Does 5.0 coyote performance improve with octane?

[robvas]

That said I've never noticed any lack of performance from that. But I only leave the plugs in for a year. Also gets on the O2 sensors, cats, and supposedly fuel injectors but I haven't pulled the injectors to look

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[GrabThatBlue]

I drove my S550 with 87 and 93 and couldnt notice any difference.

 

[HerbB]

A while back VMP did some dyno testing that showed a ~20 horsepower difference between 87 and 93.

That’s what I was looking for. Thanks, rinjdael.

 

[Sinthor 5.56]

coat

Ah, I see. From running too rich/hot. I've never had that happen with cars from using that type of product in the past, but then again, it's not like I used them EVERY time.

 

[Ciulster]

I don't have any instrumented acceleration times but as someone who uses 87 in the winter and for long road trips where loads are low there is actually quite a noticeable difference in power between 87 and 91 and even 94 especially when it's hot out. In the winter it's negligible as you can't get more than 200 ponies to the ground without spinning anyways lol. I have some old timing and knock count data from early this spring from when I was still on 87. Maybe after work today I'll do a pull on the highway and log my timing metrics so we can see the difference.

If you're going off your butt dyno a word of advice is in my experience it usually takes 2 or 3 tanks of 91+ for the engine to "learn" it's okay to give it some more onions and vice versa. The longer you one type of fuel the more the computer tends to ramp up the power or dial it back into a more conservative map.

 

[2024-GT-Vapor Blue]

Agree with those using 93 octane. My performance pack 2024 runs great and that's all I use.

 

[Neggytive]

100 octane would gain power on a gen 4 Coyote as it would still add timing past what it would get on 93. E30 is what, 96-98 octane depending on who you ask? It gains power as well.

Now, is it worth the high price of whatever 100 octane is in your area (it's double the price of 93 here), for a measly 10-15hp?

There is a limit in the tune for how much advance it will give you, advance is not unlimited and as I said above there is a point where you don't get any more torque from adding timing, and the tune is done to comply with EPA standards for emissions. There may be a ton of torque left in there, but the car a car is tuned to pass emissions as well as hold together during the warranty period where the manufacturer eats the cost of repairs.

We all know the Whipple is capable of over 810 HP at the crank

Ford Performance limits their tune using the Whipple hardware to 810 HP

There are limits as to what they can do when the compression ratio is 12.2 to 1, boost likes lower compression but other reason is that 810 HP tune is CARB and 49 state compliant.

I don't know if Whipple is certifying their tunes in excess of the one they supply with the Ford Performance kit to meet EPA/CARB emissions limits

I doubt Ford is creating fuel and timing tables for 100 octane fuel and loading them into a car designed for 93 octane, it is a ton of R&D and compliance work that benefits 1/10th of 1% of the buyers. They are not supporting E85 and that is a fuel available to a lot of people, especially those looking for HP

 

[robvas]

What does Whipple have to do with anything? Talking about stock S650 here, and it will use more timing that 93 will give you.

 

[LouG]

100 octane would gain power on a gen 4 Coyote as it would still add timing past what it would get on 93. E30 is what, 96-98 octane depending on who you ask? It gains power as well.

Now, is it worth the high price of whatever 100 octane is in your area (it's double the price of 93 here), for a measly 10-15hp?

The ignition map is the max timing the ECU will allow under ideal conditions. Raising octane over the Ford spec won't make it add more timing. But if the map is altered to allow more timing advance for 100 octane or E85, etc, it will produce more power to a point.

 

[robvas]

The ignition map is the max timing the ECU will allow under ideal conditions. Raising octane over the Ford spec won't make it add more timing. But if the map is altered to allow more timing advance for 100 octane or E85, etc, it will produce more power to a point.

Again, the factory map allows more timing on higher than 93...

 

[LouG]

Again, the factory map allows more timing on higher than 93...

I'll take your word for it, but that's a very unusual thing on modern cars.

 

[ChitownStang]

I don't thin

Again, the factory map allows more timing on higher than 93...

Thats not right from everything i have read. You have to tune for more power. You will get your consistent max power from E30 but not more than the tune will allow.

 

[CRC123]

From the 2026 Mustang manual …For best overall vehicle and engine performance, premium fuel with an octane rating of 91 or higher is recommended

 

[robvas]

From the 2026 Mustang manual …For best overall vehicle and engine performance, premium fuel with an octane rating of 91 or higher is recommended

 

[Junkyard Dog]

I don't thin

Thats not right from everything i have read. You have to tune for more power. You will get your consistent max power from E30 but not more than the tune will allow.

Right, because the ecu is pulling timing in certain conditions, but with E30, it does not have to. In comparison, then, the ECU is advancing timing during those conditions when E30 is used, when it would not if 93 octane were being used.

I think you are both saying the same thing but still arguing with each other.

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