94 octane vs 87 octane?!?

[Aloicious]

Well to be truthful with you a canned tune isn't something a tuner sets up. Most tuning software comes with pre-loaded files for any given PCM code. These "tunes" are based on bone stock engines and are simply slight adjustments in the fuel and ignition tables and removal of the factory set limiters(vehicle speed, rpms, PATS codes). And unless you take your vehicle to an excellent tuner with a dyno these canned tunes are better than most files that a tuner can draw up based only on numbers. They were written by tuning gurus who spent thousands of hours developing the best possible SAFE parameters. I've got a folder of base tunes I wrote for the most common engines(Ford 4.6 SOHC and Intech mod motors, Triton motors, new Chrysler Hemis and of course the B, D and H Honda motors). I use these as starting points and after learning what the customer has done to their vehicle I adjust where I see fit. I hate canned tunes but since nobody wants to bring their cars to me I have no choice but to send out something I can't test. EVERY tuner will have a clause somewhere stating we are not liable for damage due to a mis-adjusted tune. The reason isn't because we are scared our tunes are fouled, it is because in my experience over half of the customers are lying about their vehicles mileage and the mods performed. If I see a 250k mile B16 with a stock, unported head and exhaust manifold I'll reduce the aggressiveness of the tune. Since those ricers want all the power they can get, they lie to us and we end up sending them a tune with the probability of damaging their junk. If any of you have experience with them you know how weak and pathetic the timing belts are. Well they are supposed to be changed every 80k. The idiots ricing them out NEVER change them. Now I send them an aggressive tune that alters the Vtec ramping and boom, the 250k mile belt pops. Since they are interference motors, the pistons slam the valves and it all snowballs from there. Now they call back and say I owe them an engine because the tune killed their car.

not necessarily, if you're referring to a mail order tune (i.e. places like wheatley and blackbear) as a 'canned tune' then a tuner absolutely does set it up. it may not be a datalogged dyno specific tune, but they will still need to tweak things like the PE delay, shifting parameters, VATS, VSS calibrations, etc, based on the customer's requests usually starting with a base stock tune. as far as 'canned tunes' that come with a tuning suite, its usually software dependent. I have been using EFILive for years and am one of their resellers, and although there are scores of tunes available, both stock and otherwise...I've never seen any general 'lab' tunes that it has with it at purchase, but the tunes that are available as downloads at the holdencrazy repository are not lab created tunes, they're bone stock ones pulled from existing vehicles. so when using those, the tuning does need to be custom taylored at least a little bit for the customer, and each mail order tuner has their own recipe for what they tweak.

I agree that the complexities of tuning a customer's car have it's problems like you stated, I mainly tune my own and my familys/friends vehicles, since my business is educational and journalistic by nature, I prefer to teach people how to tune it themselves. but even with that I have a standard disclaimer that they are responsible for anything they do to their vehicle, but typically for me, its not a problem as the people who are able to purchase the tuning suite and put the time into learning it are a lot more advanced than the guys who never change their timing belts...heh

 

[Tempted]

Absolutely, we(at least those of us who use SCT Advantage), do tweak to the customers request but the tweaks are generally made off of the pre-tuned files that already exist. Those files may be of our own writing or SCTs base. But say you have a 2006 Mustang GT, all stock, I will send an SCT file with the hand held as opposed to my own. Their tune is nearly perfected for a stock vehicle. Now lets say you have a 2006 Mustang GT with a supercharger, cams, headers, injectors and a 4.11 axle ratio. This is where I pull my 3 valve 4.6 forced induction file and make the appropriate changes based on pulley size, available fuel in the area and customers primary application of the vehicle.

 

[Aloicious]

I've never been able to play with SCT, but it sounds pretty similar to what I'm used to.

 

[copernicusd]

i forget where i heard it, on the tv, or magazine, but they said why buy fuel system cleaner, just put in a gallon or so of higher octane gas, something like the fuel system cleaner is higher octane so its basically the same thing
now this was awhile ago, and maybe with the price of gas now, theres no money savings
but occiasinaly when i have $2.00 or so off a gallon i fill up with higher octane, would be nice to know that im just wasting money

 

[Hezsus]

What are peoples opinions of running Methyl Aclohol/Hydrate in the tank, only about 1%. I've used it when I know there is bad gas/water in the tank. can it hurt anything running it al lthe time? I know there is no lubricants in it at all and all that, but thats why only 1%.. mabye to counter the 5-10% ethanol

 

[Tempted]

It hurts the soft fuel system parts.

 

[Aloicious]

methanol, and ethanol are both alcohols, so they don't really cancel anything out. if you're getting water in the system it can help a little with that here and there, but running it all the time is not going to benefit you by mixing it in with the gas.

HOWEVER, using a small alcohol (like methanol) and water mix being injected into the intake tract separately from the fuel as a chemical intercooler CAN provide a good benefit if you need it, like with moderate to high boost...

also realize that different chemicals burn differently that gas, so adding anything on a consistant basis, will alter your A/F ratios....and you may need to alter your tune accordingly (like with water/meth injection)...

here's some stoichiometric ratios for the combustion of different fuels/chemicals so you can see how much they can vary. if you're unfamiliar with stoich ratios, this number is the volume of air needed to but completely burn one unit of fuel, both to completion.

Gasoline -14.7:1
Ethanol - 9:1
Methanol - 6.4:1
Hydrogen - 34:1

I just kinda threw in hydrogen for fun and comparison...they can vary quite a bit, and if you're adding them consistantly, then it's ideal to adjust the tune for them, sometimes you can get away with a small amount added without a tune change, or a little bit for a tank or 2, and just let the O2 sensors try to compensate, like with the government added ethanol, but it's not ideal, and the more 'stuff' you add, the further away from ideal you get. so if you plan on consistantly adding some kind of chemical to the combustion reaction, then you really should be correcting your tune for it.

 

[Tempted]

Alky injection was on every purpose built car we made at the turbo shop I worked at. Suppresses knock, lets us run higher boost without having to use race fuel. It should be noted that it does NOT increase performance by itself but by allowing us to run higher cylinder pressure without retarding the timing/getting spark knock we can raise the boost which does(obviously) increase performance.

 

[Aloicious]

Alky injection was on every purpose built car we made at the turbo shop I worked at. Suppresses knock, lets us run higher boost without having to use race fuel. It should be noted that it does NOT increase performance by itself but by allowing us to run higher cylinder pressure without retarding the timing/getting spark knock we can raise the boost which does(obviously) increase performance.

well put...+1

 

[Hezsus]

methanol, and ethanol are both alcohols, so they don't really cancel anything out. if you're getting water in the system it can help a little with that here and there, but running it all the time is not going to benefit you by mixing it in with the gas.

HOWEVER, using a small alcohol (like methanol) and water mix being injected into the intake tract separately from the fuel as a chemical intercooler CAN provide a good benefit if you need it, like with moderate to high boost...

also realize that different chemicals burn differently that gas, so adding anything on a consistant basis, will alter your A/F ratios....and you may need to alter your tune accordingly (like with water/meth injection)...

here's some stoichiometric ratios for the combustion of different fuels/chemicals so you can see how much they can vary. if you're unfamiliar with stoich ratios, this number is the volume of air needed to but completely burn one unit of fuel, both to completion.

Gasoline -14.7:1
Ethanol - 9:1
Methanol - 6.4:1
Hydrogen - 34:1

I just kinda threw in hydrogen for fun and comparison...they can vary quite a bit, and if you're adding them consistantly, then it's ideal to adjust the tune for them, sometimes you can get away with a small amount added without a tune change, or a little bit for a tank or 2, and just let the O2 sensors try to compensate, like with the government added ethanol, but it's not ideal, and the more 'stuff' you add, the further away from ideal you get. so if you plan on consistantly adding some kind of chemical to the combustion reaction, then you really should be correcting your tune for it.

Thanks! Good explination..I will probably continue to only run it when I get bad gas.