Fuel additives and octane

[Millrat]

So I'm about ready to put fuel in the 62 Sprite. What additives do I need and is it necessary to run ethanol free? No old fuel in it as the gas tank is new. It ran well when we drove it to the paint guy six months ago but hasn't been started since.
Thanks!
Erik

 

[dklawson]

Additives are by choice, not mandatory. There are differing opinions on the effect of ethanol.

If your car's cylinder head has not been reworked to have hardened exhaust seat inserts, you may want to consider a lead substitute. Red Line additive has a good reputation but isn't available everywhere. However, whether to use it or not is up to you based on the amount of use you anticipate. If the car will be used a lot and you plan on putting a lot of mileage on the car then the lead substitute may slow valve seat recession. If this will be a weekend car... you may not want to even bother with the additive.

Octane boosters are typically very expensive and I have yet to hear of someone who was truly happy with them. How to handle this is up to you. You can start with premium gasoline if you want. If the engine develops spark knock you can try the octane boosters... or retard the timing a bit.

On my British cars I use a lead substitute (no hardened valve seats) and I buy mid-grade gasoline.

 

[Mychael]

I always put the highest octane I can get in my old cars. Additives if the head has not been done.
Remember also that modern fuels are not long stable in your fuel tank and go'off' pretty quick. If I expect to not be using the car for some time then I always make sure I leave it with a full tank of fuel and add a bottle of octane boost before filling.
I've found but not as yet tried an additive specifically called a fuel stabilizer, it does not offer any octane boost or lubrication properties but claims to slow down the ageing of unleaded fuel in your petrol tank.

 

[Millrat]

The head is original and I know hasn't been touched since before 1981. The car is for the weekend rather than daily use. My main concern is the correct combination to keep everyhing in the engine happy. I use fuel stabilizer in all the fuel I store and it has not let me down yet.

 

[nomad]

Frank C who went by the handle of "Spritenut" and had a more experience with spridgets than probably anyone on this forum always claimed that the A series engine was not very prone to valve seat problems.
I haven't had as much experience but have not noticed the need for much valve adjustment as one would expect if the seats were giving problems.

Other areas may have different situations but I have never used gasoline stabilizers and have often started and ran equipment with gas that was several years old. If the filler smelled of varnish rather than gas it may burn a little black but has always ran till I could add a little fresh. Most of the stuff on the market is just sales pitch IMHO.

If you need extra octane and live in an area where you can get ethanol E85 or a blender pump cansider adding a little alcohol. Great octane booster and besides adding an oxegenate to cut emissions is why it is in the poor grade gas it is blended with now.

Kurt.

 

[61frogeye]

Is it true or not: Premium fuel has less ethanol in it than the lower grades? I believe I read that it had to have less to reach the higher octane level.

I run premium and a little lead additive and my stock 948 runs great on it.

 

[SilentUnicorn]

This is confusing. If adding ethanol raises octane, why do vehicles get lower gas mileage with it?


m

 

[daveu]

I don't know what it's like in the States, but I did an online search and found several companies in my area that don't put ethanol in their fuel.

 

[JPSmit]

Is it true or not: Premium fuel has less ethanol in it than the lower grades? I believe I read that it had to have less to reach the higher octane level.

I run premium and a little lead additive and my stock 948 runs great on it.

It depends. And oil companies and governments are not clear. So, IIRC correctly (for example) I read last summer on one website that Premium Gas has no ethanol but then I read elsewhere that in New York State, all gas has Ethanol. Likewise here, I run on Shell Vpower premium because it says no ethanol on the machine. My local discount gas station (where I fill up the Mazda) makes no such claim.

BTW, Vintage Truck Magazine did a series of articles on Ethanol last year and noted that it is Hygroscopic - it attracts water. They are suggesting wintering cars with empty tanks as hygroscopic will rust the tank. I haven't done that, in part because of using ethanol free gas - it doesn't seem to me (unscientific) to deteriorate as quickly either.

 

[JPSmit]

BTW, relative to this - do additives deteriorate? I have a number of bottles of fuel additive but I don't know if I can use it - it is about 5 years old.

 

[PAUL161]

Conoco station by me advertises NO Ethanol! Their prices are always 14 to 16 cents a gallon more than anyone else. I only use it in the MGs.

 

[Millrat]

Is it true or not: Premium fuel has less ethanol in it than the lower grades? I believe I read that it had to have less to reach the higher octane level.

I run premium and a little lead additive and my stock 948 runs great on it.

Pretty much all mainline service stations have 10% ethanol in everything here in Oregon. You can get it without ethanol at the local airport and some card locks. Premium and a little lead additive sounds like the way to go.

 

[Bayless]

It seems pretty standard that all gasoline, regular and premium, has 10 percent ethanol unless labeled otherwise. Ethanol has a higher octane rating than gasoline but lower BTU. Higher octane does not equate directly to more power. It just allows for higher compression and more advanced spark before detonation occurs. The lower BTU of ethanol means lower energy. That is why it reduces mileage.

 

[nomad]

This is confusing. If adding ethanol raises octane, why do vehicles get lower gas mileage with it?



m

It seems pretty standard that all gasoline, regular and premium, has 10 percent ethanol unless labeled otherwise. Ethanol has a higher octane rating than gasoline but lower BTU. Higher octane does not equate directly to more power. It just allows for higher compression and more advanced spark before detonation occurs. The lower BTU of ethanol means lower energy. That is why it reduces mileage.

It seems pretty standard that all gasoline, regular and premium, has 10 percent ethanol unless labeled otherwise. Ethanol has a higher octane rating than gasoline but lower BTU. Higher octane does not equate directly to more power. It just allows for higher compression and more advanced spark before detonation occurs. The lower BTU of ethanol means lower energy. That is why it reduces mileage.

Yep, chemistry.
There is less energy in a gallon of alcohol than in gasoline.
I disagree with draining the tank and store cars with the tank clear full. Less space for condensation of water from the air in the tank. Being hygroscopic isn't necessarily bad because it will get rid of the water in the tank. Gas tanks used to rust out at the bottom where the condensed water collected. Also no need to worry about gas line freeze up in vehicles you drive in the winter.

Kurt.

 

[Westfield_XI]

I am an avid boater and ethanol blended fuel has been an utter disaster! In a marine environment it absorbs water which then damages fuel injectors and rusts system components. The water does not stay in suspension for very long and forms large masses in the tanks which get shaken up and mixed with the good fuel. t also breaks down much much faster resulting in gummed up injectors and carb jets. This is also a problem for small power equipment too. There have been any number of Mfg. bulletins regarding correct storage and even class action lawsuits, Google it. My boat uses a carb'd Chevy type engine and I have not had any damage, yet..... I also run a large canister water separator that I drain before I use the boat after a months storage. I have 4 tanks holding 100 gallons of fuel so it is not so easy to keep them full. Well it's easy, just expensive....

The only good I have heard is that if you run super high boost on a supercharger motor, E85 really helps prevent detonation. But if you can afford a motor like that who cares about the lower BTU' s and poor economy.

I too have several bottles of Sta Bil that are at least 10 years old and would like to know if they are any good. I found them while cleaning out boxes of old motorcycle stuff a few months ago.

 

[SilentUnicorn]

ok. lets see here- we spend more for less true gas, get worse mileage, and our equipment suffers.
Whose idea was this?


m

 

[reddsprite]

Having spent considerable time in motorsports and traveling throughout the western United States I found that gasoline formula(s)and mixtures very greatly with altitudes and federal regulations. Unleaded fuels use a combination of alcohol and benzene in their specific mixtures changing from summer to winter.
In fact in northern Nevada I noticed that unleaded regular for my tow rig was advertised at stations as 85 octane. I use a 1275 engine in my Sprite and when I rebuilt it I installed inconel inserts in the head when I rebuilt it three years ago.

I have found that once I found the right fuel curve and ignition settings most of my problems seemed to go away. I have run everything from 115 octane race gas to 92 octane unleaded pump gas and have had very little problems with detonation or run-on after engine is shut down. The real downside to the unleaded fuels is their propensity to absorb moisture as I only drive my Sprite in the good weather months. I am of the belief that the ethanol was originally used as a component of fuels to protect the platinum in catalytic converters in the late model cars-this is covered in several research studies that are in print and some are easily located at the fuel companies websites. I tune with a set of vacuum gauges and a quality advance dial timing light and my LBC seems to like the tuneup-I use a 92 unleaded and have not encountered any problems as Ihave the car on jackstands and go out and run the car bi-weekly in the shop in the harsh winter months where I live.

 

[Westfield_XI]

ok. lets see here- we spend more for less true gas, get worse mileage, and our equipment suffers.
Whose idea was this?


m

As I understand it, it was Republican Representatives and Senators from the farm states who pushed through the mandate.

 

[JPSmit]

ok. lets see here- we spend more for less true gas, get worse mileage, and our equipment suffers.
Whose idea was this?


m

As I understand it, it was Republican Representatives and Senators from the farm states who pushed through the mandate.

Don't think I am crossing the political line here (feel free to pull it if I am Boss)

but, I always understood the Iowa Caucus' figured prominantly.
Iowa Caucus & Ethanol industry

though interestingly this showed up too in googling it:
Ethanol less of an issue

 

[JPSmit]

I too have several bottles of Sta Bil that are at least 10 years old and would like to know if they are any good. I found them while cleaning out boxes of old motorcycle stuff a few months ago.

did a bit of research and found a slightly ambivalent response.

Magic Plus says: "MAGIC PLUS FUEL ADDITIVE has a very long shelf life. However, the recommended product shelf life of MAGIC PLUS FUEL ADDITIVE is three years from the date of manufacture, as indicated in the packaging. However, our test results have shown that the additive works even beyond this period. However, care should be taken to store the package under normal room temperature and a dry place, away from sources of heat."

STP says: "The storage life of STP® products is guaranteed for a minimum of two years. However, although our testing guarantees a minimum of two years' shelf life, our experience has indicated that if our products are stored properly, they can remain stable and retain their effectiveness for an indefinite period of time."

seems like it goes on forever(ish) but the companies don't want to say so.