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will a 1978 gen 1 Brat run off of unleaded gas


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I'm about to buy a 78 brat and i'm wondering if the car is capable to run off of Unleaded gas with out damaging the internal components of the engine. 

 

 

will i need to put a lead additive in my brats fuel system 

 

If not what needs to be done to my stock carb to handle the higher burn temp of unleaded gas? 

 

Also most gas has about 10% ethanol in the gas now a days,  so will that do any harm to the engines?

 

 what should i know in general about the old EA71 motor to insure that i can prevent any damages due to my lack of knowledge on  30+ year old carbed  engines. 

 

For shits and giggles do any of the later engine models fit in the 78s engine bay and are adaptable to the stock transmission 

 

 

 

 

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Unleaded shouldn't be a problem, the compression ratio is low and the valve seats are hardened. 10% Ethanol gas is probably not an issue if you keep on top of checking your fuel hoses for any swelling/leaking. It may eat the carb float and/or accelerator pump eventually, but a newer rebuilt kit might have compatible rubber/plastic. I'd recommend you go through the carb anyway, its not hard to rebuild and would likely be gunked up if the car had sat for an extended period of time with fuel in it.

 

The 'top-mount' starter EA71 engines would need the bellhousing of a later "side-mount" starter to match with a later transmission, giving you low range and 5 speeds. Later engines (EA81/EA82) would require custom crossmembers and other such magic to make fit. At that point, maybe putting on a Weber carb would get you some power.

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Unleaded fuel is not a problem at all, it is all I have ever used in any of my old Subarus but (in Australia at least) Subaru does not recommend the use of ethanol in these models.

 

Is it difficult to get unleaded without ethanol in the US? Not worth it in my opinion, less performance and more fuel used...

Edited by Leeroy
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Thats all we are fed these days is unleaded ethanol soaked gas.

the time of year and elevation depends on how much they add.

When i had the Hitachi it was more troublesome because of the plunger style accelerator pump and all the o-rings.

Kit after kit the fuel would eventually swell it up and turn it to mush after a year. that goes for the carter i had on my 62 chevy too.

The weber has a diafragm accelerator pump mounted on the side and can be changed without removing or opening up the carb. I have used the cheap holley ones they sell at auto zone and re- drilled the holes and they work fine. when they go bad you will smell and see a fuel leak and that  keeps me on top of it.

I know there are alot of die hard hi-crotchy carb fans out there but they now are too touchy with the crap gas we are forced to buy these days.

My uncle said that back in his day a flat head v8 ford could get 20-24 mph on the real stuff they used.

We are a captive audience to oil companies so the more efficient cars get, the more ethanol they add to get their pennies worth.

I just pray the day dont come where we can no longer run our carbs on the new fuel mixtures

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I'm about to buy a 78 brat and i'm wondering if the car is capable to run off of Unleaded gas with out damaging the internal components of the engine. 

 

 

will i need to put a lead additive in my brats fuel system 

 

If not what needs to be done to my stock carb to handle the higher burn temp of unleaded gas? 

 

Also most gas has about 10% ethanol in the gas now a days,  so will that do any harm to the engines?

 

 what should i know in general about the old EA71 motor to insure that i can prevent any damages due to my lack of knowledge on  30+ year old carbed  engines. 

 

For shits and giggles do any of the later engine models fit in the 78s engine bay and are adaptable to the stock transmission 

I have switched both of mine to ea81 and dual range trans. Fairly easy to do with small modifications. the ea71 setup in my opinion is fine for trail cruising  or street driving an not much difference in power is noted. but to get up the steep hills and rough country you need the low gear because  that engine will bog down fairly easy.

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