Who is running high octane?

TheAWK

Registered User
hey guys, just thought i would throw a question i have been podering out there.

i had heard that going with a higher octane would give me obviously more performance but also less detonation and other such issues.

any truth to this?

Edit- high octane to me 91, 93, or 95, my car is almost done from a full rebuild

Edit - i am running stock except for 10 over bore, ported heads and gasket to match, and little better exhaust flow.

edit - looking at bigger injectors, more boost, new maf and all that in the future

thanks
 
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I will be running 93, possibly 98 when my build is finished. If you have the need for a higher octane, it is useful. On a daily driven car with few mods, it is probably better, but marginally.
 
For street or strip?


Most of us use 93 octane and Alky injection to boost octane for high boost applications this is for street or strip.

The hardcore guys going to the track use race fuel and an agressive tune.

Most of the Street/Race SC owners at the track leave the alky on to cool down the intake charge and use only a couple of galons of race fuel for a larger safty margin.
 
If pushing more then 15-16 psi then get an alky injection kit to support the boost. Otherwise just stick with 93 octane and less timing.
 
i am going to be running 60 injectors soon enough, is that what you mean by injector kit or is there a specific tune for that?

thansk
 
You can run 93 Octane and be fine, or you could do midgrade and be fine. Upgrade the fuel when you upgrade the car.
 
I plan on running whatever octane is available at the pump plus some Torco Accelerator on race nights. Not looking for maximum performance but just a combo that will give me extra room to not detonate.
 
Around here, I run 92 octane. many places, only 91 octane is available. I'm going to start running E85, that's 105 octane give or take.

Tune for whatever the minimum octane that will be available is.
 
Ford intended for the cars to run on 91 octane plus.

In my own experience, I have found that 91 is a minimum for the car to run completely right. (I have a 10% pulley on the car, so it may be a little less tolerant of low-octane gas than a perfectly stock motor.) On 91, it runs well, and I can floor it anytime with no detonation. On 93, it feels just a hint better. On 89, I can get by, but major boost sometimes results in audible knock, or sometimes the car feels doggy (I think the knock sensor is catching the knock and pulling timing.) On 87, I can loaf around town, but any attempt at hard acceleration makes it knock like crazy.

So I won't run it on 87 unless I have no other choice. I can use 89 if I adjust my driving style a little bit. It's fine on 91. And 93 feels just right.
 
The biggest things with these motors is managing detonation. They detonate, even when you are not hearing it. A little bit of detonation doesn't hurt anything, but allow it to go out of control and it will lead to some damage or worse yet, pre ignition.

Increasing octane alone will not net you more power... just resistance to detonation which means you won't have to back timing off so much, or you can shove more air into the motor safely, or less likely to hit the knock sensor and so on.

I routinely run 91 octane in my car, and go to 94 when I'm heading out to the track. This year, I'm planning to stick with 91 since I've added a few things to the car AND the government's new tax system will increase our fuel cost from $0.90 a litre to $1.30 a litre for everyday 87 octane... so everyone is saying.

Fraser
 
yeah, im not sure how the hst is going to affect fuel prices, but that is a rant for another day. i am going to run 89 or 91 in my car i think,

thanks for the help guys
 
keep in mind also that you must have a good cooling system in these cars to keep temps down. a slightly over heating engine will start to "ping and detonate" on premium gas also.

I have been looking at the snow kit but was wondering if you guys have it on all the time or just when you make good boost or race.
 
I have been looking at the snow kit but was wondering if you guys have it on all the time or just when you make good boost or race.

For my car, I intend to have 2 different tunes. One that is for with Methanol, and one that is for without Methanol. If I ever get switched to a 3 gal tank for the methanol, I may run it all the time. But until then, I basically only use it at the track.

There are some people that have it setup to run all the time, but those people's car needs it for the tune they have. They also don't necessarily daily drive their car. I do.

Note even if you have it on all the time, it's not going to actually use any methanol until you hit the MAFV set points. So it isn't going to come on when you are just driving around, but it will come on say if you floor it to get on a highway. The kit used by the SC crowd is a progressive system that is indexed against the MAF meter. As the maf meter senses more air, you set the Snow system to start the pump at a low voltage. At the snow set point, pump pressure is full, but it's duty cycle is less than 100%. The snow system ramps up the duty cycle as MAF voltage increases until the 100% setpoint.

Thus you set the beginning and ending setpoint based on your car so that the methanol is only running when your car needs it.
 
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Feel like asking a dumb question.

I have a s/c and it is mostly stock, eccept for k&n and the blower has been ported. I have spots of caborn on the exhaust tips. I ussually run 92 or 93, which ever is there, and it has new plugs and wires, Like three weeks old. how can I tune to burn more efficiently? Is this common? Another ?, whats the best way to change the oil pump? Do I have to teardown? If so i will go wild with girdles, deep sump 7 grt pan, High vol pump, and prot the heads?.
Why bother putting it back together stock?
 
I have a s/c and it is mostly stock, eccept for k&n and the blower has been ported. I have spots of caborn on the exhaust tips. I ussually run 92 or 93, which ever is there, and it has new plugs and wires, Like three weeks old. how can I tune to burn more efficiently? Is this common? Another ?, whats the best way to change the oil pump? Do I have to teardown? If so i will go wild with girdles, deep sump 7 grt pan, High vol pump, and prot the heads?.
Why bother putting it back together stock?

Oil pump removal does not need a complete teardown. And every SC i own has carbon soot build up on the exhaust.
 
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