TO AWSUM
Ford GT Owner
Our district's Congressman is attempting to get ethanol gasoline banned in FL. Hope he is successful. Can't wait.
Question regarding fuel
- Thread starter 6s219
- Start date
33Bravo
GT Owner
Hi Jason
I believe non-oxy fuel as its called here in Minnesota is the non-ethanol gas.
Question to all, would 93 octane fuel with ethanol, or 91 octane fuel without ethanol be better for the FGT?
THanks
I believe non-oxy fuel as its called here in Minnesota is the non-ethanol gas.
Question to all, would 93 octane fuel with ethanol, or 91 octane fuel without ethanol be better for the FGT?
THanks
Indy GT
Yea, I got one...too
Jason, I concur with the above from 33Bravo. If one refers to "non-oxy" gasoline, IMO that is gasoline which has not been blended with any alcohol extender.
The 93 octane with ethanol vs the 91 octane without is another very good question. Here are my thoughts.
Since our FGT engine was certified in all states and some states only offer the purchase of 91 octane unleaded premium fuel, the engine only NEEDS 91 octane to prevent detonation damage. Note the 91+ octane sticker under our fuel door. Owners running higher octane fuels if they are available in their state are fine with that too. Anything over a base level of 91 octane is OK. Note running 93 octane gasoline (this higher octane rating brought to the fuel by the addition of some amount of ethanol) does the engine no good (or harm), costs the owner more money (only if 91 octane is available in the operating state and costs less, if not, it is what it is) but lowers the amount of energy the fuel brings to the engine. Thus you need more of this oxyginated fuel for a given power output and overall your gasoline mileage (if any FGT owner really cares) will go down.
My advice given the choice of 91 no alcohol vs 93 with alcohol is to always select the no alcohol fuel as long as it has a rating of 91 octane or above.
33Bravo
GT Owner
Makes sense.
In my case - I have always (ok almost always) run no alcohol.
My engine is mildly upgraded (throttle body, pulley, sct tune, headers). At what point of performance upgrades do you need to switch to the 93 octane?
In my case - I have always (ok almost always) run no alcohol.
My engine is mildly upgraded (throttle body, pulley, sct tune, headers). At what point of performance upgrades do you need to switch to the 93 octane?
Superfly
HERITAGE GT OWNER
Around my place, I have a choice of 91 Octane "Gas" or 94 Octane E10 "Ethanol blended Gas". Torrie, whose opinion is like gold to me, suggests I'm better off running the 94 Octane ethanol blend with a 93 tune on my programmer rather than the 91 tune with 91 gas. So, that's what I'll be doing next year.
:banana
:banana
Indy GT
Yea, I got one...too
Of the four listed engine modifications, the pulley and sct tune will alter engine octane requirements. The smaller pulley results in higher blower speed increasing upper deck pressure (intake pressure and ultimately combustion pressures) and the tune alters spark advance. Both are predicated on the tuner expecting the engine to be given a certain octane level fuel. I would stick with the recommendations which accompanied the sct tune as they know how far out on the spark advance their tune goes. Most "tunes" have associated with them an octane fuel requirement.
93 octane fuel is probably a good bet to run with these alterations.
93 octane fuel is probably a good bet to run with these alterations.
Indy GT
Yea, I got one...too
I certainly agree and that famlies with my earlier statements. Due to the "tune" Torrie has added to your ECU, your engine now NEEDS to have 93 octane fuel (due to the spark advance curve in the new aftermarket tune). This is different now from a stock FGT engine with an OE Ford tune which requires 91+ octane fuel.
So you would be foolish to run the engine on a fuel octane (91 in this case) below which it NEEDS per the spark advance logic in the ECU.
Superfly
HERITAGE GT OWNER
Agreed, that would be foolish if I ran the 93 tune with 91 fuel. BUT, I got 3 extra tune files with the programmer (the stock factory tune, plus a 91, 93 and 100 tune). I've been running the 91 tune with the pully and 91 gas. I will run the first 2 tanks next spring with the 91 tune but go to the 94 gas, and then when I'm fairly certain the 94 gas is all that's left in the tank, I'll change to the 93 tune and run the 94 gas the rest of the year. That's what I had said, but I'm sorry if that wasn't clearer in the post.
t32b
Verde
Silly question likely best answered by Chip. It Citgo gas sold on the east coast the same as Chevron sold on the west? Or are they unrelated?
Additional question is that there is a local 76 station here in the Bay Area that also has two pumps selling Sunoco 100 race gas. Is that mixed with ethanol? I use a 4:1 mix of 91 (the max standard octane sold in CA) and 100 octane to 'bring' my average octane up a bit, to say 93 or so which is optimum for my Porsche whenever I get the chance.
Thanks,
Rich
Additional question is that there is a local 76 station here in the Bay Area that also has two pumps selling Sunoco 100 race gas. Is that mixed with ethanol? I use a 4:1 mix of 91 (the max standard octane sold in CA) and 100 octane to 'bring' my average octane up a bit, to say 93 or so which is optimum for my Porsche whenever I get the chance.
Thanks,
Rich
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Hahaha, Rich, sounds like you and Black Ice are both into mixing your own blend.... You do it on Union 76, while Ice likes his Sherwin Williams...
GTED
GTED
2112
Blue/white 06'
Isn't CITGO the state owned distribution of product for Venezuela? ie Hugo Chavez, known pal of Sean Penn?
2112
Blue/white 06'
BlackICE
GT Owner
Indy GT
Yea, I got one...too
Rich, while I will certainly defer to Chip if he has additional input, why or how do you think Chip would know how Sun Oil Company (Sunoco) achieves their octane rating of 100 in their racing gasoline sold in San Francisco? The oil companies have a multitude of blending agents they CAN use to achieve a certain level of octane. They have to know this information to continue to offer product when and if product shortages arise. And since this is "racing" gasoline, this may give the blender an even broader latitude on "non EPA" approved blending agents to use.
The "Sherwin-Williams" octane enhancer as mentioned above (i.e. Toluene or methyl benzene) has a research octane rating of 120, so it is possible to blend an unleaded gasoline without alcohol (which again has a research octane rating of 107) and achieve a 100 octane rating. Also of interest Toluene has an energy density of 18,487 BTU/Lbm much closer to that of straight gasoline and considerably larger than that of ethanol. So the resulting blend with toluene will have a higher energy content than using alcohol. But it most probably COSTS more to use toluene as a blending agent relative to others.
Based on the prevailing economics at the time the batch is to be blended, Sunoco may choose formulation X which costs them less at that time. But say for instance one of the lower cost blending agents is not available or has spiked in cost due to a shortage, the next Sunoco batch may be formulation Y which again costs Sunoco less at the given batch time. Thus the formulations, all of which do achieve 100 octane rating because that is what the customer is purchasing, may have different blending agents or ratios for a given batch.
Thus, I do not think Chip realistically can answer this question.
Citgo and Chevron are completely different companies and most east coast gas is different from west coast gas regardless of the maker.
Chip
Gentlemen,
A lot of members confuse Octane Ratings with energy content. They are two different things. Ethanol has an energy content of about 65% that of gasoline. But Ethanol has an Octane rating of about 120. Octane is "resistance to detonation", nothing more. I sell E-85 that cab drivers are forced by law to use if they service the Phoenix airport. The drivers all hate it as it only costs about 15% less than gas and they get 30% less mileage. I need to use all stainless steel equipment in my E-85 tank and pumps as it is very corrosive. It also wicks up moisture like a sponge. Storing a car with ethanol in the gas is much harder on it than storing a car with 100% gas. Ethanol blended fuels go stale quicker and both corrode and turn to varnish faster. I hate ethanol and don't think it should be blended into any gasoline. It's use is purely political and it wouldn't exist without mandates.
The cheapest and easiest way to boost octane in gasoline is with tetra-ethyl lead. 100 octane AvGas is standard 93 octane unleaded with a very small amount of tetra-ethyl lead added. That small amount is needed to lubricate the valves in air cooled aviation engines that also require the higher octane. The components used to boost octane to 100 in unleaded race gas are much more expensive and that fuel is only suitable in engines with valves that don't require lead.
Ethanol sucks and I would avoid it completely if it was possible. In most areas it is in all gasoline now however.
Chip
A lot of members confuse Octane Ratings with energy content. They are two different things. Ethanol has an energy content of about 65% that of gasoline. But Ethanol has an Octane rating of about 120. Octane is "resistance to detonation", nothing more. I sell E-85 that cab drivers are forced by law to use if they service the Phoenix airport. The drivers all hate it as it only costs about 15% less than gas and they get 30% less mileage. I need to use all stainless steel equipment in my E-85 tank and pumps as it is very corrosive. It also wicks up moisture like a sponge. Storing a car with ethanol in the gas is much harder on it than storing a car with 100% gas. Ethanol blended fuels go stale quicker and both corrode and turn to varnish faster. I hate ethanol and don't think it should be blended into any gasoline. It's use is purely political and it wouldn't exist without mandates.
The cheapest and easiest way to boost octane in gasoline is with tetra-ethyl lead. 100 octane AvGas is standard 93 octane unleaded with a very small amount of tetra-ethyl lead added. That small amount is needed to lubricate the valves in air cooled aviation engines that also require the higher octane. The components used to boost octane to 100 in unleaded race gas are much more expensive and that fuel is only suitable in engines with valves that don't require lead.
Ethanol sucks and I would avoid it completely if it was possible. In most areas it is in all gasoline now however.
Chip
AJB
GT
2112 YES - CITGO is the Venezuela State owned, America Loving, Hugo Chavez oil Company. I have boycotted them for many years.
ajb (andy)
ajb (andy)
