Lead substitute for Daytona

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Paul
Posts: 46
Joined: Mon Sep 09, 2002 9:49 pm

Lead substitute for Daytona

Post by Paul »

I recently purchased a low milage 1971 Daytona. Should I be using a lead susitute in the gas? If so, is one lead subsitute better than the next? Great web site!!! Thanks, Paul[/img][/quote]
tyang

Post by tyang »

Hi Paul,

I'm glad you like the site!

I don't think you need to worry about lead substitute. IMHO, most of the fears of valve seat recession when leaded gas was phased out was largely overrated.

Are you planning on racing the car? Regular use shouldn't have any problems using unleaded provided it has enough octane.

Tom
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Yale
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Joined: Mon Sep 02, 2002 4:56 pm
Location: New York City

Post by Yale »

According to a friend of mine, Jaime Kitman, who writes for quite a few auto publications and owns 14 cars(!?) the whole lead substitute issue is a crock. He wrote an article about lead additives for The Nation magazine after seeing all the hoopla in the recent UK motor press about -- no lead ready -- hardened valves. After getting sick and tired of adding lead to his fleet of older, mostly British cars, he stopped and then realized, 12 years later, that no untoward things had happened to their motors.

In his piece, which the Nation liked so much it gave it a full issue, his extensive research showed that not only was lead not necessary for the long life and health of an engine, not only was it harmful to people, but lead was destructive to our cars as well.

GM owned the patented process for adding lead to gasoline. And along with Dupont, made sure that lead additives were the prefered method for raisong octaine, (which it DID raise octaine, but was not the only possible choice and among the least safe).

Yale
Paul
Posts: 46
Joined: Mon Sep 09, 2002 9:49 pm

Post by Paul »

[quote="tyang"]Hi Paul,

I'm glad you like the site!

I don't think you need to worry about lead substitute. IMHO, most of the fears of valve seat recession when leaded gas was phased out was largely overrated.

Are you planning on racing the car? Regular use shouldn't have any problems using unleaded provided it has enough octane.

Tom[/quote]
Paul
Posts: 46
Joined: Mon Sep 09, 2002 9:49 pm

Octane for 1971 Daytona

Post by Paul »

What is the lowest octane that this car should accept? Thanks, Paul
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Jim
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Location: Pasadena, CA

Post by Jim »

Hi,
If my memory serves me correctly, I recall that new, unhardened valve guides only needed the lead exposure from the first tank of gas, and would be thereafter lubricated for life. That is, no lead needed after the initial tank of gas. Of course, nowadays, new guides don't need the lead, and older cars would have originally seen leaded gas, and thus operate well thereafter on unleaded. The only issue is running a decent octane, which is readily available, at least in the USA.
tyang

Post by tyang »

Hi Paul,

Considering your car is high a performance engine, and has relatively high compression, I'd run the highest octane I could find in your area. 92, 93 Octane or even 94 if it's available. With the advent of knock sensors in modern cars, you can take more chances, but with old fashioned ignition and pricy engine rebuilds in a Daytona, I would want the extra octane to keep away the detonation. Timing the engine correctly will also play a big role, but you want to give the ignition the best chance to fire correctly with the best gas around.

Tom
Paul
Posts: 46
Joined: Mon Sep 09, 2002 9:49 pm

Octane busters

Post by Paul »

Are octane boosters worth while if I can not find a high enough octane to run this car.
Thanks,
Paul
simonc
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Location: St Albans, UK
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Post by simonc »

I guess it depends where you are. In the UK I use an additive called TetraBoost in my 1977 400. I run it on Shell Optimax which is 97 octane and boost it to 99+ with the TetraBoost, which is the actual lead additive that used to be in petrol. Not sure it is available elsewhere though.
kare
Posts: 547
Joined: Sun Sep 22, 2002 11:34 am
Location: Helsinki, Finland, Europe

Post by kare »

[quote="Yale"]
>After getting sick and tired of adding lead to his fleet of older, mostly
>British cars, he stopped and then realized, 12 years later, that no
>untoward things had happened to their motors.

In many cases it can be very hard to determine, whether the valve seats and/or guides tolerate unleaded fuel (maybe your heads were rebuilt years ago with steel inserts, maybe the fellow with a similar car who said it's OK had a rebuilt engine...?) It can be even harder to find out whether your "green" fuel includes lead substituting agents. The distributor doesn't always know, the fuel company doesn't usually care. Maybe the guy who said his engine runs well with unleaded was using substituted gas all the time without even knowing it?

As far as I know I live in the only country in the world (Finland), where lead as a fuel additive has been TOTALLY banned for more than 12 years. I've seen and heard many sad stories of people who were not aware of this. About 2000 easy miles this summer were enough to roast the valves on my sister's 1971 Fiat. (I told her, she wasn't listening...)

Want to experiment with a Daytona? Daytona MAY have been built to meet the 1971 US regulations for low lead content but does it run properly in long term with no lead or lead subsitute at all?
tyang

Post by tyang »

Hi Kare,

I'd be curoius to see if the roasted valves on that FIAT were directly related to unleaded fuel.

Tom
Chris Coios

Post by Chris Coios »

The 'roasted' valves on the FIAT could also be the result of many other factors aside from the seat material relative to the unleaded fuel. Correct cam timing and valve clearances, as well as ignition timing and cooling of the valve area, are critical to the life of the valve. Chris
kare
Posts: 547
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Location: Helsinki, Finland, Europe

Unleaded & valves

Post by kare »

[quote="tyang"]
>Hi Kare,
>I'd be curoius to see if the roasted valves on that FIAT were directly
>related to unleaded fuel.

In this case I think I'm quite safe saying yes. Clear valve recession in all exhaust valves can - AFAIK - only occur with "old school" valve/seat material combination when the protection fails.

Kare
Paul
Posts: 46
Joined: Mon Sep 09, 2002 9:49 pm

Lead substitute for Daytona

Post by Paul »

Thanks for all your advice. I thought I would report in on what I have learned from different sources. In 1971 (when my car was born) we were running on "low leaded" gas. When the lead was removed other additives were also removed. Unfortunately only lead (tertraethyl lead) got the bad rap and was the one to hit the news. But when lead went other additives that also worked inconjunction with lead no longer were in the gas. Gas today is called "dry gas" because many of the additives like lead (and the petrleum lubricants) are missing making the gas white. Gas used to be blue because of the petrulium products. Can lead do anything by itself? Most scientists and engine rebuilders think not. Lead was initially suppose to be a lubricant. It didn't work that well. But it was a great heat sink for the engine. In other words it moved the heat away from the valves, valve guides and valve seats. The bottom line. If you are not racing your car it probably doesn't matter if you use any additive. Ferrari Daytonas were built to withstand great engine stress. Most of us will not drive the cars the way they should be driven. We will not build up heat differentials in the engine to make it matter (if you race, what I am saying is not for you). As far as octane boosters the same is true. When you are driving at nomal (60-100 MPH) speeds your octane requirement drops down to about 30. Only during extreme fast starts and stressful hill climbs would you maybe need more than 91 octane. If you feel you need to put something in your engine (like me) Marvals Mistery Oil (sp) (MMO) may be the thing. It's cheap and and it has been around forever. It was used on the flat head engines in the 1930's because the great gas they had back then poorly penetrated the valve guides. MMO was placed in a canaster on top of these engines and gravity fed the cylinder head. In that way the valves were lubricated. If you have an original vintage engine with original valves and valve guides which may (unlikely) heat up simply lubricating the engine with MMO might help. Bottom line...if you are a driver like me...you probably don't have to do anything.
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