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Just read a disturbing article in the club mag about LRP.
Now that it is pretty well impossible to get leaded petrol in AUS,
what do we do about valve recession.
I filled up with LRP for the first time on the weekend ,after reading this article I'm not game to drive the car with that ****e in the can.
What's the situatition with LRP in the States

BTW for the Brisbane local , I think I have a infestation of Fire Ants.

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I'm not sure what LRP is, but here we only have unleaded gasoline, except for some racing gases. Some low compression, low stress engines can get away with running it, but I add lead substitute to the gas in my 10:1 289. cheap insurance. The effect is gradual, so if you get to a point where you need a valve job, you can add hardened valve seats so that you can run unleaded. Not knowing what LRP is, I can only hope that I provided some worthwhile information.
Jim

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We haven't had leaded gas in Canada for 25 years. It is not a problem unless you have a high stressed engine that sees a lot of heavy use.

Paul
1965 Mustang 2+2
1989 Mustang GT Convertible
MCA #27261
MCA certified judge for 65's and late models
 

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You could write volumes on it here. Unleaded gas has been available since mid July of 1974 when basically all new for 1975 cars came out with cats. The last time I remember seeing leaded gas sold in NJ was about 81 or 82 when it was banned alltogether.

To me it seemed everyone was running around screaming about valve recession due to the lack of lead but everyone paid little attention to the lack of octane in the leaded gas! Before the lack of lead does any damage, the lack of octane did it's damage WAY sooner! I've seen several cars at the dealer where I worked in the mid seventies with holes in the pistons from the lack of octane.

Over the years I read many articles on the subject, mostly out of curiousity, on unleades gas written by oil companies, U.S. military, taxi fleets ect.. is a lot of negative hype. The U.S Military found no ill effects of un-leaded, taxi companies found prolonged engine life with less cylinder wall wear.And Amoco gas has sold unleaded gas since the mid fifties over here, a engineer for them once wrote that they never had any customers complaints about engine problems do to the lack of lead. One of my old neighbors use to use it specifically in his cars in the fifties and swore by the Amoco unleaded gas. He told me that he would get an easy 150,000 + miles out of his cars without any engine or valve problems or replcing exhaust systems!

Leaded gas came out over here after WW II, all the gas before that was unleaded. I read that when leaded gas came out, there were valve wear problems! They had to change valve seat angles for the leaded gas.

I think the whole thing is blown way out of proportion. Sure the lack of lead will accelerate wear, but it's not usually a problem on light duty vehicles, only ones like trucks that run under heavy load really should have concerns. And the fix is easy, install hardened exhaust valve seats.some big advantages with un-leaded fuel is way less engine wear, cleaner oil, longer lasting sparkplugs and exhaust systems not to mention cleaner air for our kids.

Me, I'm all for the un-leaded gas!

Tom
You can do anything you want to......ONCE!
aka "my 66 coupe"
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LRP is lead replacement petrol. Tim, British Practical Classics magazine has published an article a few years ago about tests that British Historic Vehicle Federation (can't remember correct name) made. Their test, done by MIRA, revealed severe valve seat recession with unleaded and a few (6, I think) lead replacement products that were able to fight valve recession. Some products were useless. Very disturbing was that no gas company wanted to test their LRP claiming that they were perfectly happy with their own research. Now there is a British company that is selling lead, problem is that they have started recently and they don't export yet.

I have noticed that some people say that you can use unleaded, but no facts are so far shown about valve seat recession. One guy here in Finland said that "Sure you can use, my engine doesn't ping at all with unleaded" and when I asked "what about valve seat recession?" - "What is valve seat recession" was the reply.

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I forgot to mention, the only reason lead was put into gas, was to turn cheap easy to make low octane gas into cheap easy to make high octane gas. This was found out by Dr. Kettering who was an engineer for G.M. I understand he found this out for the war effort of WW II.

Tom
You can do anything you want to......ONCE!
aka "my 66 coupe"
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Hale Boppe comet shot off my roof. See you can use 100 iso at night with no flash!
 

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Since the gasoline used to have lead(methyl lead?) in it I would assume that it was heavier so it would then be denser in droplet form in the combustion chamber. Going to unleaded gas which I assume is a bit lighter fuel may then require recalibrating the carb some. Not recalibrating would make the motor run lean and perhaps too lean and that would cause the engine to wear out faster for sure. Maybe thats where most of the problems have come from. Another possibility is that unleaded gas might need better valves and valve guides. My heads always have stainless valves and phosphor bronze seats installed.

My new iron heads have plasma flame hardened seats but my old stockers didn't have any hardening. They lasted for 6 years on unleaded 93 octane(10:1 motor) with 25,000 highway miles and another 2 years of race track flogging. When I pulled those recently the seats were still fine.


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