Putting higher than 93 octane in a stock non tuned SS?

[White14SS]

Originally Posted by Neuf Cruz

OP is stock!
Not bashing but I think tuning your car to run on basically "race Gas" for under 500hp is really not worth it. Many Mods you can do on pump gas to achieve this.

I already did the basic bolt ons, just want to do heads and cam now.

[White14SS]

Originally Posted by rfopt

Do you know what your WOT air fuel ratio is roughly? Was the sensor that recorded the air fuel ratio placed at the tailpipe?

12.0-12.4

[White14SS]

Originally Posted by el ess A

Roll that dice. Octane ratings for pump race gas are AVERAGE. So the gas you used one day, may have better octane rating than the next. Thus you just inserted a variable into the equation, risking problems. Use only enough octane to keep your car from knocking. Anything more is a waste. In fact you can actually lose power if your octane is too high.

I would never recommending tuning for a particular grade of racing fuel like that, but hey, it's your grenade.

For stock, and if you have 93 pump gas plentiful around you, tune for that and call it a day. If you want more, put headers on it. From a cost standpoint, considering that the Sunoco at 7 bucks/gal is about double what you pay, you could pay for those headers quickly than "renting" the HP through the gas. Using 93 and at say, 20 mpg, the headers could pay for themselves in about 8500 miles.

I already did intake headers and have the npp. I made 419 on 93 and 447 on 100. Doing heads and cam to try for 500. Like I said the 7 bucks doesn't bother me since it's not my dd. I just hit 2000 miles. No winter no rain no work no anywhere really but weekend cruising.

[Bodywerks]

Originally Posted by el ess A

Roll that dice. Octane ratings for pump race gas are AVERAGE. So the gas you used one day, may have better octane rating than the next. Thus you just inserted a variable into the equation, risking problems. Use only enough octane to keep your car from knocking. Anything more is a waste. In fact you can actually lose power if your octane is too high.

I would never recommending tuning for a particular grade of racing fuel like that, but hey, it's your grenade.

For stock, and if you have 93 pump gas plentiful around you, tune for that and call it a day. If you want more, put headers on it. From a cost standpoint, considering that the Sunoco at 7 bucks/gal is about double what you pay, you could pay for those headers quickly than "renting" the HP through the gas. Using 93 and at say, 20 mpg, the headers could pay for themselves in about 8500 miles.

I'd control my octane with Torco. Not race gas. That way I wouldn't have to worry about finding a 100 octane pump if I decided to do a road trip.
I already have intake and headers, soon heads and cam. If I can bump up the compression, bump octane up to 95 or 100, and gain yet another 20+rwhp, it's worth it for me, too, as this is not my only vehicle.

[SnowyCamaro]

Octane increase will not create any more power then it is designed to by the tune. Our cars are able to modify timing to achieve the best efficiency. Ie if you put 94 octane in it it will advance timing to better use the fuel, the reverse happens with poorer fuel to prevent engine knock. However, I do not know the limits of this system, if you were to put in over 100 octane would the car advance timing enough, its all how its designed, you can only advance timing so far before running higher octane requires more compression. So if gm designed the car to perform at its peak timing and compression with premium or 93-94 then no you will not see any benefit if they did design it to push timing for a large range of fuels then maybe you will. Its hard to say without being the engineer in charge of fuel mapping. But this is as far as i understand it from my engineering point of view. Also if you expect to feel a large difference between fuels, don't hold your breath, without a tune not a huge deal. It may start a little better, I've always found in the winter my car starts better with 94, but that's more due to the additives in more expensive fuel than the octane increase.

I don't know about race gas, I am sure its similar, but I've run aviation gas in my dirtbikes but it can damage the motor. (It is an improvement, then again i changed compression to get that power) Aviation gas has much less additives and strips lubrication away from piston rings that are not designed to handle it (at least thats what i was told). Its partially related to the temp it burns at as well. Av gas is also leaded, so not too good for cats. On a final note, race gas may not completely burn in the combustion chamber (this comes back to what gm designed for) if it can't push timing far enough. If you run rich exhaust (exhaust with unburned hydrocarbons)through your cats, you will shorten their life.

Not saying don't do it... just be educated about it before you do.