My 394cid calls for premium fuel so the question is this. Premium fuel in the 60's is equall to what fuel today (83, 87, 93, etc)?

Not sure if the standards for fuel are still the same or not, everything else seems to change so...

 

in 1966 the octane rating on fuel was 107 octane. Now the highest is 93, has something to do with the maximum yeild refining process and taking the lead outta fuel. The funny thing is if you look at the octane rating on E-85 (corn based alcohol) you can see its also 107. But.....here's where we run into the problem with special rubber seals on our fuel related parts, it gets really tough on an old car due to the fuel pump diaphram and rubber fuel lines. Hope this helps answer some of your questions about our old nemesis:lack of octane and pinging. Oldsdroptop

 

Didn't the removal of the lead from gasoline also result in damage to the valve seats in the older engines? Or is that just an urban legend so manufacturers could sell the special "additive"?

 

I always heard you had to use lead additives . Unless you have the heads updated.

 

The 394 will run fine on the 93 octane fuel. The use of lead additives always causes a lot of discussion both pro and con . If you are worried about it then use a name brand additive if not don't. If you need to do a valve job anyway then have hardened seats installed then you won't have to worry about it. Several people here and on other sites have put thousands of miles on older engines with no ill effects.

 

hmm in pa you must have a little different set up or somthing.I have never heard of 83 octain gas.In Ny your neighbor to the north we have 87 89 and 93 then you have the e85 though there is a certain amount of corn fuel in all the gas now.I never put much thought into it but I have been running 87 in my 67's 330 seems ok though a had asked a few people about addatives like the lead one.I was told my car didn't need it.

 

I just tried a full tank of 93 octane fuel and tried to get the octane levels up the best I could via an octane booster to see how my car would perform. The engine pinged more doing this, than simply using the straight 93 octane fuel. I believe it's a timing issue - my car was probably timed with the straight fuel (before purchasing it). The octane booster was a Lucas product.

I won't be doing that again.

 

Running 93 octane here and never any drive ability problems. Lead additives are poison and not required.

 

Thanks all and being in my 30's I had no idea octain was so high in the OLDS days (sorry weak attempt for a joke).

delmontcrusier,
In PA we have the same fuel as NY, I just screwed up in initial my post.

So I always ran 87 in my 394 with no problem (one would think that would not be the case), if I use a higher octain I'll re-time the engine.

Ben

 

Lead was an additive to lubricate the upper valve train, when we found it was not good for us it was replaced with other additives that do the same function. Think about it, which vehicle has more valve train surface needing lubrication, a classic 5.7 liter or higher V8 with sixteen valves or a modern 5.0 liter or less V8 with 32 valves (that probably turns higher rpms as well). I don't sweat it at all.

 

after I moved up from cuttin lawns I got a job at sunoco, musta been around '73
we had 190 through 260 and you could custom blend the two, I believe the 260 was 104 octane, I think the lowest octane was 93 for the economy 190 my how things have changed

then there was cam 2 racing gas some of the old timers then said there was sunoco 280 but I never saw it...

 

We had Chevron white pump which if I remember correctly was 112 Octane. All of the guys used it when they went drag racing, it made a huge difference. Been out of production since the 1975 gas crunch

 

So another confusing thread... at least to me! Should I be putting lead substitute in the prettiest one?? I've been using it for a couple years, but if I don't have to, I won't! Someone told me when I got her that I should do this.

 

Todays gasoline has changed a lot from the the good ole days. I don't use lead additive and never have. Its simply not needed. At some point when lead was being phased out, Olds began using a flame induction hardening process on its valve seat. This process was to relieve recession on the valve seats which the lead helped to protect in the earlier years.

Higher octane does not relate to performance of the engine. Only the engines ability to resist detonation or knocking. The compression ratio alone is the important factor in deciding to using higher octane fuel. Higher octane fuel actually burns slower...by miliseconds. Common misconception is to use higher octane fuel and get more power. You really don't get more power. You get more detonation, or knocking.

I'm no petro-engineer believe me, but the chemical make up of gasoline has changed a lot. Companys have been altering the hydrocarbon chain at the moleculer level for years. Its synthetically altered. Think about it, we have "oxygenated" fuels, winter and summer blends in parts of the country. Some company has adds on tv about how their fuel is somehow better because it has nitrogen in it. Since when has nitrogen become flammable?

 

You can but you really don't need to.
The 1971 and newer heads have hardened valve seats and your compression ratio isn't high enough to worry about knocking and pinging.

The gas and valve seat stuff is covered here.

http://tech.classicoldsmobile.com/44.shtml

A lot of guys that do use stuff use Max Lead 2000 that I know around this area, not a lead substitute, it's real tetraethyl lead.

http://maxlead2000.com/

 

Premium leaded gas back in the day was in the 98-100 range.

Sunoco 260 was 104 out of the pump....for .37 a gallon.

Smelled GOOD.....

 

Ok - no more lead substitute!!

 

i do believe that I read somewhere recently that in 69 the 455 , 365hsp. with C heads required the premium leaded fuel of the day which was I believe they recommended at least 104 octane. My car has not had the heads done so I still consider using lead substitute.

 

While driving though the US a few years ago I saw a few Sunoco stations that had a 104Octane pump. The price on the fuel was HUGE but they were avail. As far as the E85 goes its a complete waste of time because the Octane might be higher than standard gasoline but it has 10% fewer BTU's which means less power.

 

My wife's dad owned a "real" old time Sunoco station, she worked there too.
I saw my future and present wife pumping gas one warm and sunny summer day in her tight hip-hugger bell-bottom blue jeans, tied up in a knot in the front blue pinstriped Sunoco shirt, blond hair in pigtails, and she even opened hoods and checked the oil and battery.
It was love at first site.

Sunoco had the blend-o-matic pumps and they mixed from different storage tanks to make the several different octane levels you had to select from there.

An older guy I worked with many moons ago said one tank contained the "pure octane" ??? and back in '63 he managed to get some and put it in his '56 Olds.
He said he was trying it out driving through this huge strip shopping center parking lot, pegged the speedometer and shortly after the engine blew because of that "pure octane". He wiped out because the brakes were useless and rammed the brick wall of a store, car was destroyed.

He did give me some nice Olds Fiesta spinner wheel covers he said were on it, so who knows.
I put them on my beater '55 Furd, he told me the Olds Fiesta wheel covers were the coolest thing you could ever have on your car.

 

Aaahhhh... you're such a romantic!! That's sweet! Nothing like grease under the fingernails! She is so nice! I really enjoyed talking to her.
I try to tell my daughter about the old gas stations that used to have service bays, and people used to pump the gas, pop the hood and clean the windshield... she looks at me like I'm crazy!!

 

My Oldsmobile can't run anything but Hydrazine. It will ping too bad with anything less.

 

That is the funniest thing I have heard in years!!! "PURE OCTANE" LOL. Octane is just a rating of resistance to detonation not an actual substance. There are many different chemicals added to fuel that give it, its octane rating.

As far as mixing the gas all modern day pumps work this way as well. Most stations don't actually have tanks holding 3 seperate grades of fuel. They have the low grade (87octane) and the premium (93-94 octane). If you select the middle grade (89-91) the pumps just automatically mix the correct proportions of the low & premium grades.

 

And I think you've probably gone over the heads of 3/4 of the folks on here...

Nasty stuff. I was glad when we quit using it in boiler water treatment.

My experience is that 394's don't particularly like 93 or less octane fuel. Maybe because all mine have been Starfire engines.

"Pure octane" blowing an engine: High-octane leaded fuel will wreck a low-compression air-cooled engine in short order because it doesn't readily burn off the lead deposits, but a high-compression air or water-cooled engine shouldn't see any ill effects except possible lead fouling of the plugs, and you can experiment with heat range and eliminate that. Airplanes use super-high lead content fuel even now (compared to currently available pump gas anyway) and they don't have catastrophic lead-related failures.

 

That is interesting. You learn something new everyday. I wonder why the local Sam's Club only has Regular and Premium. I guess they don't have the pumps that mix the Mid-grade.

I've heard of old timers mixing aviation fuel with Regular gasoline to run in their hot rods.

FWIW:

http://en.wikipedia.org/wiki/Hydrazine

 

I had to revive this thread since gas keeps changing. I have a few places that sell non ethanol fuel and I like it much better. The odd thing is 91 is the top grade at the one place and they do sell 87 non ethanol but it is only ten or twenty cents cheaper than the 91. The 87 with 10% ethanol is the cheapest but it is garbage fuel. I have been spoiling the 67 with the non ethanol and it likes it. I think 04 was the year that they made the mandatory 10% claiming it helped farmers and was said to make fuel cheaper. I have to say I noticed a decrease in fuel economy almost immediately with that ethanol. I also miss the days I could fill my car for 20bux now lucky if it is even close to half a tank.

 

[QUOTE=rocketraider;114917]And I think you've probably gone over the heads of 3/4 of the folks on here...

Hydrazine = rocket fuel. Oldsmobile = Rocket. Sophomoric humor but kinda funny nonetheless.