What kind of gas are you using?, modern 91/93 with ethanol or non-ethanol with octane booster Options

[boxster914]

I've just been given two conflicting suggestions:

Run non-ethanol 89 octane gas and use a lead substitute (instead o' lead)

or

just use modern 91/93 octane gas that contains ethanol.

I had been using non-ethanol gas in my 72 Beetle and then switched to modern 91/93 gas with ethanol and it seemed to develop a hesitation on acceleration.

I just got a 71 914 and am interested to know what you all are using so I can decide which gas to use in it.

[ndfrigi]

check this site.

https://marcnelsonoil.com/the-pros-and-cons...on-ethanol-gas/

[BPic]

If you want Ethanol free gas check out this site. Click maps and enter your state.

https://www.pure-gas.org/

[jfort]

Had a long talk with Richard Parr, the maker of PMO carbs, on this issue recently. My choices are 93 octane with ethanol or 90 octane with no ethanol. He suggests the latter with a supplement. I use Turbo 108 Octane Boost. All seems well with a 2.7 six with 10.8 compression twin spark.

[bretth]

My limited understanding is that higher octane fuel does not burn as easily as lower octane. So putting high octane in a low compression motor is basically useless. Don't know how common low octane ethanol free gas is though.

[gfg3]

I've been using 87 octane ethanol free in my '75 2.0 for 5 years. No additives. Continues to run great. As an aside, I use 93 octane ethanol free in my '61 Ford big block. Again, no additives. Running great for years.

[73-914]

only Stewart's 91 ethanol-free

[Sprout]

I've been using 87 octane ethanol free in my '75 2.0 for 5 years. No additives. Continues to run great. As an aside, I use 93 octane ethanol free in my '61 Ford big block. Again, no additives. Running great for years.

(IMG:style_emoticons/default/agree.gif) same 87 octane ethanol free in my 73 1.7 FI, no additives. Been using it in my 69 Bug many years as well.

[flat4guy]

Chevron Supreme

[mark04usa]

Chevron Supreme

(IMG:style_emoticons/default/agree.gif) I've used same for years...my early 1.7 wants high octane to avoid pre-ignition and vapor lock... problems solved with this fuel.

[VegasRacer]

Chevron Supreme

(IMG:style_emoticons/default/agree.gif) I've used same for years...

(IMG:style_emoticons/default/agree.gif)

If I'm road tripping and can't find it, then Texaco or Shell. (IMG:style_emoticons/default/driving.gif)



*(my Mazda RX7 Race Car ran best on the shittiest gas you could find. Some guys would go down to TJ and fill up 55 gal. drums of Pemex.) (IMG:style_emoticons/default/bandit.gif)

[Racer]

Comes down to what's available. Some states don't allow non-ethanol fuels to be put in cars. others have no issue with it.

These cars were built to run on leaded regular (which of course did not have ethanol). Good luck finding that (IMG:style_emoticons/default/wink.gif)

Most cars get buy with any 87-93 octane fuel, ethanol or not. If you've advanced your timing trying to squeek out the last few hp, running 91 or higher could help with some predetonation.

If you are using an ethanol fuel in a car that sits awhile, run some kind of Stabil/Heet/Water evaporator to help keep lines and injectors/carbs cleaner.. not spotless, but cleaner.

Feel free to add a lead additive if you are worried about valvetrain wear.

Asking what fuel to use is like asking what oil to use. Everyone will tell you something to conflict with the last opinion!

[bbrock]

Comes down to what's available. Some states don't allow non-ethanol fuels to be put in cars. others have no issue with it.

These cars were built to run on leaded regular (which of course did not have ethanol). Good luck finding that (IMG:style_emoticons/default/wink.gif)

Most cars get buy with any 87-93 octane fuel, ethanol or not. If you've advanced your timing trying to squeek out the last few hp, running 91 or higher could help with some predetonation.

If you are using an ethanol fuel in a car that sits awhile, run some kind of Stabil/Heet/Water evaporator to help keep lines and injectors/carbs cleaner.. not spotless, but cleaner.

Feel free to add a lead additive if you are worried about valvetrain wear.

Asking what fuel to use is like asking what oil to use. Everyone will tell you something to conflict with the last opinion!

(IMG:style_emoticons/default/agree.gif) except I'm not sure what would be gained with a lead additive since our cars have hardened valve seats. (IMG:style_emoticons/default/confused24.gif)

There is no advantage to running higher octane than needed unless you are trying to lose weight in your wallet. All stock 914 engines should run fine on regular octane unless you've tweaked them from stock specs.

I haven't driven my 914 since the days of leaded but hopefully she'll be mobile by this spring. I'll fill with ethanol free gas most of the time but won't hesitate to fill with ethanol blend on long trips when I know the tank will be used before storing the car for any length of time. If I do have to park the car for any length of time with ethanol blend in the tank, I'll use a stabilizer additive.

[oakdalecurtis]

One other thought not mentioned. The lower the octane you use, the COOLER the engine will run. You should run the lowest octane possible as long as your engine doesn't knock. This means that primarily only higher compression altered engines will require above 87 octane.
I've been running California's 15% ethanol blend 87 octane gas for 20 years in my stock smogged 76 2.0 and it hasn't missed a beat.
(IMG:style_emoticons/default/beerchug.gif)

[Gint]

Oh boy. I've seen this subject come up over and over again through the years.

Comes down to what's available. Some states don't allow non-ethanol fuels to be put in cars. others have no issue with it.

These cars were built to run on leaded regular (which of course did not have ethanol). Good luck finding that (IMG:style_emoticons/default/wink.gif)

Most cars get buy with any 87-93 octane fuel, ethanol or not. If you've advanced your timing trying to squeek out the last few hp, running 91 or higher could help with some predetonation.

If you are using an ethanol fuel in a car that sits awhile, run some kind of Stabil/Heet/Water evaporator to help keep lines and injectors/carbs cleaner.. not spotless, but cleaner.

Feel free to add a lead additive if you are worried about valvetrain wear.

Asking what fuel to use is like asking what oil to use. Everyone will tell you something to conflict with the last opinion!

(IMG:style_emoticons/default/agree.gif) except I'm not sure what would be gained with a lead additive since our cars have hardened valve seats. (IMG:style_emoticons/default/confused24.gif)

There is no advantage to running higher octane than needed unless you are trying to lose weight in your wallet. All stock 914 engines should run fine on regular octane unless you've tweaked them from stock specs.

I haven't driven my 914 since the days of leaded but hopefully she'll be mobile by this spring. I'll fill with ethanol free gas most of the time but won't hesitate to fill with ethanol blend on long trips when I know the tank will be used before storing the car for any length of time. If I do have to park the car for any length of time with ethanol blend in the tank, I'll use a stabilizer additive.

(IMG:style_emoticons/default/agree.gif)

I have an Original Customs 2056, carb'd. I run whatever regular I find at the pump, occasionally I'll try a mid-grade. Doesn't make any difference. Never had any problems. No need for lead additive in my opinion. Runs great. If I know it's going to sit for a while (like at the height of the pandemic and quarantine etc...), I definitely put Stabil in the tank. Cheap peace of mind.

[bbrock]

check this site.

https://marcnelsonoil.com/the-pros-and-cons...on-ethanol-gas/

Nice article but it understates the ecological train wreck ethanol fuels have caused in the Midwest.

[horizontally-opposed]

My mechanics know their stuff, and both recommend running 91 from Chevron or 76. Ethanol is tough to avoid here in CA.

I can get higher octane—and even leaded race gas—by driving over to Sears Point, but I very rarely do so. I tend to forget which octane I should go for, and whether it would be helpful or harmful with an engine built and tuned to run on our crappy 91-octane gas. Will say it made 169.9 rwhp (so, 190-200 hp at the flywheel?) from 2.2 liters on CA 91 and runs beautifully throughout the rev range.

I'd be very curious to hear what someone like Jake Raby or others here have to say about the occasional tank of leaded race gas, and if there are any benefits. I suspect any octane bump would be wasted?

[BENBRO02]

I use regular (87) from any gas station with ethanol. 15,000 miles in 2 years with good performance and no problems. I’m much pickier about my oil.

[Olympic 914]

2056 with 8.6 comp I usually run the mid-grade, 89 10% ethanol.

Occasionally I will put in the 93 from Sam's Club because it is cheaper than the 89 elsewhere.

Runs just fine.

[DRPHIL914]

i usually run the NO ethanol 87or89 on my stock 2.0/4 motor. i only get the 10% if i know i am burning thru a whole tank, and since the car may sit for a few weeks with out driving i will put stabil in a full tank. we have no problem getting non-ethanol gas but it does cost about the same as 93 octane premium.
remember for the low compression cars 1.7,1.8, 2.0 stock motors 87 is what factory tuned the car for. i set my timing with this in the tank, if you run 93 instead of 87, it will effect you even if you think i’m your seat of the pants experience and feeling it’s running “just fine” . and for sure if you just got the car change out all your fuel lines for the ethanol rated ones. ethanol even just 10% will attract moisture if it’s sitting in that tank and we live in a high humidity region, so i try not to use it. same reason you should never run it in you 2stroke or 4 stroke lawn equipment!