Unleaded gas in 1983 Chevy 454?

[Alexarae]

Hello Everyone...can we run unleaded fuel in a 1983 chevy 454? If so what year did Chevy convert their 454 engine to unleaded use for chassis for Winnebago's...we have a 1983 Brave on a 1 ton Chevy chassis. Thank you

[circleD]

Unleaded is the only thing you can really run it on. Yes it was made to run on unleaded.

[MotorPro]

Yes an 83 engine will use unleaded gas

[Alexarae]

Thank you very much   Merry Christmas to all ☆☆

[Froggy1936]

Unleaded fuel came into being in 1975 Anything made after that date will use it !Frank

[EldoradoBill]

All General Motors engines from 1972 on up were designed to run on unleaded. Says so in the respective owners manuals. It's the ethanol they mix some of the fuels with today that may play havoc if it sits around long enough.


Bill

[DRMousseau]

Yup,... Bill's got it! Most all domestic manufactures were preparing for unleaded use before it was exclusive. It was clear that it was coming, and in the crossover years, using leaded fuels in those designed for unleaded was a bigger problem.

But no one foresaw the extensive use of ethanol that would soon come. It had only seasonally or occasionally been added to the vehicle fuel tank as needed, to prevent fuel-line freeze-up and to rid the tank of accumulated water due to humidity and condensation as fuel tanks were then openly ventilated. My old Onan has a water-separator-sediment bowl and filter assembly that at one time had to often be drained of water accumulation... and hardly at all now with added ethanol fuels. Many gas stations were "blacklisted" if customers had found excessive water in their tank to poor care and maintenance of the stations bulk storage,... pretty much unheard of today.

But most, if not all, early engine and fuel systems were not designed to resist the effects of ethanol as commonly used today. THIS should be of greater concern to those of us who drive classics, then that of unleaded fuel.

[Rickf1985]

There is a misconception between the alcohol used back then in dry gas and today in the fuel. What was used back then was methanol and what is used in the gas now is ethanol. Two totally different compounds.

[DRMousseau]

Yes they're very different,.. methanol is miscible (sp?) in water and ethanol is soluble in water. And yes, methanol is slightly more corrosive. Both will cause some "plastics" to craze and/or become stiff and brittle over time,... most notable were early plastic and rubber compounds. Not as serious an issue as the other effects of alcohol when used as a gas additive in early engines. Once prohibited for aircraft, it may still be,... and still not recommended for most marine engines.

Methanol was typically added to ethanol and was labeled denatured alcohol to prevent consumption, and packaged for use as a solvent, "dry gas", stove fuel, antifreeze and such, where ethanol's properties were much more desired over that of methanol. But most times, ya never knew WHAT the denaturing additive was, and it's best jus to use for the intended labeled purpose.

If ethanol is not denatured,... it's usually labeled as Corn Liquor, Vodka or Rum!!! Lol!!!

And that reminds me,... I better go check and see it the bubblin' has stopped yet!!!

[circleD]

Well Alexarea, does this answer your question?  . You will find out that there are people on this forum that have insight and those with knowledge. Both types are helpful. And if we don't know we can guide you into the right direction? 

[Alexarae]

First I'd like to say so sorry for taking so long to respond to all the fantastic help. We haven't been on the computer in a few weeks as Alexarae has had some medical issues (she's almost good as new now !!!) and with the holidays and the business we have been a lil' sidetracked to say the least. All of the people here are the GREATEST !!!! We are so glad we found this site. We are amazed at all the knowledge this group has and is helping us beyond expression. THANK YOU ALL SOOOOO MUCH!!!!!  We were planning on having moved aboard full time already, looks as tho it may be a few more months. Hopefully before next winter. Seems we still have many other issues they just keep popping up. This is our first RV and we have much to learn. At this rate we'll gain experience quickly and hopefully be able to contribute help to others on this site. Heck without this site I'd probably still be looking for the fuse box Hm? . YES this Does answer our question on the gas and then some. FANTASTIC. What a huge relief!!! Many Thanks To All Again!!!

[Rickf1985]

You FOUND the fuse box!!!!!!!!!!!!!!!!!!!! That puts you miles ahead of most of us i?? . You will find that we are  a twisted bunch once you get to know us. You will also find that the "issues" will never stop popping up. You just learn better how to deal with them as they do. Electrical issues are the biggest complaint next to leaks on these things so bone up on your DC automotive electrical knowledge. That can help you down the road.

[M & J]

So now you're calling us twisted.... Ok. 

[DaveVA78Chieftain]

Twisted Wizards   

[Rickf1985]

So now you're calling us twisted.... Ok. 

YOU Sir, are so twisted you are a knot.

[Schmitti]

The motors have to run with unleaded and ethanol - here in Germany, there is nothing else. Leaded petrol for ages no longer. Ethanol is blended in various%.

ROZ 91 (octane) = 10%
ROZ 95/98/100/102 (octane) = 5%

If that should not be the case in the US, may I now prepare that as "work" to come in the classic cars on you. ALL fuel lines and the pump must withstand the ethanol - old rubber pipes and membranes may not necessarily represent a permanent and devoured by the ethanol.

Thomas

[Alexarae]

Twisted  Excellent !!! also good to know. We'll fit in quite well here then  :)rotflmao Thanks !!!

Fair winds and following seas to all

[kansascat]

Sooo if i am following correctly i can stop worrying about my 79 model 454 getting burnt valve seats from running on unleaded? And i am hoping that since i rebuilt the carb with a new kit and a new fuel pump that they have rubber and plastic that is now ok with ethanol fuels? Safe to think this or should i keep worrying.  LOL

[Rickf1985]

It is safe to stop worrying. Even if you had the older heads then it would not be cost effective to pull the heads to have all the seats changed until you had a problem and then you do something about it. I know of 1960's vehicles that have over 300,000 miles on them with the original leaded gas heads on them and they are running fine. And these are NOT garage queens, they are driven hard.