lead additive

[Duke W.]

Re: lead additive

From my previous post in this thread:

"Then there is the "aviation method", which yields numbers similar to MON."

From a previous post in this thread by Michael Ward:

"See Duke's post above."

[Stewart A.]

Re: lead additive

So Duke when you guys state your using Av gas 100+ your talking figures close to Mon ? Does that mean some guys are running 105 plus (Ron). Putting AV gas in a car is a real pain in the butt if you do some kays (miles for you guys) I suppose if it was available at your local gas station that would be cool. But buying it in drum Sonoco and dispensing it does my head in. What I do notice Sunoco doesn't rate there product with a Ron or Mon. So I imagine it's in mon being U.S. The 100 oct doesn't refer to R+M. But the FR 99 refers to R+M 102 oct. The rest refer to compression Ratio for what is suitable for their fuel. Probably a better method Stewy

[Joe L.]

Re: lead additive

So Duke when you guys state your using Av gas 100+ your talking figures close to Mon ? Does that mean some guys are running 105 plus (Ron). Putting AV gas in a car is a real pain in the butt if you do some kays (miles for you guys) I suppose if it was available at your local gas station that would be cool. But buying it in drum Sonoco and dispensing it does my head in. What I do notice Sunoco doesn't rate there product with a Ron or Mon. So I imagine it's in mon being U.S. The 100 oct doesn't refer to R+M. But the FR 99 refers to R+M 102 oct. The rest refer to compression Ratio for what is suitable for their fuel. Probably a better method Stewy

Stewy------
:
I'll say something I've said a "million" times before:

Run the engine with pump premium gasoline. If one experiences no significant "pinging", one does not need any higher octane fuel, including avgas. PERIOD.

As far as some folks feeling that their car "runs better" on avgas even though it does not significantly "ping" on pump premium, all I'll say about that is I consider it a "non-quantitative, highly subjective assessment which is contra-indicated by science and engineering".

However, if it makes folks feel better to use avgas when pump premium will work just fine and if it makes them THINK that their engine runs better, I suppose that's a good reason to do it. People do the same for all sorts of other things all the time. For example, they drink bottled water when most tap water is just as good or, even, better. But, they "just know" that bottled water is better for them.

[Stewart A.]

Re: lead additive

Joe I can never understand why people use AV gas when they can use pump gas. Maybe they like paying extra for it and then there is the big Johnson Rod thing. My car uses AV gas (just watch the crowd go WOW) LOL. I always thought a car would run worse on really high oct if it never needed it. Stewy

[Joe L.]

Re: lead additive

My car uses AV gas (just watch the crowd go WOW)

Stewy------


I've always believed this is a BIG part of the "phenomenon".

[Stewart A.]

Re: lead additive

I must admit I would use it just to smell the stuff I really love the smell of racing fuel. It's better than good weed !!!! LOL

[Stuart F.]

Re: lead additive

Sorry for the late post Stu my Pop just past away last week and I hit the bottle last night in a last remembrance for my old mate. I will miss him severely and not sure when this hurt will go away ! But I'm trying to think of the positive side of his life at the moment.
When I rebuilt the junker motor in my 60 that Pro Team said was a good driver (not) I had the heads machined with basic springs and lifters nothing fancy. My bro cant help himself and decided he didn't like the bowls and the runners were a bit messy so he spent god knows how many hours with the dremmel (not sure on spelling) cleaning up my now NASCAR looking heads. I sealed the valve area with a clear plastic plate and poured water into it with a burette. Did the calculations and minus the thickness of the head gasket come up with the comp figure. I was trying to get as close as possible with the most comp and still be able to run pump gas. Mobil 98 RON 8000 synergy is the only stuff that I can run without it rattling under load. I have an electronic dizzy set up and I'm not sure what the curve is so that could be a problem. It could be fully in at a low rpm ? Causing it to knock with the lower fuels. I am positive you can't run 91 or 93 with a true 11:1 and get no knocking with full advance. Stewy

Stewy;

Sorry to hear you lost your Pop. One of the hardest things to accept in life is the loss of a loved one or close friend (or in your case - both). We all go through it and it never gets any easier the older you get, take it from me. In the last two years, both of my Brothers lost their wives and now they are just that - lost. Thanks for adding to the discussion on the thread. It helps to keep our minds occupied with things about our Vettes.

Stu Fox (Stuie)

[Terry M.]

Re: lead additive

I must admit I would use it just to smell the stuff I really love the smell of racing fuel. It's better than good weed !!!! LOL

One of the thrills of going to old car shows.

[Duke W.]

Re: lead additive

So Duke when you guys state your using Av gas 100+ your talking figures close to Mon ? Does that mean some guys are running 105 plus (Ron). Putting AV gas in a car is a real pain in the butt if you do some kays (miles for you guys) I suppose if it was available at your local gas station that would be cool. But buying it in drum Sonoco and dispensing it does my head in. What I do notice Sunoco doesn't rate there product with a Ron or Mon. So I imagine it's in mon being U.S. The 100 oct doesn't refer to R+M. But the FR 99 refers to R+M 102 oct. The rest refer to compression Ratio for what is suitable for their fuel. Probably a better method Stewy

If we approximate 100LL avgas as 100 MON, which is a reasonable approximation, then the RON is about 108-110 and the PON is about 104-105.

As Joe said and I've also said numerous times, most vintage Corvettes can be operated on pump premium, but in some cases the initial timing may have to be backed down a few degrees to avoid detonation, or the centrifugal map can be slowed/lengthened.

Those who blend in avgas or high octane racing gas without having run tests to determine whether the engine will run satisfactorily on unleaded premium are wasteing a lot to time and money.

Each car and driving conditions and environment are somewhat unique, so one can't make a blanket statement. It's up to each owner to test.

Blending in high octane fuel because the previous owner did or because "someone said you have to do it" is foolish.

Duke

[Robert B.]

Re: lead additive

While many of you have mentioned the potential pluses of lead additives for the engine (and others have argued against the need), no one has mentioned the major drawback, the risk to our brains, i.e. lead toxicity. Breathing in lead gasoline fumes (both burned and unburned) in not healthy for adults but especially children. Please be careful, especially in your garage about breathing in the fumes of leaded gasoline and lead additives or getting in on your skin. Enjoy our cars, but please don't put your health at risk for them.

Robert

[Stuart F.]

Re: lead additive

Robert;

I know exactly of what you speak; I have been around the stuff (leaded gas)for over 70 years, smelled the fumes, sucked it of tanks (siphoned it and had many mouthfulls), washed parts in it and my hands, etc. and now I can't remember your name. Do you suppose it contributed to my lower back Arthritis, or perhaps my hereditary heart condition? I just wish my Government would have protected me too back in the day.

Truth be known, I'm more worried about my dog getting into some anti-freeze.

Stu Fox