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Opinions are one thing facts are another.
Facts can be proven.
Opinions are based on feelings.

You can prove higher octane does not give better power on a stock Forte (such as was proven by currantredGT above).
You can’t prove an opinion or belief that higher octane does give more power.

“Facts don’t care about your opinion.”
-Ben Shapiro
 

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2021 Forte GT- Currant Red - GT2 Package - Ambien Lights
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Opinions are one thing facts are another.
Facts can be proven.
Opinions are based on feelings.

You can prove higher octane does not give better power on a stock Forte (such as was proven by currantredGT above).
You can’t prove an opinion or belief that higher octane does give more power.

“Facts don’t care about your opinion.”
-Ben Shapiro
Ok, controversy aside.

Installing a piggyback like RaceChip, is there any difference with the octane gas used?
 

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Anytime you change the physical engine (raise compression, change cams, etc) or if you change the computer tune, then yes, you will see gains. The new tune makes the power and the higher octane allows those changes to work and prevents them from damaging the engine.

Not sure about RaceChip but quality ones will work. The problem is, there’s is a lot of junk out there too.
 
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Anytime you change the physical engine (raise compression, change cams, etc) or if you change the computer tune, then yes, you will see gains. The new tune makes the power and the higher octane allows those changes to work and prevents them from damaging the engine.

Not sure about RaceChip but quality ones will work. The problem is, there’s is a lot of junk out there too.
As far as I understand there is no tunning with the RaceChip as the JB4 for example. I did get mine to a dyno and it gained about 20+ hp and some 20+ lbs torque. The RaceChip comes with 7 pre-determined maps and I tested it in the higher set with no problems, knocking, or service light. One can feel the difference, though.

Thanks for your input.
 

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I had a 2016 Ford Focus ST and it's power rating with 87 octane was 230 hp. With 93 it was 252 hp. There was no official rating for 91, I did 220 whp on 91 Road Race Engineerings Dynapak (EVO specialist).

87 is minimum octane. I made 201 whp with E20 on the stock tune. 91 octane with the stock wheels was 190 whp, with the Enkeis 195 whp.
 

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I'm not convinced 93 does nothing. With the first tank of 87 I sensed a lot of surging under WOT and watched my ultra-gage as it showed timing go from +20 degrees advance to -2.5 multiple times. Y'all are free to keep doing what you're doing, but I most definitely noticed the difference and will personally be sticking with 93.
 
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Kia recommends 87 Octane for normal driving...it doesn't say anything about "abnormal" driving...:)
 

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I'm not convinced 93 does nothing. With the first tank of 87 I sensed a lot of surging under WOT and watched my ultra-gage as it showed timing go from +20 degrees advance to -2.5 multiple times. Y'all are free to keep doing what you're doing, but I most definitely noticed the difference and will personally be sticking with 93.
Because everybody know the butt-dyno doesn't lie. Who need actual data or proof? The butt-dyno is always right.
 

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I'm not convinced 93 does nothing. With the first tank of 87 I sensed a lot of surging under WOT and watched my ultra-gage as it showed timing go from +20 degrees advance to -2.5 multiple times. Y'all are free to keep doing what you're doing, but I most definitely noticed the difference and will personally be sticking with 93.
only -2.5? :oops:

When I was running 93 octane (all of December until mids of February), the timing advance looked something like this:

83321
83322
83323



Just short intervals snapshots squeezed in together but looks about the same throughout. Since I made the switch to 89 they pretty much look the same...I mostly go by how the car feels. Runs smooth, no rough idling, nor a weird feeling when I go WOT - no difference in how it drives/behaves 89 vs 93. I mean, this is not a race car so I'm not reaching 6k rpms too often. Although, I do have a total of 566-custom runs, 32-0-60 runs, 22-1/8 mi runs, and 14 -1/4 mi runs stored in my dragy account...so I guess I do kinda push her at times lol..........just not everyday. I compare boost levels as well, the car makes same boost (16-17 psi), I'd think that by not running higher octane I'd be seeing less boost, and less power, it still shows 223.9 engine HP (I know its no dyno but hey - pretty cool)...
83325


Im no expert. though lol...I have no idea if those numbers in the above graphs look healthy but that was indeed with 93 octane in the tank.
 

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only -2.5? :oops:

When I was running 93 octane (all of December until mids of February), the timing advance looked something like this:

View attachment 83321 View attachment 83322 View attachment 83323


Just short intervals snapshots squeezed in together but looks about the same throughout. Since I made the switch to 89 they pretty much look the same...I mostly go by how the car feels. Runs smooth, no rough idling, nor a weird feeling when I go WOT - no difference in how it drives/behaves 89 vs 93. I mean, this is not a race car so I'm not reaching 6k rpms too often. Although, I do have a total of 566-custom runs, 32-0-60 runs, 22-1/8 mi runs, and 14 -1/4 mi runs stored in my dragy account...so I guess I do kinda push her at times lol..........just not everyday. I compare boost levels as well, the car makes same boost (16-17 psi), I'd think that by not running higher octane I'd be seeing less boost, and less power, it still shows 223.9 engine HP (I know its no dyno but hey - pretty cool)...
View attachment 83325

Im no expert. though lol...I have no idea if those numbers in the above graphs look healthy but that was indeed with 93 octane in the tank.
This would be great information if there was some context. The timing advance is all over - but is it acceleration or deceleration, where are the shift points, and what is the throttle position?
 

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This would be great information if there was some context. The timing advance is all over - but is it acceleration or deceleration, where are the shift points, and what is the throttle position?
LOL I got none of that info
Let me attach some other snapshots to see if maybe that helps...

83337
83338

^^^ That is back in December. Temps were in the 53-55F, IAT's were in the 80-85F, 93 octane since first week of Dec. I can only tell you that if HP/boost is showing higher it's cuz I was going full throttle. I do not know any more about throttle position nor shift points.

83339
83340

^^^ not too long ago, 89 octane since mids of Feb. Temps were in the 84-87F. IAT's 107-112F.


83341

Last one I can add, this was my last tank of 93. At peak boost levels TA went to -3?
Maybe this wasn't useful at all lol but I tried!
 

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LOL I got none of that info
Let me attach some other snapshots to see if maybe that helps...

View attachment 83337 View attachment 83338
^^^ That is back in December. Temps were in the 53-55F, IAT's were in the 80-85F, 93 octane since first week of Dec. I can only tell you that if HP/boost is showing higher it's cuz I was going full throttle. I do not know any more about throttle position nor shift points.

View attachment 83339 View attachment 83340
^^^ not too long ago, 89 octane since mids of Feb. Temps were in the 84-87F. IAT's 107-112F.


View attachment 83341
Last one I can add, this was my last tank of 93. At peak boost levels TA went to -3?
Maybe this wasn't useful at all lol but I tried!

If we can come up with a direct comparison of 87 Vs 93 (same temps, same throttle use, same street/location) that would be beneficial!

This Graph has has me scratching my head - I want to say this is an idle, to slow take off, to a WOT condition - if so why the sudden drop in timing considering it is when using the highest octane fuel, yet the power stays low (if the time correlation is correct):

83342


I'm reading this as the highest advance is occurring at the lowest power output (maybe idle*) and I'm assuming the advance fluctuations are due to shifting - If you could match the charts like this when using 87-89-93 octane then that would provide a "clearer" picture of what we could expect from the different octanes.

*Old school: On carbureted engines it was normal for timing to be highest at idle because of the ignition vacuum advance...that's why I'm assuming the engine is at idle here.
 

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If we can come up with a direct comparison of 87 Vs 93 (same temps, same throttle use, same street/location) that would be beneficial!

This Graph has has me scratching my head - I want to say this is an idle, to slow take off, to a WOT condition - if so why the sudden drop in timing considering it is when using the highest octane fuel, yet the power stays low (if the time correlation is correct):

View attachment 83342

I'm reading this as the highest advance is occurring at the lowest power output (maybe idle*) and I'm assuming the advance fluctuations are due to shifting - If you could match the charts like this when using 87-89-93 octane then that would provide a "clearer" picture of what we could expect from the different octanes.

*Old school: On carbureted engines it was normal for timing to be highest at idle because of the ignition vacuum advance...that's why I'm assuming the engine is at idle here.
I have NO idea how to interpret that info :LOL: I tried to find something in graphs of what is NORMAL (to help me understand better) but I cannot find anything :( Information all over the place from NA cars and tuned cars but not stock turbo! (admittedly my search was not extensive).

When Chevrasaki mentioned seeing -2.5 at WOT im like...wait a second...cuz I remember seeing negatives while on 93.

I am guessing that those negatives is the "pulling timing"?
The only thing I've been able to find is that negatives (-1,-2) should be at idle? and that it shouldn't be advancing without a load but it SHOULD with a LOAD, and to keep an eye on RPM (load)...its just too much lol :LOL:

I don't mind keeping an eye on it, though, and share more. I don't have the OBDII plug in all the time, I might play with it later on tonight and pay close attention (I have 89 in the tank not that yucky 87 :sneaky: -lol)....then what I can do is fuel up with 93 for 2 tank and see how it compares.

My thinking was that bc the car performs THE SAME that the car is not being negatively affected by the lower octane, bc if it WAS then it would affect performs (by pulling timing, knock,,,reducing boost and the amount of power the engine is able to generate)...but I haven't seen that.
 

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Maybe if you can do three 15 second tests showing TIMING and RPM from idle to 70 MPH on the same road and nearly the same ambient temperature - one test each with 87, 89, and 93 (and the fuel tank would have to be ONLY ONE of the octanes or it will be flawed).

That way we could see the timing difference to get a real idea of any benefit.
 

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*Old school: On carbureted engines it was normal for timing to be highest at idle because of the ignition vacuum advance...that's why I'm assuming the engine is at idle here.
That’s not true. First, you’re assuming the vacuum advance is using full vacuum. However, many systems use ported vacuum that is above the throttle blades where vacuum is low at idle.

Second, overall ignition timing wouldn’t be at its highest because that comes from the inertia mechanical timing. You only get about 3-5 degrees of advance from vacuum. The mechanical system is where you get the most (12+ degrees)
 

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That’s not true. First, you’re assuming the vacuum advance is using full vacuum. However, many systems use ported vacuum that is above the throttle blades where vacuum is low at idle.

Second, overall ignition timing wouldn’t be at its highest because that comes from the inertia mechanical timing. You only get about 3-5 degrees of advance from vacuum. The mechanical system is where you get the most (12+ degrees)
Obviously I can't speak to every engine made but I tuned 60s and 70s Buick Chevy, Ford, MOPAR, Oldsmobile, and Pontiac L6, V6, and V8 engines at dragstrips and I know what I'm talking about.

Your statement about only 3-5 degrees of advance from vacuum is false:

83349


When tuning a big block Buick (61-70 401, 425, 430 or 455) you had to disconnect the vacuum advance hose from the distributor before setting the timing at idle because the vacuum advance was at it's fullest. I tuned HUNDREDS of Buick engines over the years. Only in the later years did they use ported vacuum - and it was often water temperature controlled. The mechanical advance could add 20 degrees more - Best timing for Buick V-8s was 30 degrees advance by 2500 RPM (10 Degrees Initial and 20 degrees mechanical advance) - on the dragstrip WOT meant there was no vacuum advance until you shut it down.

Obviously the highest advance comes when you're driving high speed, engine over 3000 rpm (full mechanical advance), and close the throttle (Plus full vacuum advance). But on these engines the vacuum advanced was kicked in at idle - Factory setting (67 400, 430) initial timing 2.5 degrees BTDC and with the vacuum advance it was 14.5 degrees BTDC. That's pretty advanced. Our engine's timing is controlled by the computer so vacuum advance is moot.

but thanks for your input...

BTW I said I was scratching my head over the graphs...notice the highest ignition advance is @27-28 degrees BTDC BUT the HP requirement is near the lowest on the graph I reposted (post #113)...with your vast knowledge could you explain why? I initially thought it could be due to power-braking but then it makes no sense to drop to -8 to -9 degrees - and the HP output remains the same.
 

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This car heat soaks so easily. This is after sitting in a drive thru for ~7 minutes with no A/C at night in 85F ambient air temps. I wonder where the IAT sensor is located. 149F is hotter than any temp I ever saw from my Cruze or Cooper S.
Automotive lighting Motor vehicle Gauge Steering part Steering wheel
 

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Obviously I can't speak to every engine made but I tuned 60s and 70s Buick Chevy, Ford, MOPAR, Oldsmobile, and Pontiac L6, V6, and V8 engines at dragstrips and I know what I'm talking about.

Your statement about only 3-5 degrees of advance from vacuum is false:

View attachment 83349
That is an adjustable vacuum advance made by MSD. It is not a factory one where vacuum advance is limited. Regardless, even at 12-degrees, that is far from "highest" at idle as you claimed previously.

When tuning a big block Buick (61-70 401, 425, 430 or 455) you had to disconnect the vacuum advance hose from the distributor before setting the timing at idle because the vacuum advance was at it's fullest.
No, you disconnect it because you get SOME advance, at idle just not fullest.

Only in the later years did they use ported vacuum - and it was often water temperature controlled.
There is a lot of debate on that but Holley carbs use ported vacuum high on the metering block specifically for vacuum advance:

The mechanical advance could add 20 degrees more - Best timing for Buick V-8s was 30 degrees advance by 2500 RPM (10 Degrees Initial and 20 degrees mechanical advance) - on the dragstrip WOT meant there was no vacuum advance until you shut it down.
Yes, that's a full 30 deg advance (10 initial + 20 mechnical advance), not the 20-22 deg of vacuum advance (10 initial + 10 to 12 vacuum). Your statement that the engine have full advance at idle is wrong.

but thanks for your input...
 

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This car heat soaks so easily. This is after sitting in a drive thru for ~7 minutes with no A/C at night in 85F ambient air temps. I wonder where the IAT sensor is located. 149F is hotter than any temp I ever saw from my Cruze or Cooper S.
View attachment 83350
The IAT sensor is part of the MAP sensor right there on the intake. The heat soak is not from the intake - it is from the PCV system. 30% of idle intake air is coming from the PCV - where does the PCV air come from - INSIDE THE ENGINE, nice and HOT! That's why as soon as you give it throttle to get going the IATs come down quick - the percentage of cool air increases.

Here's how you can check it: Disconnect the PCV hose from the intake and plug it. Expect the engine to run rough and you may need to keep the throttle open to keep the engine running...but you won't see the "heat soak". Then reconnect the PCV hose. It is normal. A simpler way of checking it is to watch your IATs after starting the engine in the morning - it will take a LOT of idling before the "heat soak" starts because it will take some time for the engine to reach operating temperature. Once it reaches operating temperature you will see your "heat soak".

I don't know about the Cruize and CooperS but on the Cobalt 2.0 2.2 and 2.4 engines they did not use the traditional PCV system. Instead of a PCV valve they used a small metered hole (I think about .0625"/1/16") in the intake that lined up with a literal hole in the engine block. That "PCV" system was not 30% of idle air. There was NO WAY of installing a catch can on it AND the intake would collect a lot of engine oil - I drained my 2.2's intake of 1/2 cup of oil when I removed it! Occasionally in a panic stop my cobalt would shoot white smoke...no telling how much oil the engine ingested...LOL!
 
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