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The unleaded gas topic...

Dave_H

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Sorry to post so much. I feel like I'm having to catch up on 26 years of lost time!! What is the deal with today's unleaded gas in older cars? What kind of damage does it do to the engine and what are some options to combat it? Thanks.
 
I think that unleaded gas is of no concern. It will do no damage. Nothing else is needed. There are others who feel differently. Anyone who stands to profit from various engine modifications or additives will also tell you differently.
D
 
This topic has come up often. Does anyone else remember the Amoco gas back in the sixties that they advertised as being lead-free? I seem to remember them saying it was the only white gas, or something like that. They said it was better for your engine because it burned cleaner, or some such statement.
 
When I get a Triumph I'm not going to bother with additives or probably even premium gas. It's just to expensive. A buddy of mine uses medium (89 rating, I think?) in his TR6 without additives and without a engine job and has never had a problem.
 
If you search the internet, you'll find a lot of interesting information regarding this subject. The general concensus is that running unleaded gasoline in a older unmodified engine designed for leaded gas will probably not increase wear significantly under normal conditions. The biggest concern is recession of the valve seats, but most everyone agrees that the increased recession due to unleaded gas will be minimal.

Kurtis
 
When you get a Triumph, you should run the lowest octane fuel that doesn't cause problems, such as pinging under load or running on (dieseling) when you shut it off. For my GT6 with minimal modifications, that means premium fuel. The good news is that it only holds 10 gallons!
 
Kurtis has a very good answer. There really is not much more wear in an older motor that just runs unleaded over a motor that runs lead additives. In my experiance I have found that additives do not decrease wear or valve recession in older cars. I have pulled down older engines owned by people from both sides of the arguement and have never noticed much difference between engines with additives and those without. The only real thing I can think of that makes a difference in an engines wear is making sure you have clean oil, and giving the engine a decent warm up period. A few years ago I read an article in "This Old Truck" which covered this topic, through a little research the author had managed to find that the average car that ran white gas in the 20s and 30s actually tended to last longer than those than ran leaded fuel, and that leaded gas was originally just a selling gimick to increase sales.
 
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A few years ago I read an article in "This Old Truck" which covered this topic, through a little research the author had managed to find that the average car that ran white gas in the 20s and 30s actually tended to last longer than those than ran leaded fuel, and that leaded gas was originally just a selling gimick to increase sales.

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Thanks for that, Walter. I was beginning to think that I had just dreamed what I said earlier about Amoco!

Mickey
 
I'd worry about other things first. Seat recession may be an issue if you do a lot (and I mean a LOT) of highway cruising. Just keep a feeler on your valve lash and if you find the gaps closing up, suspect recession. For piece of mind, you can add some No-Lead additive every other tankful or so.

Rick O.
 
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...I feel like I'm having to catch up on 26 years of lost time!!

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M*A*S*H got cancelled, Disco's dead, forget about 8-Track.

Glad to see the prevailing wisdom is to not fret to much about the unleaded thing. I think hardened seats, etc are worthwhile if the head is being rebuilt anyway, but not warranted on their own.
 
Back in the old days a valve job was routine maintenence if you drove much. Most likely, any one who has not converted to steel seats will have to some day.But why worry???? valve resession doesnt ruin the head(unless very severe). So just drive and enjoy, if a problem comes up later(a good size if)address it at that time.As for additives, you might get more from lottery tickets in the long run.
MD(mad dog)
 
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