Ethanol free gas
November 9th, 2022, 12:59 PM
#1
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Ethanol free gas
I have been battling with lean running conditions based on my plug readings. Many on the site suggested my stock calibrated Quadrajet was likely not jetted rich enough for ethanol gas. I just filled the tank with ethanol free gas and there is a noticable increase in power. The tip in response has always been good, but what's really noticable is the power after initial throttle. The gain feels like the same increase I got on my 2015 mustang gt after installing the cold air intake which K&N advertised as 20 hp. Kind of spendy for the gas, so I will probably re-jet my carb.
November 9th, 2022, 05:31 PM
#4
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The reason that the carb should be re-jetted a step or two richer, is that ethanol has less heat content per gallon than pure gasoline.
These carbs were originally jetted for pure gasoline.
If you mix 10 percent ethanol with gasoline the mixture has less heat content than pure gasoline.
You must jet the carb slightly richer to make up for the loss of heat content to make the most power.
Otherwise, the fuel mixture will be too lean.
These carbs were originally jetted for pure gasoline.
If you mix 10 percent ethanol with gasoline the mixture has less heat content than pure gasoline.
You must jet the carb slightly richer to make up for the loss of heat content to make the most power.
Otherwise, the fuel mixture will be too lean.
Last edited by Charlie Jones; November 9th, 2022 at 08:12 PM.
November 9th, 2022, 06:57 PM
#5
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November 9th, 2022, 07:00 PM
#6
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The reason that the carb should be re-jetted a step or two, is that ethanol has less heat content per gallon than pure gasoline.
These carbs were originally jetted for pure gasoline.
If you mix 10 percent ethanol with gasoline the mixture has less heat content than pure gasoline.
You must jet the carb slightly richer to make up for the loss of heat content to make the most power.
Otherwise, the fuel mixture will be too lean.
These carbs were originally jetted for pure gasoline.
If you mix 10 percent ethanol with gasoline the mixture has less heat content than pure gasoline.
You must jet the carb slightly richer to make up for the loss of heat content to make the most power.
Otherwise, the fuel mixture will be too lean.
November 9th, 2022, 08:04 PM
#9
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It is pretty well proven that straight gasoline will deliver better fuel economy than ethanol laced fuel.
Whether the increased fuel economy makes up for the higher price, depends on the difference in price.
Whether the increased fuel economy makes up for the higher price, depends on the difference in price.
November 9th, 2022, 09:14 PM
#10
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It's aboUt 20% more. $6.40/gal vs $5.40/gal. In WA State. there are other advantages from what I have read. Ethanol and running lean is not really good for your engine. And the performance definitely puts a smile on my face. There is a 0.35 mile stretch on a back country straight away I use as a testing ground. I can usually get the car up to about 107 to 110 when it's running right. I buried the speedometer on the same length of road tonight.
November 10th, 2022, 11:22 AM
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November 10th, 2022, 11:28 AM
#13
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Too rich to run E 10 at all.
That means that your travels would be limited to areas where E 85 was available.
November 10th, 2022, 11:30 AM
#14
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Location: Williamstown, WV
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Few years back, my original fuel pump went out about same time I noticed gas cap seal turned gummy. I blame ethanol.
RV90 ethanol free is what I run in lawn tractors and before my 68 goes into hibernation. $1.50 more than 92 unleaded.
Mader
omy442
RV90 ethanol free is what I run in lawn tractors and before my 68 goes into hibernation. $1.50 more than 92 unleaded.
Mader
omy442
November 11th, 2022, 07:31 AM
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November 11th, 2022, 08:56 AM
#19
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I do, I have a whole lot less in my car compared to a new one, it's just as reliable and more fun. We have both ethanol and ethanol free 91 here locally, I use both. I miss the 93 ethanol (not available locally) that the car has run on for the last 12 years. I had to drop the timing a bit to run the 91.
November 13th, 2022, 04:10 AM
#22
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Living in South Carolina now, I'm now able to run Ethanol Free gas in all the old cars now all the time, from my 1996 Cutlass Supreme on down. I noticed an immediate difference in smoothness, especially my 3.4 1994 Cutlass. I specifically had the dualjet in the blue 79 Calais rebuilt to run on ethanol free only, big improvement.
The only drawback is the octane is 87. Not much more is needed around here since the stations selling ethanol free gas are really catering to the boating crowd of which there is alot of here. Occasionally I'll throw in some Lucas Octane Booster in the 79 Hurst Olds or the 94 Cutlass. The other cars are such low horsepower/low compression cars that using Octane Booster is not worth it.
The only drawback is the octane is 87. Not much more is needed around here since the stations selling ethanol free gas are really catering to the boating crowd of which there is alot of here. Occasionally I'll throw in some Lucas Octane Booster in the 79 Hurst Olds or the 94 Cutlass. The other cars are such low horsepower/low compression cars that using Octane Booster is not worth it.
Last edited by BlueCalais79; November 13th, 2022 at 04:19 AM.
November 13th, 2022, 06:52 AM
#23
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Here 87 is 10% ethanol, 89 is about half as much, mixed Premium and Regular at the pumps. All our Premium is ethanol free, most is 91, finding 93 is almost impossible here. I use 91 only in my boat, flush the pump lines into the Challenger or Dakota. Do the same for anything the sits for months my pressure washer for example, along with STP additive. I have been using on 91 in my 70S which is $6.88 CAD per US gallon currently, it was over the $7 mark this Summer!
November 13th, 2022, 10:01 AM
#25
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Apparently not all ethanol free gas is created equal. The first tank I filled about 18 gallons with 92 octane ethanol free from Chevron, although the pump said it was not a Chevron product. After about 1/2 a tank, I topped it off with 92 octane ethanol free at Safeway thinking gas from the same blue pump was likely from the same company as Chevron, but the car did not perform as well and there was considerable pinging at higher RPM. There was no pinging from the gas I got at Chevron. I typically only buy my gas from top tier stations and will continue to do so whether it be ethanol free or not.
November 13th, 2022, 12:15 PM
#27
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