Originally Posted by jz78817

ah, the good old conspiracy theory.

you really are clueless then if you dont think suppliers and manufactuers dont work together on decisions.

11.0:1 is really pretty high for a port-injected engine.

it is??? hmmmm my 1967 Pontiac came 10.75 to 1. so new cars at 11 to 1 are pretty high. .25 percent in 30 years. when you start getting over 13 to 1 then maybe i consider it high. Have worked on some newer blown cars that start at 10 to 1. and Make awsome HP 's and stay reliable. Have built engines upwards of 15 to 1 over the years. Again it comes down to Eliminating Detonation. ITs what can kill a engine fast. Just need to figure out what your combo needs to keep it from detonating. Ok im getting off the topic of additives. Octane use what you need to eliminate detonation(knock) other Additives if you do your maintaince and use decent lubricants and fuels shouldnt need any. Except were recommended like Limited slip additive for a rear end. Fuel system cleaners to his own choice. KNow guys that swear by them know others that never use with no problems.



a bunch of hand-wavey FUD.

Originally Posted by bryan67

Oh and about 25 posts, yea new to this Forum have been on others for years. Sorry i Dont have time to search the Net and find or post on every Forum out there.Ok DL for 1 I've never said higher pump octane will F your car up. look at your pumps reg.mid.prem. range is what 87 to 93 so whats that 6 points of octane rating?? Most standard vehicles wont get damaged by running pump gas.(E-85 Different discussion). Racing fuels also a Different discussion.
Octane rating as said above is Effects Knock of an engine. You want the Definition of Knock look it up. (look under detonation)
As for cars being smarter. They just have more options they can adjust is all. Still a Combustion engine. Looking for same Air/fuel ratios, timing, etc that we have always looked at. Just you may have more cams, variable timing, variable Fuel injection and so on. (again staying away for FI be it turbo or supercharger for this discussion). IF your only concern is Fuel Economy you have to look at the fuel % versus additive % IMO Different gas companies run different %'s What do you think is going to get better mileage more Fuel in the gal. or more additive %. SO without out knowing the exact make up of each. Different blends do get different MPGs. Agree with you there. But dont think its the octane rating thats doing it.
and for E-85 you need roughly a ratio of 1.6 to 1 versus Gasoline so yea you gonna see MPG drop. (imo i wouldnt waste running E-85 on a NA car unless i got no other choice. Now if its Blown,boosted,Bottle fed E-85 has some nice advantages)
I've been talking HP in my posts. And like i have said the lower number octane fuel you can run without detonation occuring, the more power you going to make. Like you say your tuned for 91. Then your wasting money on 93 or higher IMO. Gas around here is .15$ between fuel levels. So your wasting 1-2 dollars per fill up. And if you put lets say 104 in it according to you it should run even better and get better economy right? Bet it dont unless you make some tuning changes. And as you say about cars being smarter. (then why have you needed to get it Tuned??) The computer has only a operating Window it can make changes in. It needs to be tuned to change the parameters of that Window.

Originally Posted by bryan67

Oh an DL yea NP m8 was having a bad day didnt mean to come off harsh. Hope to see you at the MIR race 1st week of May Planning on being there.

Originally Posted by daredevil95

back in the late 90's I had a stock Camaro SS and I put in $40 bucks worth of 104 octane

Originally Posted by daredevil95

I misread the gas pump and put $40 bucks in and it pretty much filled the tank...