Gasoline Recommendation

[Robert Street]

I have a 61 SS Impala and a 62 SS Impala both with 409's and original AFB carbs.  Also have a 61 Impala with a dual carb 348 but is a lower compression engine.  Since these cars are not driven but shown I have always used racing gas and great results. But in my area racing gas is becoming a hassle to get.  I have been using ethanol free in my small engines and boat engines with great results.  Any recommendations about switching to mid grade (91) in these engines.  LL100 avgas is also an option for me.

Robert 

[C Carl]

If 91 is mid grade in your area, what is the highest octane available ? In any case, ethanol free gasoline of whatever highest octane is fine to use in any car which is driven lightly. Octane requirements go up as manifold pressure goes up. If you get on those cars occasionally, fuel accordingly. I gave my 10:1 Cadillacs a dose of 100, or 110 from time to time, and hammered them. They thanked me.  -   Carl 

[Frank DuVal]

93 is the highest in this area, VA, MD, DE, at regular filling stations. What's a filling station you ask?😁

 

Typically 87, 89 and 92/3 at most stations. 91 non-ethanol is at a few stations, just not around DC. Hard to find non-ethanol in areas here that have emissions testing.

 

If you cannot hear ping getting on and off the trailer, you will be fine with low octane non-ethanol fuel.😉

 

 

[John_S_in_Penna]

42 minutes ago, Frank DuVal said:

What's a filling station you ask?

 

Well, they're just about all FILLING stations these days.

Almost none are SERVICE stations!  

[real61ss]

We are lucky in central Virginia, we have access to 89 and 93 oct. Non ethanol gas plus 110 oct. tacing gas. Actually we have a speed shop near me that has various octane racing gas. You could probably purchase 10 to 15 gal and it would be enough for the two show cars for a season. If you purchased it in those plastic racing jugs it shouldnt go bad

[padgett]

Agree, I use 93 plus CD-2 and Sta-Bil in the Judge. Mercs I mix 89 and 93 to get 91.

 

[JACK M]

I deal in race gas. Most of the race gas has lead in it.

It is for OFF ROAD only.

OK, I cheat some on that. It works great for storage as it is quite stable. Also good for a treat once in awhile on these oldies.

But BEWARE, if your car has a catalytic converter the leaded  gas (or lead substitutes) will ruin it.

[Frank DuVal]

On 8/13/2019 at 11:35 AM, padgett said:

Mercs I mix 89 and 93 to get 91.

 

Visit a blender pump and it does it for you. Once in a while you see a blender pump on steroids...😉

 

Most every new station just has 87 and 93 tanks in the ground around here. Midgrade comes form blending at a certain ratio.

Edited August 15, 2019 by Frank DuVal
Pictures added (see edit history)

[Robert Street]

Thanks for the suggestions guys.  I am going to try to get to Richmond to Tommy Nolen's with several containers as he is correct 10 gallons or so will last a show season. Plus I would get to visit his rotating inventory. Plan B is LL 100 avgas which is fairly easily purchased around here.  I am concerned with driving a few miles to a station that does sell Non-ethanol because of the concern that the tanker had some ethanol in it.  Also I am concerned with non-ethanol shelf life vs av gas or Sunoco racing gas.

As far as concerns about leaded fuel inspections my cars are not tagged thus not driven on the street.  Yes, I have experienced plug fouling but have cured that by using AC 46S series plugs and that problem is gone.  The only time the front carb is ever fully opened or the secondaries in the rear carb opened is for the small spritz of starting fluid need to fire them up.

Thanks

Robert

[Frank DuVal]

On 8/13/2019 at 7:22 AM, real61ss said:

If you purchased it in those plastic racing jugs it shouldnt go bad

 

??? What does plastic have to do with keeping gas from going bad?

 

1 hour ago, Robert Street said:

 Yes, I have experienced plug fouling

 

This is just from not driving them. Cars were built to be driven. Operate them in a different manner and then you need to do things not recommended by GM, like running 46S plugs. These are way too hot for street use in these engines, but works for trailer queens.

 

I would be using gasoline (capfull only)) and not starting fluid. These high compression engines knock a lot when they get a whiff of starting fluid. Have you thought about adding an electric pump to fill the carburetor  only, not to run the engine? Much easier on the engine internal parts. I know, hard to hide switch for AACA judging....😯

[real61ss]

10 hours ago, Frank DuVal said:

 

??? What does plastic have to do with keeping gas from going bad?

 

 

This is just from not driving them. Cars were built to be driven. Operate them in a different manner and then you need to do things not recommended by GM, like running 46S plugs. These are way too hot for street use in these engines, but works for trailer queens.

 

I would be using gasoline (capfull only)) and not starting fluid. These high compression engines knock a lot when they get a whiff of starting fluid. Have you thought about adding an electric pump to fill the carburetor  only, not to run the engine? Much easier on the engine internal parts. I know, hard to hide switch for AACA judging....😯

I don't think the fact that the jug is plastic has anything to do with it but the jugs that they sell the racing fuel in appear to be much more air tight although I guess the have to have some ventilation . I might be totaly wrong, they just appear to be much better than these a much better jug

[Frank DuVal]

I agree that they are good jugs! Plus they have that nice long spout to get fuel into caps behind fuel doors on many cars and trucks. 

 

Nothing more irritating than currently sold gasoline containers at stores.😡 I buy the yellow vents on  line and add them while modifying the open/close mechanism too. 

[Marty Roth]

I use CD-2,

plus Star-Tron,

plus Marvel Mystery Oil-

 

Probably overkill, but a few extra bucks spent since we DO drive ours cross-country is peace of mind