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87 octane sure doesn't do my 69' any good. It's in getting it's original carburetor rebuilt right now and the mechanic said the older cars were not made for 87 and just don't do well over time. :nerd:
thread question...I ran 87 in 3230 for years in daily commute no issues....then I modified it...no more commute vehicle!!!

Vicki,
Huge issues with todays gas and older vehicles to be mindful of...
I still run 3 carb'ed vehicles...issues I protect against:

todays gasohol reeks havoc on older cars, alcohol is exceedingly caustic
* change all your fuel lines to modern alcohol resistant hoses. Older rubber hoses WILL corrode/disintegrate from the alcohol, creating a fire hazard...not what you want in a classic vehicle!!!
* because of the rubber issue, an item typically never considered/overlooked is the mechanical fuel pump....which has a fuel facing rubber diaphragm...corrodes...fails...pouring gas into your engine diluting the oil...there goes your engine
because of this risk, I have eliminated the mechanical fuel pump in all my vehicles and installed an electric pump. However, electric pumps aren't as reliable as old mechanicals, so, I always keep a mech pump
in the vehicle in case I ever have issues, and can do a quick temp swap out. Be sure to protect your vehicle with oil pressure cut offs or other style safety switches. Also, given variable to high pressure potential of electric pumps, I also installed a fuel pressure limiter (set to 4-5 lbs psi) to protect the carb from being force fed (high pressure will cause issues with your float and inlet needle valve)
* another issue answered with the electric pump is vapor lock. The mechanical fuel pump draws fuel from the tank, the low pressure created in the line exacerbates vapor lock with todays fuel given the fuel will more readily boil than non-alcohol fuels...alcohol has lower boiling point. If your old car experiences more vapor lock issues in hot conditions than it did in the past, guaranteed this is your problem in todays world. The electric pump however pressurizes the fuel line from the tank to the engine, and virtually eliminates all vapor lock issues in carb engines, even in worst case hot conditions, given it significantly raises the boiling point.
* alcohol, being caustic, also causes havoc within the carb, deteriorating fragile components, floats, excellerator pumps, etc etc.

Using Stabil can mitigate against corrosion issues, but will NOT completely eliminate the risks, nor will it do anything about the vapor lock issue.
I only use my vehicles for occasional recreational use, and even with the above protections, I almost always use non-ethanol fuel...its worth the extra $$ for the piece of mind.

The only other issue with older vehicles are generational in metallurgy, eg, engines built in the leaded gas era. The biggest issue were the valve seats, which were too soft to endure non leaded gas for long, and can eventually cause valve train issues. Most cars by early 70's started hardening seats in preparation for the coming non-lead days, but...not sure about 69. So, if your heads have never been rebuilt, that may eventually drive poor running conditions in your engine with burned out valve seats. A Vacuum gauge...if you can actually find anyone nowadays who even knows how to interpret one, can quickly/easily determine burned seats.
 

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In my area REC 90 (no ethanol) fuel is available at multiple stations. I have a Premium tune and am torn between keeping the tune or using REC 90.

Thoughts?
 

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PhotoRick, First, this is just my opinion based upon not facts whatsoever.

If the car is driven enough, I would just stick with the Premium with it's 10% booze. If the car sits a lot, then go with the "no ethanol".

The biggest problem with ethanol is it's reaction with moisture. Ethanol will absorb the moisture from the air and if the car sits, the ethanol (mixed with water) will separate resulting in all kinds of issues. If you drive the car fairly regularly, that will allow the fuel to stay mixed and you will use it before the moisture becomes a problem. Older cars (back in the days of a carburetor), also have other issues with Ethanol since Ethanol does not "play" very good with rubber. It likes to eat it. The 2001 have newer fuel lines and parts that can tolerate up to 10% ethanol. DON"T GO HIGHER WITHOUT MODIFYING THE CAR TO HANDLE IT.

What I have found is that some vehicle (not all) get much better fuel mileage with NON-ETHANOL (such as my old Ranger). In most cases, the improvement in fuel mileage totally offset the additional cost.

Just my 2cent worth (worth less than a penny today).
 

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Mine sits a lot and I have been having trouble with the fuel. I added some additives to it that have helped. Right now I am trying to burn up the old fuel. Then I am going to put some ethanol free 92 octane gas in it and see how it does on that. My car is tuned, so I will probably bump the timing down 1 degree and see how it runs. It will be fine as long as there is no detonation.
 
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