Gas for classic cars?

Hi Guys,

I got a 1967 Ford Galaxie 500XL a couple years ago, and I’m not sure what gas to put in it. I don’t drive it often, so the question hasn’t come up much yet. I usually do premium (91 octane around here), and put in some octane booster once upon recommendation from my dad (from whom I got the car).

I figured I could just google for this and easily find out, but the internets haven’t been too helpful so far. I’d like to get a few opinions on this before I screw something up.

The engine was rebuilt before I bought it, so not everything in there is 40 years old…

Thanks for the help!

I had one of these cars! Got the 390 CID 4bbl? Great car!

All I can tell you is, avoid putting in any gasoline that contains any ethanol. When Minnesota mandated E10 as the main motor fuel in 97, it raised all kinds of hell with the fuel system in this car. I went through two fuel pumps and rebuilt the carburator twice in six months because the ethanol destroyed the rubber diaphram in the pump and the rubber components in the carburator. You have to remember, this fuel system was never designed to handle the corrosive nature of ethanol. And this is one of the reasons why Minnesota allows some gas stations to sell gasoline with no ethanol.


Yup the 390. :slight_smile:

I’m not sure if I can even find anywhere around here that doesn’t sell only E10. I’ll have to start paying more attention. I was actually more worried about the octane rating.

Here’s a link to the Minnesota Street Rod Association. Here they provide a list of gas stations that sell non-oxygenated (no ethanol) gasoline. See if there’s a street/hot rod club in your area that might be able to provide you with information about obtaining gasoline for older fuel systems.


Good idea. I’ll see what I can find out.

Thanks for the help!

I’ve always recommended that cars built before 1970 use a lead substitute additive in the gasoline. The main purpose being to protect soft valve seats that were prevalent before the early 70’s. However, since the engine has been rebuilt I don’t know if this is really something to be concerned about anymore.

If you’ve had an older engine rebuilt within the last ten years, most likely hardened valves and valve seats were installed. If so, a lead substitute isn’t required.


There are modified engines that do well on today’s gasoline. They have lower compression pistons.

When I had my Chevelle, I always filled it up with 93 octane. There is 1 station around here that sells 110 octane, but it’s cost is up there with diesel, and I doubt it would have done any good. The engine was a 2bbl 283 v8