in then go do WOT passes.

I have never seen enough knock on a factory high octane map when running 87 to care.

strych9 · 06-18-2013, 12:07 PM

Quote:

Originally Posted by KlugSS

It's still on a factory timing table, it's not aggressive at all. I wouldn't worry about it one bit. Besides that, GM had perfected their knock sensors long time ago and I have faith in them. This isn't the only vehicle I do this with. Plus how many people put 87 in then go do WOT passes.

I have never seen enough knock on a factory high octane map when running 87 to care.

Interesting. I'll look into that further.

suzook · 06-18-2013, 12:32 PM

Quote:

Originally Posted by KlugSS

It's still on a factory timing table, it's not aggressive at all. I wouldn't worry about it one bit. Besides that, GM had perfected their knock sensors long time ago and I have faith in them. This isn't the only vehicle I do this with. Plus how many people put 87 in then go do WOT passes.

I have never seen enough knock on a factory high octane map when running 87 to care.

Another reason 87 won't hurt the motor. I'm not "knocking" anyone...that's why we have choices. I haven't seen a motor damaged due to engine knock in many years...it just doesn't happen on modern street cars anymore.

slick rick · 06-18-2013, 12:39 PM

My thoughts are I don't care what other people run in their car.

SS785 · 06-18-2013, 12:59 PM

Quote:

Originally Posted by DRKS1D3

How did I contradict myself? I gave a brief synopsis of the topic and asked what others thought of this member's logic.

Because you didn't have to mention his name in the first place to ask the question. Adding the emoticon for "respect" doesn't mean anything if not long afterwards you bash his logic by saying why buy a 45k car and filling it with 87 and asking for comments. You already know what most are going to respond.

suzook · 06-18-2013, 01:09 PM

Quote:

Originally Posted by SS785

Because you didn't have to mention his name in the first place to ask the question. Adding the emoticon for "respect" doesn't mean anything if not long afterwards you bash his logic by saying why buy a 45k car and filling it with 87 and asking for comments. You already know what most are going to respond.

Its all good. I'm not offended. We all have opinions, and I'm always up for a good debate. After all...its my $...I get to do what I want to with it.

DRKS1D3 · 06-18-2013, 01:58 PM

Quote:

Originally Posted by SS785

Because you didn't have to mention his name in the first place to ask the question. Adding the emoticon for "respect" doesn't mean anything if not long afterwards you bash his logic by saying why buy a 45k car and filling it with 87 and asking for comments. You already know what most are going to respond.

I never bashed his logic or anything of the sort. I asked if others have heard of people strictly using 87 in their SS's. Eh, whatever. No big deal.

suzook · 07-02-2013, 10:29 AM

So I caved and tried putting in 93 and did the fuse pull overnight....I don't notice a difference...is it that noticeable? Idk...seems like a waste.

StevenM · 07-02-2013, 11:24 AM

I've heard / read several threads on whether or not running on 89 or lower will cause harm to the engine and its components and I have seen mixed opinions.

However, does saving $3-$6 each fill up provide enough justification for me to gamble with these types of odds. No....no it does not. I ONLY use Shell V-Power 93 Octane fuel for my 2SS and my 2SS thanks me for that.

suzook · 07-02-2013, 12:04 PM

Quote:

Originally Posted by StevenM

I've heard / read several threads on whether or not running on 89 or lower will cause harm to the engine and its components and I have seen mixed opinions.

However, does saving $3-$6 each fill up provide enough justification for me to gamble with these types of odds. No....no it does not. I ONLY use Shell V-Power 93 Octane fuel for my 2SS and my 2SS thanks me for that.

But I'm wondering if there really is a 30-40 HP difference like people are claiming....I WOULD be able to feel 30-40 HP...5or10...not really.

slick rick · 07-02-2013, 01:29 PM

Quote:

Originally Posted by suzook

But I'm wondering if there really is a 30-40 HP difference like people are claiming....I WOULD be able to feel 30-40 HP...5or10...not really.

you can compare the 0-60 times, there will be a difference. that's partly how the fuse pull mod was verified.

06-18-2013, 11:55 AM	#30
willhe64 Drives: 2012 45th Vert, 2011 4x4, 9sec Vega Join Date: Mar 2012 Location: Canada Posts: 2,188	10.7:1 Static compression is way too high on a non overlap cam to run 87. Static compression is the difference in cylinder volume between the bottom of the stroke and the top. It does not correlate directly to the actual compression your engine is making. You toss in a cam with a lot of duration and overlap and you need to up your compression ratio to compensate for all the loss caused by your piston being on its way back up before both valves are shut and then actually starting to squeeze the air fuel mixture. Then you have volumetric efficiency to factor in. that is how well your engine fills the cylinder on it's suction stroke. Look on comp cams website, once you start getting into the big cams they spec a minimum 11.5:1 static compression. So you put a big duration cam in the Camaro you may be able to run lower octane fuel as your actual compression may be down. The stock LS3 has no overlap and high volumetric efficiency, gonna squeeze all of that 10.7:1, needs at least 91 to avoid detonation. You run 89 or 97 and your engine is going to pull timing and add fuel to avoid detonation. This leads to lower performance and mileage. I have the L9H 6.2 in my truck. I read on another forum (Chevy truck forum) of a user who ran 89 in his truck and recorded the data and then switched to 91. The mileage increase covered the extra cost of the fuel. Not to mention the weeee factor of having peak performance. I ran the same test myself and got the same results. The truck was also noticeably more sluggish. Never ran the test with 87, that would be stupid on a high compression motor. __________________ I feel it only fair to warn you, I have a black belt in CAPS LOCK.

06-18-2013, 12:39 PM	#35
slick rick SoCal Mayhem Drives: 2010 Camaro 1SS/RS Join Date: Aug 2008 Location: Foothill Ranch, CA Posts: 5,488 View My Garage	My thoughts are I don't care what other people run in their car. __________________

07-02-2013, 10:29 AM	#39
suzook Drives: camaro Join Date: May 2013 Location: Stony Brook,NY Posts: 1,756	So I caved and tried putting in 93 and did the fuse pull overnight....I don't notice a difference...is it that noticeable? Idk...seems like a waste. __________________ 2016 2SS,A8,NAV,NPP,MAG Ride,Sunroof Hyperblue/JetBlack

07-02-2013, 11:24 AM	#40
StevenM I love my Camaro 2SS/RS Drives: 2013 Camaro 2SS/RS Join Date: May 2013 Location: Silver Spring, MD Posts: 44 View My Garage	I've heard / read several threads on whether or not running on 89 or lower will cause harm to the engine and its components and I have seen mixed opinions. However, does saving $3-$6 each fill up provide enough justification for me to gamble with these types of odds. No....no it does not. I ONLY use Shell V-Power 93 Octane fuel for my 2SS and my 2SS thanks me for that.