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Discussion Starter #1
Can anyone tell me what gas I should be running in my 78 mustang, original 2.3.
 

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I'm not sure, but ethanol might degrade some of your rubber parts in the fuel system. Most of which can be upgraded with modern fuel hose if it does.
 

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Discussion Starter #4
Anything in the carburetor that can be ruined? Mines not getting fuel but the fuel pump is putting out and the lines are not plugged and it’s coming through the filter, we have spark so not sure what is going on.
 

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If you have used ethanol gas and let the car sit for a couple of months you may need to disassemble the carb and clean it.
Will it run or sputter with a little gas poured down the carb?
 

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I always use non-ethanol fuel in everything but my wife's new vehicle and my old diesel truck !
 
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I personally use non ethanol (mostly 98 octane) fuel with lead additive. Im a newby to this so dunno if that is good or bad
 

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Discussion Starter #8
It will not start even pouring gas down the carb but it has never sat longer than 2 weeks since I bought it in August.
 

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It will not start even pouring gas down the carb but it has never sat longer than 2 weeks since I bought it in August.
I hope you're using the word 'pouring' in the figurative sense, otherwise, it's now flooded. A few small trickles should
do it.
 

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Discussion Starter #10
No its not flooded. lol Yes it was a trickle. Gonna try cleaning the carb today
 

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Can anyone tell me what gas I should be running in my 78 mustang, original 2.3.
Well U could ask Google that ?
U didn't mention if U were having a running issue, or if U were just asking.
Or, U could try "the trial & error" approach, by using a mid grade like 91 octane rated.
If the car runs OK, try going to 89. If it still runs OK, try 87. If it runs OK on 87, then U don't need any better. If you notice it running poorly or seems to lack power, go back to 89 octane and so-forth.
The car will tell U what it needs, assuming all else is up to par, like tunning, etc.
Once U find the octane it likes, going to a higher octane isn't necessary and is a waste of $.
Good luck! 😊
Anything in the carburetor that can be ruined? Mines not getting fuel but the fuel pump is putting out and the lines are not plugged and it’s coming through the filter, we have spark so not sure what is going on.
If U've got gas @ the filter & the carb is next and no gas, then u know the carb is clogged.
Time for a rebuild!
But first check the screen where the fuel line attaches to the carb.
 

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See if you floats are stuck closed


A few light raps with a hammer and block of wood at the inlet may dislodge it.

If not you'll have to open the air horn and see whats going on.
 
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The compression in that engine is so low you could almost run diesel and be OK.

Seriously, whatever is at your local filling station is fine. If you have a convenient source of100% gasoline, sure, run that. If not, you'll be fine with "up to 10% ethanol". Whatever problem you're having right now has nothing to do with the gasoline.
 

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Discussion Starter #16
The compression in that engine is so low you could almost run diesel and be OK.

Seriously, whatever is at your local filling station is fine. If you have a convenient source of100% gasoline, sure, run that. If not, you'll be fine with "up to 10% ethanol". Whatever problem you're having right now has nothing to do with the gasoline.
Thank you.
 

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Yup 100%.
Do you have spark or strong spark? I’ve had a car with starting issues and spark and discovered that it was still spark related. Bad coil or points is often the culprit. I don’t know much about the late 70s motors... so they still is points or were they upgraded to some fancy duraspark setup?

Rob
 
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