New I-6 info...

[HEMIMANN]

Most engines have an ideal timing curve,and advancing past that curve even with higher octane fuel doesn't add squat for power.Engine Masters did a test of this,and they found the ideal timing curve on 87 octane,was pretty well the same ideal timing curve for 91 octane.The hemi might be geared for 89 octane,but the power loss by using 87 octane in a truck 6.4 probably isn't as much as you think. I bet if you had the truck on a dyno and tested rwhp it wouldn't be as big a loss as you think,and i'm not sure the knock sensors would pull as much timing as you think,unless you were at or below sealevel on a 100+ day,and under those circumstances the knock sensors would be pulling timing on 89 to

Agree, of course, my point is I don't like the hunt and search for octane algorithm using knock sensors approach to using 87 octane. My engine noticeably runs smoother on 89 octane, as a number of others have posted as well. I can't audibly hear the knock, but the member who posted the data traces showed it.

The marginal increase in fuel economy and torque comes along for the ride, but that marginal increase is the reason why they designed the default timing for 89 octane instead of 87 octane. No point in debating if they should have done it.

 

[ramffml]

Nissan actually rates their peak HP in their v8 titan differently depending on octane. IIRC it's 390 hp on 87 and 400 on premium.

 

[Riccochet]

Nissan actually rates their peak HP in their v8 titan differently depending on octane. IIRC it's 390 hp on 87 and 400 on premium.

A little bit of timing goes a long way. 10 HP doesn't sound like a lot, but people pay hundreds of dollars for bolt on's just to get an additional 10 HP.

 

[HEMIMANN]

Nissan actually rates their peak HP in their v8 titan differently depending on octane. IIRC it's 390 hp on 87 and 400 on premium.

That's a 2.56% increase. Not much for the money, was my point. But it is a difference.

Same with wife's Mazda CX-5.

 

[ramffml]

That's a 2.56% increase. Not much for the money, was my point. But it is a difference.

Same with wife's Mazda CX-5.

Honestly it feels much more than that with the infamous butt meter.

But anyway, my main reason for running 91 is not for the extra power but just because I cringe everytime I hear it ping. I just want a perfectly tuned, strong running engine. Something that's banging off the knock sensors all the time while towing is not how I want to run my truck.

 

[HEMIMANN]

Honestly it feels much more than that with the infamous butt meter.

But anyway, my main reason for running 91 is not for the extra power but just because I cringe everytime I hear it ping. I just want a perfectly tuned, strong running engine. Something that's banging off the knock sensors all the time while towing is not how I want to run my truck.

It doesn't stumble and sputter either on 89 octane like it does on 87 octane.
I tried 87 octane during the gas price gouge days whenever I wasn't towing. Didn't like how the engine ran one bit.

So, my point is that how FCA set up the dual octane system matters to how the engine runs. Quite a bit.

 

[Kickboxer]

Honestly it feels much more than that with the infamous butt meter.

But anyway, my main reason for running 91 is not for the extra power but just because I cringe everytime I hear it ping. I just want a perfectly tuned, strong running engine. Something that's banging off the knock sensors all the time while towing is not how I want to run my truck.

I've never heard the 5.7 ping even once, 2 different 1500's.
Are you a lead footed type?

I think you are pinging up the wrong tree.........

 

[HEMIMANN]

I've never heard the 5.7 ping even once, 2 different 1500's.
Are you a lead footed type?

I think you are pinging up the wrong tree.........

Knocking can be inaudible. By they time you hear it, it's really doing damage.

 

[Riccochet]

I've never heard the 5.7 ping even once, 2 different 1500's.
Are you a lead footed type?

I think you are pinging up the wrong tree.........

You're not going to hear it, not with variable timing. It's sensing inaudible knock and pulling timing well before you'll hear anything. That's the whole point, to prevent it from getting to point that it causes damage.

 

[Kickboxer]

You're not going to hear it, not with variable timing. It's sensing inaudible knock and pulling timing well before you'll hear anything. That's the whole point, to prevent it from getting to point that it causes damage.

Well, Femll, seems to hear it easily, that is why I call BS.....

 

[ramffml]

I've never heard the 5.7 ping even once, 2 different 1500's.
Are you a lead footed type?

I think you are pinging up the wrong tree.........

You're not going to hear it, not with variable timing. It's sensing inaudible knock and pulling timing well before you'll hear anything. That's the whole point, to prevent it from getting to point that it causes damage.

It's definitely audible. Maybe y'all just have old ears, but it's so obviously there in my truck and also my brother's truck.

The key things to note, it gets worse on lower octane, and higher temps. So try and find another explanation for what I'm hearing then based on those 2 facts, I'm all ears.

Also read the owners manual, "you may hear some amount of pinging which is normal". Obviously they put that in there because it's audible.

 

[Riccochet]

It's definitely audible. Maybe y'all just have old ears, but it's so obviously there in my truck and also my brother's truck.

The key things to note, it gets worse on lower octane, and higher temps. So try and find another explanation for what I'm hearing then based on those 2 facts, I'm all ears.

Also read the owners manual, "you may hear some amount of pinging which is normal". Obviously they put that in there because it's audible.

Don't know. I never run less than 89 top tier fuel, because that's what my manual says to run. And 91 or 93 when towing heavy. It does say I can run 87 with reduced performance....but who wants that? lol I want all the beans!

 

[HEMIMANN]

It's definitely audible. Maybe y'all just have old ears, but it's so obviously there in my truck and also my brother's truck.

The key things to note, it gets worse on lower octane, and higher temps. So try and find another explanation for what I'm hearing then based on those 2 facts, I'm all ears.

Also read the owners manual, "you may hear some amount of pinging which is normal". Obviously they put that in there because it's audible.

Just like Hemi tick is 'normal'.

(for a bad engine design, yeah)

 

[Kickboxer]

It's definitely audible. Maybe y'all just have old ears, but it's so obviously there in my truck and also my brother's truck.

The key things to note, it gets worse on lower octane, and higher temps. So try and find another explanation for what I'm hearing then based on those 2 facts, I'm all ears.

Also read the owners manual, "you may hear some amount of pinging which is normal". Obviously they put that in there because it's audible.

My hearing is very good, and my BS detector is also at a high level.
I call BS, don't keep pushing it...........

 

[ramffml]

My hearing is very good, and my BS detector is also at a high level.
I call BS, don't keep pushing it...........

You're welcome to call it what you like, it doesn't change a thing.